This document discusses human growth and development from conception through adulthood. It defines growth as an increase in body size and weight, while development refers to the acquisition of skills and behaviors. The stages of development include prenatal (embryonic and fetal), infancy, childhood, adolescence, and adulthood. Prenatal development begins with fertilization and progresses through embryogenesis and fetal stages. After birth, development occurs through infancy, childhood, adolescence, and into adulthood. Nutrition, emotional support, and learning experiences influence growth and development at every stage of life.
The document summarizes prenatal development from conception through the three trimesters of pregnancy. It describes the key developmental milestones that occur each month in the first trimester such as the formation of the embryo, organs, and early movements. In the second trimester, the developing human is called a fetus and development continues with skin structures, hair growth, eye opening, and increased movement. In the third trimester, organ development is largely complete and the fetus gains weight and prepares for birth.
This document outlines the key principles and stages of human growth and development from conception through adulthood. It notes that development is a continuous process that proceeds in an orderly sequence at different rates from head to feet and from the center outward. The stages include prenatal development from zygote to fetus, neonatal development and milestones in the first years, preschool cognitive and motor skills ages 2-6, middle childhood physical and cognitive growth ages 6-12, adolescent physical changes and growth spurt ages 10-18, and adulthood with physical peak in early years and declines in middle to late adulthood.
Puberty is a period of rapid physical maturation involving hormonal and bodily changes that occurs in early adolescence between the ages of 11-16 years. It is characterized by the development of secondary sex characteristics like breast development in females and facial hair growth in males. Puberty begins with the prepubescent stage and ends with becoming postpubescent. During puberty, hormones stimulate growth in reproductive organs and rapid growth spurts occur under the influence of pituitary and gonadal hormones. The timing of puberty can impact social and emotional development.
GROWTH AND DEVELOPMENT OF ADOLESCENT AND THEIR SPECIAL NEEDSRitu Gahlawat
Adolescence is a period of rapid physical, cognitive, social and emotional development between childhood and adulthood. Puberty involves physical changes like growth spurts and development of secondary sex characteristics due to hormonal changes. Adolescents experience biological changes, cognitive development allowing for abstract thought, formation of identity, and changes in relationships with peers and family. Their nutritional, health, and mental health needs are greater during this period of transition to adulthood.
The document summarizes physical development during childhood and adolescence. It covers development of the brain, body, motor skills, problems in early childhood, growth in middle childhood, hormonal changes and puberty in adolescence. It also discusses physical and mental health issues during these stages including nutrition, sleep needs, physical activity, depression, use and abuse of drugs, and death in adolescence.
The document outlines the stages of prenatal development from conception through birth. It describes the germinal stage where the blastocyst implants and the embryonic stage where major organs begin developing. During the fetal stage, bones form and the fetus can move. The document also discusses influences on prenatal development like maternal health, nutrition, stress, and teratogens that can negatively impact the fetus.
The document discusses the cognitive development of adolescents. It notes that adolescence is a period of growing abstract thought and intellectual interests. Cognitive abilities progress from a focus on the present during early adolescence to a greater capacity for goal-setting and consideration of morality and the future in middle and late adolescence. Jean Piaget's theory of cognitive development identifies the adolescent period as the formal operational stage, characterized by logic, abstract thought, and problem-solving skills. The prefrontal cortex continues developing during this time. While cognitive growth is normal, adolescents may engage in risky experimentation as they navigate this challenging developmental period.
Adolescence involves significant physical, cognitive, and social development. Puberty brings sexual maturation between ages 11-13 which includes growth of sexual organs and secondary sex characteristics. Brain development allows for advanced reasoning and abstract thought. Socially, adolescents develop a stronger sense of identity and morality as they establish independence from parents and bond with peers. They transition into emerging adulthood between 18-25 where they live independently while attending college or working.
The document summarizes prenatal development from conception through the three trimesters of pregnancy. It describes the key developmental milestones that occur each month in the first trimester such as the formation of the embryo, organs, and early movements. In the second trimester, the developing human is called a fetus and development continues with skin structures, hair growth, eye opening, and increased movement. In the third trimester, organ development is largely complete and the fetus gains weight and prepares for birth.
This document outlines the key principles and stages of human growth and development from conception through adulthood. It notes that development is a continuous process that proceeds in an orderly sequence at different rates from head to feet and from the center outward. The stages include prenatal development from zygote to fetus, neonatal development and milestones in the first years, preschool cognitive and motor skills ages 2-6, middle childhood physical and cognitive growth ages 6-12, adolescent physical changes and growth spurt ages 10-18, and adulthood with physical peak in early years and declines in middle to late adulthood.
Puberty is a period of rapid physical maturation involving hormonal and bodily changes that occurs in early adolescence between the ages of 11-16 years. It is characterized by the development of secondary sex characteristics like breast development in females and facial hair growth in males. Puberty begins with the prepubescent stage and ends with becoming postpubescent. During puberty, hormones stimulate growth in reproductive organs and rapid growth spurts occur under the influence of pituitary and gonadal hormones. The timing of puberty can impact social and emotional development.
GROWTH AND DEVELOPMENT OF ADOLESCENT AND THEIR SPECIAL NEEDSRitu Gahlawat
Adolescence is a period of rapid physical, cognitive, social and emotional development between childhood and adulthood. Puberty involves physical changes like growth spurts and development of secondary sex characteristics due to hormonal changes. Adolescents experience biological changes, cognitive development allowing for abstract thought, formation of identity, and changes in relationships with peers and family. Their nutritional, health, and mental health needs are greater during this period of transition to adulthood.
The document summarizes physical development during childhood and adolescence. It covers development of the brain, body, motor skills, problems in early childhood, growth in middle childhood, hormonal changes and puberty in adolescence. It also discusses physical and mental health issues during these stages including nutrition, sleep needs, physical activity, depression, use and abuse of drugs, and death in adolescence.
The document outlines the stages of prenatal development from conception through birth. It describes the germinal stage where the blastocyst implants and the embryonic stage where major organs begin developing. During the fetal stage, bones form and the fetus can move. The document also discusses influences on prenatal development like maternal health, nutrition, stress, and teratogens that can negatively impact the fetus.
The document discusses the cognitive development of adolescents. It notes that adolescence is a period of growing abstract thought and intellectual interests. Cognitive abilities progress from a focus on the present during early adolescence to a greater capacity for goal-setting and consideration of morality and the future in middle and late adolescence. Jean Piaget's theory of cognitive development identifies the adolescent period as the formal operational stage, characterized by logic, abstract thought, and problem-solving skills. The prefrontal cortex continues developing during this time. While cognitive growth is normal, adolescents may engage in risky experimentation as they navigate this challenging developmental period.
Adolescence involves significant physical, cognitive, and social development. Puberty brings sexual maturation between ages 11-13 which includes growth of sexual organs and secondary sex characteristics. Brain development allows for advanced reasoning and abstract thought. Socially, adolescents develop a stronger sense of identity and morality as they establish independence from parents and bond with peers. They transition into emerging adulthood between 18-25 where they live independently while attending college or working.
Human development is the study of growth and change throughout life. It includes physical, perceptual, cognitive, personality and social development. There are 8 stages from prenatal to late adulthood. Prenatal development begins with fertilization and progresses through the germinal, embryonic and fetal stages. During these stages, major organs and body systems develop and the risks of chromosomal abnormalities are highest. Genetics and environmental factors both influence prenatal development.
This document outlines the key stages of human development from prenatal through adulthood. It describes the stages as: prenatal, infancy (birth to 3 years), childhood (3 to 12 years with early childhood from 3 to 6 years and later childhood from 6 to 12 years), adolescence (12 to 19 years with early adolescence from 12 to 15 years and later adolescence from 15 to 19 years), and adulthood (beyond 19 years). For each stage, it lists developmental characteristics such as physical, motor, emotional, social, intellectual development.
Growth refers to increases in size and weight, while development describes qualitative changes that lead to improved functioning. There are seven principles of development: continuous development from birth to death, progression from general to specific changes, sequential changes like puberty following physical maturity, unique timing of changes in each individual, interrelated social, mental, and emotional development, interaction between heredity and environment, and interaction between maturation and learning. Development involves physical, intellectual, emotional, and social growth over one's lifetime.
Human development involves cognitive, emotional, physical, and social changes across the lifespan from infancy to old age. Physical development is rapid in infancy, with growth in height, weight, and brain size. In early childhood, physical growth slows and motor skills increase. During later childhood, the body continues to mature. Adolescence involves major biological and physical changes as children reach sexual maturity. In adulthood, physical abilities peak before gradual physical declines in old age such as thinning hair, declining immune function, and sensory losses.
A project to promote conceptual learning for all;
Dr. Amjad ali arain; University of Sind; Faculty of Education; Pakistan
Stages or periods of development and learning
The couple faced a difficult decision when the wife became pregnant with their second child. Their first child had congenital adrenal hyperplasia (CAH), which can sometimes result in atypical genital development in female newborns. There was a 1 in 8 chance the new baby would also have CAH. The couple could treat the fetus with steroids to reduce this risk, but there were concerns about the long-term effects of these drugs on the fetus. Ultimately, the couple decided against treatment, and when the baby was born it was a healthy girl without any issues.
The document discusses key aspects of human development from birth to old age. It covers major periods and domains of development, as well as influential theories of development by Freud, Erikson, Piaget, and Vygotsky. Theories seek to describe and explain how development occurs and progresses through predictable stages and domains, influenced by both maturation and social/cultural factors.
This document summarizes principles of growth and development from several perspectives. It discusses what growth and development are, outlining physical and functional changes. It also discusses maturation, noting it refers to changes that occur primarily as a function of aging. Six maturation principles are outlined related to biological basis, chronological vs maturational age, plateaus/regression, readiness for tasks, and training timing. Seven principles of development are also defined related to direction, control, learning/maturation, complexity, continuity, specificity, and individuality. Erik Erikson's eight stages of psychosocial development and various aspects of prenatal, motor, language, cognitive, and moral development are also summarized.
Adolescence: The concept adolescence and the developmental tasks; Processes involved in the adolescent stage of human development; cognitive development during adolescence; personality development during adolescence; social development during adolescence; parent-adolescent relationships, the peer group, romantic relationships.
Young adulthood brings changes in physical, cognitive, and social development. Physically, people reach peak strength and health in their 20s and 30s. Cognitively, skills are at their highest, and postformal thinking emerges. Socially, most people focus on careers, relationships, and starting families. Intimacy becomes an important task as friendships and romantic partnerships form. Parenthood involves new responsibilities and transitions as identities expand to include work and family roles.
This chapter overview discusses key topics in human development across the lifespan, including theories of development, prenatal development, infancy, childhood, adolescence, adulthood, later life, and death and dying. It provides a high-level summary of important milestones, changes, and theories related to physical, cognitive, social, and emotional development at each life stage.
Here are some responses from different levels of moral reasoning:
Pre-conventional:
- No, stealing is against the rules and Heinz could get in trouble.
Conventional:
- It's a difficult situation, but stealing is illegal so Heinz should not have done it.
Post-conventional:
- Stealing violates the druggist's rights, but letting a life be lost when the means to save it exist also seems wrong. There are good arguments on both sides of this complex situation with moral dilemmas either way.
This document discusses the principles of growth and development. It defines growth as a physical process that can be measured quantitatively through indicators like height, weight and bone size. Development refers to systematic changes in complexity of function and skills. Some key principles discussed are:
1) Development proceeds from head to toe and from the center of the body outward
2) It follows sequential stages from simple to complex abilities
3) Rates vary between individuals and different parts of the body develop at different paces
4) Maturation and learning drive development as children gain new capabilities at different stages
Vygotsky placed emphasis on social contributions to development and the connections between people and their social context. He introduced the concept of the zone of proximal development, which is the distance between what a learner can do independently and with guidance. Within the zone of proximal development, scaffolding and reciprocal teaching can help students learn. Vygotsky challenged traditional teaching methods and argued for a more collaborative social approach where the teacher and students have shared roles.
This document discusses the growth and development of adolescence across multiple domains. It begins by defining adolescence as the transition period between childhood and adulthood, characterized by rapid physical, cognitive, social, and emotional changes. It then covers the biological changes of puberty, psychosocial development, cognitive development, and theories of development. It also addresses nutrition needs, sleep, exercise, sexuality education, injury prevention, and anticipatory guidance for parents.
Physical and motor development of children and adolescentMarilou Jamero
This document discusses physical and motor development in children and adolescents. It defines physical and motor skills and identifies stages of development from infancy to adulthood. During childhood, motor skills develop from large muscle movements to smaller, more refined movements. Fine motor skills involve smaller muscle groups while gross motor skills use larger muscle groups. The document provides examples of activities to develop both fine and gross motor skills. Physical development accelerates during adolescence through growth spurts and the onset of puberty bringing sexual maturity. Overall development follows predictable patterns but individuals vary in their needs and styles at each stage.
The document outlines the main stages of human development from prenatal to old age. It discusses the key characteristics of each stage, including physical, cognitive, social, and emotional changes. The stages covered are prenatal, infancy, early childhood, middle childhood, late childhood, adolescence, early adulthood, mature adulthood, and old age. The document emphasizes that development is a continuous process that occurs in predictable patterns as people mature and gain experience.
The document discusses prenatal development from conception through birth. It covers key topics like the stages of prenatal development (zygotic, embryonic, fetal), how life begins through processes like ovulation, fertilization and conception. Genetic and chromosomal abnormalities are described as well as their causes and types. Environmental factors that can negatively impact prenatal development, called teratogens, are provided as examples like certain maternal diseases and drugs. The stages of prenatal development are characterized by cell differentiation and growth of major organs and body systems.
This document outlines a course on educational psychology that covers human development and personality. It discusses key topics like the definition and processes of human development, the five major traits of personality, and Bronfenbrenner's ecological systems theory of the contexts that influence development. The course aims to help students describe, identify, explain, and discuss concepts of human development and personality and apply that understanding to teaching careers.
This document summarizes the significant life stages from young adulthood to late adulthood. It describes young adulthood from ages 20-40 as a time of experimentation and independence. Middle adulthood from ages 40-60 involves expanding responsibilities and reassessing priorities. Late adulthood from age 60 onward includes adjusting to retirement, declining health, and reviewing one's life. Key characteristics and changes are described for each phase.
This document provides an overview of key concepts in embryology. It defines embryology as the study of prenatal development from fertilization through birth. Key stages of development discussed include the zygote, morula, blastocyst, gastrula, and fetus. Common terms used in embryology like gestation, implantation, and trimester are defined. The document also discusses abortion and its different types. The overall purpose is to introduce fundamental concepts about human development from conception through birth.
Embryology-all basic definition,Stage wise development of fetus,development o...sonal patel
Embryology-all basic definition,Stage wise development of fetus,development of Zygote stage ,development of Embrionic Stage ,development of Fetus Stage all are according week development,Amnione,chorion,Fetal layer, Umbilical Cord developmentmade By sonal Patel
Human development is the study of growth and change throughout life. It includes physical, perceptual, cognitive, personality and social development. There are 8 stages from prenatal to late adulthood. Prenatal development begins with fertilization and progresses through the germinal, embryonic and fetal stages. During these stages, major organs and body systems develop and the risks of chromosomal abnormalities are highest. Genetics and environmental factors both influence prenatal development.
This document outlines the key stages of human development from prenatal through adulthood. It describes the stages as: prenatal, infancy (birth to 3 years), childhood (3 to 12 years with early childhood from 3 to 6 years and later childhood from 6 to 12 years), adolescence (12 to 19 years with early adolescence from 12 to 15 years and later adolescence from 15 to 19 years), and adulthood (beyond 19 years). For each stage, it lists developmental characteristics such as physical, motor, emotional, social, intellectual development.
Growth refers to increases in size and weight, while development describes qualitative changes that lead to improved functioning. There are seven principles of development: continuous development from birth to death, progression from general to specific changes, sequential changes like puberty following physical maturity, unique timing of changes in each individual, interrelated social, mental, and emotional development, interaction between heredity and environment, and interaction between maturation and learning. Development involves physical, intellectual, emotional, and social growth over one's lifetime.
Human development involves cognitive, emotional, physical, and social changes across the lifespan from infancy to old age. Physical development is rapid in infancy, with growth in height, weight, and brain size. In early childhood, physical growth slows and motor skills increase. During later childhood, the body continues to mature. Adolescence involves major biological and physical changes as children reach sexual maturity. In adulthood, physical abilities peak before gradual physical declines in old age such as thinning hair, declining immune function, and sensory losses.
A project to promote conceptual learning for all;
Dr. Amjad ali arain; University of Sind; Faculty of Education; Pakistan
Stages or periods of development and learning
The couple faced a difficult decision when the wife became pregnant with their second child. Their first child had congenital adrenal hyperplasia (CAH), which can sometimes result in atypical genital development in female newborns. There was a 1 in 8 chance the new baby would also have CAH. The couple could treat the fetus with steroids to reduce this risk, but there were concerns about the long-term effects of these drugs on the fetus. Ultimately, the couple decided against treatment, and when the baby was born it was a healthy girl without any issues.
The document discusses key aspects of human development from birth to old age. It covers major periods and domains of development, as well as influential theories of development by Freud, Erikson, Piaget, and Vygotsky. Theories seek to describe and explain how development occurs and progresses through predictable stages and domains, influenced by both maturation and social/cultural factors.
This document summarizes principles of growth and development from several perspectives. It discusses what growth and development are, outlining physical and functional changes. It also discusses maturation, noting it refers to changes that occur primarily as a function of aging. Six maturation principles are outlined related to biological basis, chronological vs maturational age, plateaus/regression, readiness for tasks, and training timing. Seven principles of development are also defined related to direction, control, learning/maturation, complexity, continuity, specificity, and individuality. Erik Erikson's eight stages of psychosocial development and various aspects of prenatal, motor, language, cognitive, and moral development are also summarized.
Adolescence: The concept adolescence and the developmental tasks; Processes involved in the adolescent stage of human development; cognitive development during adolescence; personality development during adolescence; social development during adolescence; parent-adolescent relationships, the peer group, romantic relationships.
Young adulthood brings changes in physical, cognitive, and social development. Physically, people reach peak strength and health in their 20s and 30s. Cognitively, skills are at their highest, and postformal thinking emerges. Socially, most people focus on careers, relationships, and starting families. Intimacy becomes an important task as friendships and romantic partnerships form. Parenthood involves new responsibilities and transitions as identities expand to include work and family roles.
This chapter overview discusses key topics in human development across the lifespan, including theories of development, prenatal development, infancy, childhood, adolescence, adulthood, later life, and death and dying. It provides a high-level summary of important milestones, changes, and theories related to physical, cognitive, social, and emotional development at each life stage.
Here are some responses from different levels of moral reasoning:
Pre-conventional:
- No, stealing is against the rules and Heinz could get in trouble.
Conventional:
- It's a difficult situation, but stealing is illegal so Heinz should not have done it.
Post-conventional:
- Stealing violates the druggist's rights, but letting a life be lost when the means to save it exist also seems wrong. There are good arguments on both sides of this complex situation with moral dilemmas either way.
This document discusses the principles of growth and development. It defines growth as a physical process that can be measured quantitatively through indicators like height, weight and bone size. Development refers to systematic changes in complexity of function and skills. Some key principles discussed are:
1) Development proceeds from head to toe and from the center of the body outward
2) It follows sequential stages from simple to complex abilities
3) Rates vary between individuals and different parts of the body develop at different paces
4) Maturation and learning drive development as children gain new capabilities at different stages
Vygotsky placed emphasis on social contributions to development and the connections between people and their social context. He introduced the concept of the zone of proximal development, which is the distance between what a learner can do independently and with guidance. Within the zone of proximal development, scaffolding and reciprocal teaching can help students learn. Vygotsky challenged traditional teaching methods and argued for a more collaborative social approach where the teacher and students have shared roles.
This document discusses the growth and development of adolescence across multiple domains. It begins by defining adolescence as the transition period between childhood and adulthood, characterized by rapid physical, cognitive, social, and emotional changes. It then covers the biological changes of puberty, psychosocial development, cognitive development, and theories of development. It also addresses nutrition needs, sleep, exercise, sexuality education, injury prevention, and anticipatory guidance for parents.
Physical and motor development of children and adolescentMarilou Jamero
This document discusses physical and motor development in children and adolescents. It defines physical and motor skills and identifies stages of development from infancy to adulthood. During childhood, motor skills develop from large muscle movements to smaller, more refined movements. Fine motor skills involve smaller muscle groups while gross motor skills use larger muscle groups. The document provides examples of activities to develop both fine and gross motor skills. Physical development accelerates during adolescence through growth spurts and the onset of puberty bringing sexual maturity. Overall development follows predictable patterns but individuals vary in their needs and styles at each stage.
The document outlines the main stages of human development from prenatal to old age. It discusses the key characteristics of each stage, including physical, cognitive, social, and emotional changes. The stages covered are prenatal, infancy, early childhood, middle childhood, late childhood, adolescence, early adulthood, mature adulthood, and old age. The document emphasizes that development is a continuous process that occurs in predictable patterns as people mature and gain experience.
The document discusses prenatal development from conception through birth. It covers key topics like the stages of prenatal development (zygotic, embryonic, fetal), how life begins through processes like ovulation, fertilization and conception. Genetic and chromosomal abnormalities are described as well as their causes and types. Environmental factors that can negatively impact prenatal development, called teratogens, are provided as examples like certain maternal diseases and drugs. The stages of prenatal development are characterized by cell differentiation and growth of major organs and body systems.
This document outlines a course on educational psychology that covers human development and personality. It discusses key topics like the definition and processes of human development, the five major traits of personality, and Bronfenbrenner's ecological systems theory of the contexts that influence development. The course aims to help students describe, identify, explain, and discuss concepts of human development and personality and apply that understanding to teaching careers.
This document summarizes the significant life stages from young adulthood to late adulthood. It describes young adulthood from ages 20-40 as a time of experimentation and independence. Middle adulthood from ages 40-60 involves expanding responsibilities and reassessing priorities. Late adulthood from age 60 onward includes adjusting to retirement, declining health, and reviewing one's life. Key characteristics and changes are described for each phase.
This document provides an overview of key concepts in embryology. It defines embryology as the study of prenatal development from fertilization through birth. Key stages of development discussed include the zygote, morula, blastocyst, gastrula, and fetus. Common terms used in embryology like gestation, implantation, and trimester are defined. The document also discusses abortion and its different types. The overall purpose is to introduce fundamental concepts about human development from conception through birth.
Embryology-all basic definition,Stage wise development of fetus,development o...sonal patel
Embryology-all basic definition,Stage wise development of fetus,development of Zygote stage ,development of Embrionic Stage ,development of Fetus Stage all are according week development,Amnione,chorion,Fetal layer, Umbilical Cord developmentmade By sonal Patel
Embryogenesis begins with fertilization where a sperm fuses with an egg to form a zygote. The zygote undergoes rapid cell division through cleavage and develops into a blastocyst which implants in the uterus. The cells then differentiate and organize into the three primary germ layers through gastrulation. The embryo continues to grow and develop organs over the next few weeks. Around 8 weeks, external genitalia form and the embryo becomes a fetus. The fetus continues growing and developing until birth. Lactation begins during pregnancy in preparation for feeding the infant. Prolactin and oxytocin play important roles in milk production and ejection. Breast milk provides ideal nutrition for an infant's growth and development
Human beings reproduce sexually. The male reproductive cells are sperm and the female cells are eggs or ova. When a sperm fertilizes an egg, they join to form a zygote which goes through development stages of embryo and fetus in the uterus. Pregnancy lasts around 9 months until childbirth, where the baby passes through the birth canal. The placenta provides nutrients to the developing fetus through the umbilical cord until birth.
Human reproduction involves the combination of male and female reproductive cells or gametes. During puberty, physical changes like growth of body hair and changes in body shape prepare the bodies of boys and girls for reproduction. The male reproductive system produces millions of sperm cells daily in the testes, while the female system releases a mature egg once a month from the ovaries. Fertilization occurs when sperm fertilizes an egg, initiating pregnancy, which lasts about nine months until birth.
This document summarizes the male and female reproductive systems and the process of human reproduction from conception through birth. It describes the internal and external organs involved in reproduction for both sexes. It then explains fertilization, implantation, fetal development through each trimester, and concludes with a brief overview of the birth process and a newborn baby. Key stages covered include ovulation, formation of the umbilical cord and placenta, fetal movement and development of organs, and the three stages of labor.
The document summarizes the development of human reproductive organs and the process of reproduction from conception through fetal development and birth. It describes the male and female external and internal reproductive organs. It explains fertilization, implantation, formation of the placenta and umbilical cord, and the development of the embryo and fetus over time, including the appearance of limbs and organs.
This document provides an overview of the human reproductive system and process. It begins by defining the key terms and describing puberty and the changes that occur. It then details the male and female reproductive systems, including their main parts and functions. The ovarian and menstrual cycles are explained next, followed by fertilization, gestation, birth, and assisted reproduction techniques. The document concludes by covering contraception methods.
Fertilization involves the union of an egg and sperm to form a zygote. The sperm penetrates layers surrounding the egg and fuses with the egg's membrane. The sperm and egg nuclei then fuse. The egg's membrane then changes to prevent additional sperm from entering. During embryonic development, cells undergo cleavage and differentiation, forming the three primary germ layers. Fetal development occurs over nine months as organs grow and body systems develop fully. Birth occurs in three stages as the cervix dilates, the child is delivered, and the placenta is expelled.
The document summarizes prenatal development from conception through the first trimester. It describes the key stages and events, including conception and fertilization, the germinal period where the zygote implants and begins dividing, and the embryonic period where organs and structures begin to form from the three germ layers. During this time, the developing organism is most vulnerable to environmental teratogens that can disrupt development. By the end of the first trimester, the basic structures have begun to form and the fetus is growing rapidly.
This document summarizes fetal development from conception through 28 weeks of pregnancy. It describes the key stages and changes that occur each month, including formation of major organs in the first month, development of facial features at 4-8 weeks, quickening and fetal movement around 20 weeks, and increased weight and activity from 20-28 weeks. An ultrasound is typically performed at 20 weeks to check fetal growth and development.
This document provides an overview of the human reproductive system and process. It begins by describing puberty and the changes that occur for both males and females during this time. It then details the male and female reproductive systems, including the testes/ovaries and their role in producing gametes. The document explains the ovarian and menstrual cycles and how they are regulated by hormones. It describes the process of fertilization and the development of the embryo and fetus during pregnancy. It outlines the stages of labor and birth. The document also discusses assisted reproduction techniques for infertility and various contraception methods.
The reproductive system includes organs that work together for reproduction. The male and female reproductive systems have significant differences that allow for genetic material from two individuals to combine. Diseases of the reproductive system are common. The human reproductive process involves internal fertilization through sexual intercourse, where sperm fertilizes an egg inside the female's body, leading to pregnancy and birth.
This document summarizes the process of fetal development from fertilization through the fetal periods. It describes the key stages and events, including fertilization and development of the zygote, pre-embryonic and embryonic periods where the blastocyst implants and the three germ layers form. It then covers the fetal period and development of major organ systems like the cardiovascular, respiratory, renal and others. It concludes with a section on placenta development from the chorionic villi fusing with the decidua.
This document summarizes the key stages of human development from fertilization through pregnancy. It describes the processes of cleavage, morphogenesis, differentiation and growth that occur during embryogenesis. The stages of development from morula to blastocyst to embryonic disk are outlined. During the trimesters of pregnancy, the placenta forms and the embryo embeds in the uterus while organs and limbs develop. Fetal circulation and extraembryonic membranes such as the chorion, amnion and yolk sac are discussed. The document concludes with a description of parturition and birth.
An embryo is the early stage of development of a multicellular organism. It begins as a zygote formed from the union of an egg and sperm cell. The zygote divides through mitosis to become a ball of cells called a morula, then a hollow structure called a blastula. The blastula implants in the thickened uterine wall and develops a placenta and umbilical cord over 2 months to exchange gases and nutrients with the mother's blood. As it develops over 9 months, organs and limbs form and it grows in size until birth as a baby. Eating healthy during pregnancy is important for the developing lungs and brain of the embryo/fetus.
Human development begins at conception. There are three main periods of prenatal development: the germinal period lasts 2 weeks after conception and involves cell division and implantation; the embryonic period lasts from weeks 2-8 and organs begin to form; and the fetal period lasts from months 2-9 where growth and maturation continue dramatically. By the end of the fetal period, the fetus is fully developed and capable of surviving outside the womb.
Prenatal development refers to the process by which a single fertilized egg cell develops into an embryo and eventually a fetus over a period of 10 weeks. It begins with fertilization in the fallopian tubes by a sperm penetrating the egg. The zygote then divides many times over as it travels down the tube and implants in the uterus. During the first 8 weeks, most major organs and bones form as the embryo develops and the placenta, amniotic fluid and umbilical cord form to nourish the growing fetus.
1. Prenatal development involves several key stages from fertilization through birth. During the first three months, the embryo's head and brain develop rapidly while the body remains small. Eyes, ears, arms and legs begin to form.
2. In the second trimester, from 3-6 months, growth catches up with the head. Fetal heartbeats can be heard and the skeleton seen on x-rays. Babies begin kicking. By 6 months the fetus is about 30cm and 700g.
3. In the final trimester, nutrients are important for bone, blood and nerve development. By 9 months the fetus is about 45cm and 3,000g. Birth then occurs.
The respiratory system exchanges gases through a series of organs. The document describes the key parts and functions of the respiratory system. It focuses on the nose, which warms, moistens, and filters air before it reaches the lungs. It then describes the pharynx and larynx, which continue guiding air through the upper respiratory tract. The larynx contains cartilages like the thyroid and cricoid that support vocal cord function and air passage.
1. The document discusses water, electrolyte, and pH balance in the human body. It describes the different fluid compartments, electrolyte composition and functions, acid-base balance, and mechanisms that regulate water and electrolyte levels.
2. Key points include that 60% of body weight is composed of water stored in intracellular and extracellular fluid compartments. Electrolytes like sodium, potassium, and chloride are important for fluid balance, nerve function, and pH regulation. The body maintains acid-base balance through buffer systems like bicarbonate and uses organs like the lungs and kidneys to regulate pH.
3. Imbalances can occur from dehydration, diarrhea, vomiting, or other causes and
The cardiovascular system consists of the heart and blood vessels. The heart has four chambers and pumps blood through the blood vessels. It is surrounded by layers including the outer fibrous pericardium, middle myocardial muscle layer, and inner endocardial lining. Blood flows from the heart through arteries and arterioles, into capillaries where gas exchange occurs, and returns to the heart through veins and venules. Valves in the heart and vessels ensure one-way blood flow. The cardiovascular system circulates blood to supply the body with oxygen and nutrients and remove waste.
Blood is a connective tissue composed of plasma and blood cells that circulates through the body delivering oxygen, nutrients, hormones and other substances to tissues. It transports waste products away from tissues. The main cellular components of blood are red blood cells, white blood cells and platelets. Red blood cells contain hemoglobin and transport oxygen and carbon dioxide. White blood cells help defend the body against infection and disease. Platelets assist in blood clotting. Disorders can occur if there are too few or too many blood cells or if the cells are abnormal.
The document discusses endocrine glands, specifically the endocrine gland. It defines endocrine glands as groups of secretory cells surrounded by an extensive network of capillaries that facilitates the diffusion of hormones directly into the bloodstream. Some key endocrine glands discussed include the pituitary gland, thyroid gland, and hypothalamus. The pituitary gland regulates other endocrine glands and is divided into the posterior and anterior pituitary. The hypothalamus produces hormones that regulate the anterior pituitary. The thyroid gland produces thyroid hormones that increase metabolism.
The document provides information about the digestive system, including the organs and processes involved. It describes the main parts of the digestive tract from mouth to anus. It details the layers of the digestive tract walls and explains the roles of the salivary glands, teeth, tongue, and liver and pancreas in digestion. Accessory organs help break down food while the stomach, small intestine, and large intestine further digest and absorb nutrients before waste is eliminated.
The muscular system provides motor power for all body movements through skeletal, smooth, and cardiac muscles. Skeletal muscles are voluntary striated muscles attached to bones by tendons that allow movement. Smooth muscles are involuntary and non-striated, found in organs. Cardiac muscle is exclusively in the heart. Each muscle fiber contains contractile myofilaments that slide past each other during contraction. Muscle contraction is stimulated by motor neurons at neuromuscular junctions. Contraction allows movement through pulling bones via tendons attached at muscle origins and insertions.
This document discusses the different types of joints in the human body. It begins by defining a joint and classifying joints by function and structure. The three main types by function are synarthrosis (immovable), amphiarthrosis (slightly movable), and diarthrosis (freely movable). The three main types by structure are fibrous, cartilaginous, and synovial joints. It then provides details on the different types of synovial joints and examples of various joints in the body like the shoulder, elbow, hip, knee, ankle joints. It concludes with a brief description of bursae and fontanels.
The integumentary system consists of the skin and its appendages. The skin is made up of two layers - the epidermis and dermis. The epidermis is avascular and composed of stratified squamous epithelium in five layers. The dermis lies below and contains blood vessels, hair follicles, and glands. Functions of the skin include protection, regulation of temperature and moisture, synthesis of vitamin D, and sensation. Sweat glands and sebaceous glands are important appendages that aid temperature regulation and protect the skin surface.
The skeletal system consists of bones and other connective tissues that provide structure and protect internal organs. Bones are composed of both organic and inorganic materials, including collagen proteins and hydroxyapatite salts. The skeletal system includes long bones in the limbs, short and flat bones, and irregular bones like those in the spine. Bones are living tissues that contain osteoblasts, osteocytes, and osteoclasts, which form, maintain, and break down bone respectively. The skeletal system provides structure, movement, protection, mineral storage, and blood cell formation.
The female reproductive system functions to produce eggs and hormones. It includes both external genital organs like the vulva and internal organs like the uterus, fallopian tubes, and ovaries. The ovaries produce eggs and hormones, the fallopian tubes help eggs reach the uterus, and the uterus supports pregnancy and childbirth. The system goes through monthly changes in a menstrual cycle regulated by hormones, culminating in ovulation when an egg is released for possible fertilization.
The male reproductive system consists of organs that produce and transfer mature sperm. The testes produce sperm which travel through the vas deferens, seminal vesicles and prostate gland. These organs combine their secretions to form semen, which contains sperm. During sexual arousal, erectile tissue in the penis fills with blood, causing an erection to allow delivery of semen into the female reproductive tract during intercourse.
The lymphatic system transports lymph fluid and filters pathogens. It includes lymph vessels, lymph nodes, the spleen, thymus, tonsils, and bone marrow. Lymph fluid contains lymphocytes and drains excess tissue fluid, absorbed fats, and cell debris from tissues. It transports these materials through lymph vessels and lymph nodes which filter the lymph. The spleen, thymus and tonsils are lymphatic organs that help produce and store lymphocytes to fight infection. The document describes the structures and functions of the lymphatic system components in detail.
The cardiovascular system consists of the heart and blood vessels. The heart has four chambers - the right and left atria receive blood, and the right and left ventricles pump blood out. Blood flows through arteries, capillaries, and veins in a closed circuit. The heart is a muscular pump made of cardiac muscle that is located in the chest cavity. It is surrounded by membranes and tissues that protect it. Valves ensure blood flows in only one direction through the heart and vessels.
Blood is composed of plasma and blood cells suspended in it. Plasma is 55% of blood volume and contains water, proteins, electrolytes, nutrients, waste products, hormones and gases. The three main types of blood cells are red blood cells (RBCs), white blood cells (WBCs) and platelets. RBCs contain hemoglobin and transport oxygen and carbon dioxide. WBCs help fight infection. Blood has many functions including nutrient and waste transport and immune function.
The document summarizes key information about endocrine glands and their hormones. It discusses that endocrine glands are groups of secretory cells that release hormones directly into the bloodstream. The major endocrine glands include the hypothalamus, pituitary gland, thyroid gland, parathyroid gland, adrenal gland, ovaries, testes, pancreas and pineal gland. Each gland secretes specific hormones that target distant tissues, regulating processes like growth, metabolism, reproduction and homeostasis. Hormone secretion is regulated by negative feedback loops between the hypothalamus and pituitary gland.
The document discusses the senses and sensory organs. It describes the five special senses - sight, smell, taste, touch, and hearing. It explains that sensory receptors convert stimuli into nerve impulses. The main sensory receptors are mechanoreceptors, chemoreceptors, photoreceptors, and thermoreceptors. Each sense organ contains specific receptors - for example, rods and cones in the eye and hair cells in the ear. The document then provides detailed descriptions of the eye, tongue, nose, skin and ear as sensory organs.
The peripheral nervous system (PNS) connects the central nervous system to the limbs and organs. It consists of 12 pairs of cranial nerves that originate in the brain and 31 pairs of spinal nerves that branch off of the spinal cord. The cranial nerves have various sensory and motor functions, and the spinal nerves branch into plexuses that innervate different body regions. The autonomic nervous system, a division of the PNS, regulates involuntary functions and has sympathetic and parasympathetic divisions that work in opposition to activate "fight or flight" responses or rest and digest functions.
The central nervous system consists of the brain and spinal cord, which are covered by three layers of meninges. The brain is divided into the forebrain, midbrain, and hindbrain. The forebrain includes the cerebrum and diencephalon. The cerebrum is made up of four lobes that control functions like movement, sensation, thought, and memory. The diencephalon contains the thalamus and hypothalamus, which relay sensory information and control autonomic functions respectively. The midbrain relays information between the brain and spinal cord. The hindbrain contains the cerebellum, pons, and medulla, which coordinate movement, relay information, and control vital functions. The spinal
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Rasamanikya is a excellent preparation in the field of Rasashastra, it is used in various Kushtha Roga, Shwasa, Vicharchika, Bhagandara, Vatarakta, and Phiranga Roga. In this article Preparation& Comparative analytical profile for both Formulationon i.e Rasamanikya prepared by Kushmanda swarasa & Churnodhaka Shodita Haratala. The study aims to provide insights into the comparative efficacy and analytical aspects of these formulations for enhanced therapeutic outcomes.
2. Growth
The speed with which normal growth occurs in length before birth and in
length after birth is known as growth
Development
It is defined as the acquisition of knowledge, skill, attitude and behavior
from conception to child birth and up-to adulthood.
3. Differences Between Growth And Development
SN. Growth Development
1 It is indicative i.e increase in body
size, weight,etc.
It is not indicative.
2 It is quantitative process. It is qualitative progress.
3 It is physical change. It is psychological change.
4 It is external in nature. It is internal in nature.
5 It stops at certain age. It is continuous process.
6 It is physical progress. It is cognitive progress.
4. Factors Affecting Growth And Development
Good nutrition
Emotional support
Play and language training
Eight Basic Needs For Healthy Emotional Development Of A Child
Love
Security
Acceptance an individual
Self respect
Achievement
Recognition
Independence
Authority
5. Age Of Growth And Development In Children
Infancy
From birth to 2 years
A child jumps, walk and learns to talk.
A child starts learning about simple, social concepts.
The body growth is accelerated.
6. Early Childhood (2 To 6 Years)
Infancy features are strengthened.
Physical growth occurs like: expansion of muscle, speed in body action,
changes occur in respiration, blood pressure develops, etc.
Language skill is developed and learns new words.
New concept about social relationship develops.
Memory increases.
They ask question about the environment.
Emotional development starts to develop.
Socially heshe develops new friends and want social approval of his/her
action.
7. Adolescence (12-19 years)
Physical growth
Mental or intellectual development
Emotional development
Characteristics Of Emotions In Adolescence
Complexity
Development of abstract emotions
Widening of emotional feeling.
Bearing tension
Sharing of emotions
Hopes and aspirations develop about future.
Increase to compassion in them.
9. Adulthood
Begins at 20 years; middle age commencing at 40 years; old age at about
60 years.
Changes occurs in biological and psychological domains of human life
from end of adolescence until end of life.
Biological changes influence psychological and interpersonal
developmental changes.
Legal definition: they are considered responsible for their own actions
and therefore legally accountable for them.
10. Old Age Or Senescence
It is the gradual deterioration of function characteristics of most complex
life forms.
11. Embryology
Embryology is the branch of anatomy which deals with the development
of an individual before birth.
It deals with the various changes occurring during growth from egg to an
adult.
Fusion of male and female gametes initiates embryogenesis.
Developing individual before 2 months is called embryo and after 2
months is called fetus.
12. Prenatal Period
It is the time period of human development before birth of the baby.
Fertilization: fusion of ovum and spermatozoa forming zygote, occurs at 1st day.
Cleavage: split of zygote in smaller daughter cells, starts 2nd day of fertilization
Blastomere: cell which is formed after cleavage of zygote.
Morula: 12-32 blastomeres, occurs at 3rd to 4th day.
Blastocyst: 5th day
Implantation: 6th day
13. Prenatal Period
Bilaminar disc formation: 2nd week
Trilaminar disc formation(gastrulation): 3rdweek
Neurulation(formation of neural tube): 3rd – 4th week
Embryo: up-to 8th weeks, all major structures will form.
Fetus: unborn offspring 8th weeks to 40 weeks
Conceptus: embryo and fetal membranes
14. Postnatal Period
It is the time period of human development after birth.
Neonate: one month baby
Infant: one year baby
Childhood: 13th month to puberty
Adolescent: 11 years to 18 years
Adulthood: 19-21 years
Adult: 22-40 years
Middle age: 41-55 years
Old age: above 56 years
17. Fertilization
Creation of a new human being begins with fertilization, the union of a
spermatozoon and an ovum to form a single cell.
After fertilization occurs, dramatic changes begin inside a woman’s body
and in the egg.
The cells of the fertilized ovum begin dividing as the ovum travels to the
uterine cavity, where it implants in the uterine lining.
For fertilization to take place, however, a spermatozoon must first reach the
ovum.
18. Fertilization continued…
Although a single ejaculation deposits several hundred-million spermatozoa, many
are destroyed by acidic vaginal secretions. The only spermatozoa that survive are
those that enter the cervical canal, where they’re protected by cervical mucus.
The ability of spermatozoa to penetrate the cervical mucus depends on the phase
of the menstrual cycle at the time of transit.
Early in the cycle, estrogen and progesterone levels cause the mucus to thicken,
making it more difficult for spermatozoa to pass through the cervix.
During midcycle, however, when the mucus is relatively thin, spermatozoa can
pass readily through the cervix.
Later in the cycle, the cervical mucus thickens again, hindering spermatozoa
passage.
19. Fertilization continued…
Spermatozoa travel through the female reproductive tract at a rate of
several millimeters per hour by means of whiplike movements of the tail,
known as flagellar movements.
After spermatozoa pass through the cervical mucus, however, the female
reproductive system “assists” them on their journey with rhythmic
contractions of the uterus that help them penetrate the fallopian tubes.
Spermatozoa are typically viable (able to fertilize the ovum) for up to 2
days after ejaculation; however, they can survive in the reproductive tract
for up to 4 days.
20. A zygote is “born”
Before a spermatozoon can penetrate the ovum, it must disperse the
granulosa cells (outer protective cells) and penetrate the zona pellucida—
the thick, transparent layer surrounding the incompletely developed ovum.
Enzymes in the acrosome (head cap) of the spermatozoon permit this
penetration.
After penetration, the ovum completes its second meiotic division, and the
zona pellucida prevents penetration by other spermatozoa. The head of the
spermatozoon then fuses with the ovum nucleus, creating a cell nucleus
with 46 chromosomes.
The fertilized ovum is called a zygote.
21.
22. Pregnancy
Pregnancy starts with fertilization and ends with childbirth; on average, its
duration is 38 to 40 weeks.
During this period (called gestation), the zygote divides as it passes
through the fallopian tube and attaches to the uterine lining via
implantation.
A complex sequence of pre-embryonic, embryonic, and fetal development
transforms the zygote into a full-term fetus.
23. Making predictions
Because the uterus grows throughout pregnancy, uterine size serves as a
rough estimate of gestation.
The fertilization date is rarely known, so the woman’s expected delivery
date is typically calculated from the beginning of her last menses.
The tool used for calculating delivery dates is known as Nägele’s rule.
Here’s how it works: If you know the first day of the last menstrual cycle,
simply count back 3 months from that date and then add 7 days.
For example, let’s say that the first day of the last menses was April 29.
Count back 3 months, which gets you to January 29, and then add 7 days
for an approximate due date of February 5.
24. Stages Of Fetal Development
During pregnancy, the fetus undergoes three major stages of
development:
Pre-embryonic period
Embryonic period
Fetal period.
25. The pre-embryonic phase starts with ovum fertilization and lasts for 2
weeks. As the zygote passes through the fallopian tube, it undergoes a
series of mitotic divisions, or cleavage.
During the embryonic period (gestation weeks 3 through 8), the
developing zygote starts to take on a human shape and is now called an
embryo. Each germ layer—the ectoderm, mesoderm, and endoderm—
eventually forms specific tissues in the embryo.
The organ systems form during the embryonic period. During this time, the
embryo is particularly vulnerable to injury by maternal drug use, certain
maternal infections, and other factors.
26. During the fetal stage of development, which lasts from the 9th week until
birth, the maturing fetus enlarges and grows heavier.
Two unusual features appear during this stage:
The fetus’s head is disproportionately large compared with its body.
(This feature changes after birth as the infant grows.)
The fetus lacks subcutaneous fat. (Fat starts to accumulate shortly after
birth.)
27. Pre-embryonic Development
The pre-embryonic phase lasts from conception until approximately the
end of the second week of development.
Zygote formation
As the fertilized ovum advances through the fallopian tube toward the
uterus, it undergoes mitotic division, forming daughter cells, initially called
blastomeres, that each contain the same number of chromosomes as the
parent cell.
The first cell division ends about 30 hours after fertilization; subsequent
divisions occur rapidly.
28. Pre-embryonic Development continued…
The zygote, as it’s now called, develops into a small mass of cells called a
morula, which reaches the uterus at or around the 3rd day after
fertilization.
Fluid that amasses in the center of the morula forms a central cavity. The
structure is now called a blastocyst.
The blastocyst consists of a thin trophoblast layer, which includes the
blastocyst cavity, and the inner cell mass.
The trophoblast develops into fetal membranes and the placenta. The
inner cell mass later forms the embryo (late blastocyst).
29. Pre-embryonic Development continued…
During the next phase, the blastocyst stays within the zona pellucida,
unattached to the uterus.
The zona pellucida degenerates and, by the end of the 1st week after
fertilization, the blastocyst attaches to the endometrium.
The part of the blastocyst adjacent to the inner cell mass is the first part to
become attached. The trophoblast, in contact with the endometrial lining,
proliferates and invades the underlying endometrium by separating and
dissolving endometrial cells.
During the next week, the invading blastocyst sinks below the
endometrium’s surface. The penetration site seals, restoring the continuity
of the endometrial surface.
31. Embryonic Development
Each of the three germ layers—ectoderm, mesoderm, and endoderm—
forms specific tissues and organs in the developing embryo.
Ectoderm
The ectoderm, the outermost layer, develops into the:
• epidermis
• nervous system
• pituitary gland
• tooth enamel
• salivary glands
• optic lens
• lining of the lower portion of the anal canal
• hair.
32. Mesoderm
The mesoderm, the middle layer, develops into:
• connective and supporting tissue
• the blood and vascular system
• musculature
• teeth (except enamel)
• the mesothelial lining of the pericardial, pleural, and peritoneal cavities
• the kidneys and ureters
33. Endoderm
The endoderm, the innermost layer, becomes the epithelial lining of the:
• pharynx and trachea
• auditory canal
• alimentary canal
• liver
• pancreas
• bladder and urethra
• prostate.
34. Fetal Stage
Significant growth and development take place within the first 3 months
following conception, as the embryo develops into a fetus that nearly
resembles a full-term newborn.
Month 1
At the end of the first month, the embryo has a definite form.
The head, the trunk, and the tiny buds that will become the arms and legs
are discernible.
The cardiovascular system has begun to function, and the umbilical cord is
visible in its most primitive form.
35. Month 2
During the second month, the embryo— called a fetus from the ninth week—
grows to 1 (2.5 cm) in length and weighs 1⁄30 oz (1 g).
The head and facial features develop as the eyes, ears, nose, lips, tongue, and
tooth buds form. The arms and legs also take shape.
Although the gender of the fetus isn’t yet discernible, all external genitalia are
present.
Cardiovascular function is complete, and the umbilical cord has a definite form.
At the end of the second month, the fetus resembles a full-term newborn, except
for size.
36. Month 3
During the third month, the fetus grows to 3 (7.5 cm) in length and
weighs 1 oz (28 g).
Teeth and bones begin to appear, and the kidneys start to function.
The fetus opens its mouth to swallow, grasps with its fully developed
hands, and prepares for breathing by inhaling and exhaling amniotic fluid
(although its lungs aren’t functioning).
At the end of the first trimester (the 3-month periods into which
pregnancy is divided), the fetus’s gender is distinguishable.
37. Months 4 to 9
Over the remaining 6 months, fetal growth continues as internal and external
structures develop at a rapid rate.
In the third trimester, the fetus stores the fats and minerals it will need to live
outside the womb.
At birth, the average full term fetus measures 20 (51 cm) and weighs 7 to 71⁄2 lb
38. Some of the main landmarks in embryonic/fetal development
Month Length Weight Main developmental features
1 5mm 0.02g Heart is beating
Main respiratory and gastrointestinal organs appearing
Neural tube appears (from which the nervous system develops)
Limb buds apparent
2 28mm 2.7g Endocrine glands appearing
Respiratory tree in place
Vascular system laid down; Heart development complete
Skin, nails and sweat glands present in skin
Cartilage models for bones appear
Face has human profile
3 78mm 26g Blood cells produced in bone marrow
Basic brain and spinal cord structure in place
Ossification of bones begins and muscles form
Gonads appear (ovaries in females, testes in males)
4 133mm 150g Formation of hair
Eyes and ears in place
Rapid CNS development
Joints formed
9 346mm 3.2kg At birth, many systems immature but otherwise functional. Some important adaptations
to independent life required, e.g. in cardiovascular and respiratory function
39. Structural Changes In The Ovaries And Uterus
Pregnancy changes the usual development of the corpus luteum (the ovum
after ovulation, which secretes progesterone and small amounts of
estrogen) and results in development of the decidua, amniotic sac and
fluid, yolk sac, and placenta.
40. Corpus Luteum
Normal functioning of the corpus luteum requires continual stimulation by
luteinizing hormone (LH).
Progesterone produced by the corpus luteum suppresses LH release by
the pituitary gland.
If pregnancy occurs, the corpus luteum continues to produce
progesterone until the placenta takes over.
Otherwise, the corpus luteum atrophies 3 days before menstrual flow
begins.
41. Corpus Luteum
With age, the corpus luteum grows less responsive to LH. For this reason,
the mature corpus luteum degenerates unless stimulated by progressively
increasing amounts of LH.
Pregnancy stimulates the placental tissue to secrete large amounts of
human chorionic gonadotropin (HCG), which resembles LH and follicle-
stimulating hormone (FSH), also produced by the pituitary gland.
42. Human Chorionic Gonadotropin (HCG)
HCG prevents corpus luteum degeneration, stimulating the corpus
luteum to produce large amounts of estrogen and progesterone needed
to maintain the pregnancy during the first 3 months.
HCG can be detected as early as 9 days after fertilization and can provide
confirmation of pregnancy even before the first menstrual period is
missed.
The HCG level gradually increases, peaks at about 10 weeks’ gestation,
and then gradually declines.
43. Decidua
The decidua is the endometrial lining that undergoes the hormone-
induced changes of pregnancy.
Decidual cells secrete the following three substances:
the hormone prolactin, which promotes lactation
a peptide hormone, relaxin, which induces relaxation of the connective
tissue of the symphysis pubis and pelvic ligaments and promotes cervical
dilation
a potent hormone like fatty acid, prostaglandin, which mediates several
physiologic functions
44. Amniotic Sac And Fluid
The amniotic sac, enclosed within the chorion, gradually enlarges and
surrounds the embryo.
As it grows, the amniotic sac expands into the chorionic cavity, eventually
filling the cavity and fusing with the chorion by 8 weeks’ gestation.
The amniotic sac and amniotic fluid serve the fetus in two important ways—
one during gestation and the other during delivery.
During gestation, the fluid provides the fetus with a buoyant, temperature-
controlled environment.
Later during delivery, it serves as a fluid wedge that helps open the cervix
during birth.
45. Development Of The Decidua And Fetal Membranes
Specialized tissues support, protect, and nurture the embryo and fetus
throughout its development.
Among these tissues, the decidua and fetal membranes begin to develop
shortly after conception.
46. Development Of The Decidua And Fetal Membranes
During pregnancy, the endometrial lining is called the
decidua.
It provides a nesting place for the developing zygote
and has some endocrine functions.
Based primarily on its position relative to the
embryo, the decidua may be known as the decidua
basalis, which lies beneath the chorionic vesicle, the
decidua capsularis, which stretches over the vesicle,
or the decidua parietalis, which lines the rest of the
endometrial cavity.
47. Chorion and Chorionic Villi
The chorion is a membrane that forms the outer wall of the
blastocyst.
Vascular projections, called chorionic villi, arise from its periphery.
As the chorionic vesicle enlarges, villi arising from the superficial
portion of the chorion, called the chorion laeve, atrophy, leaving this
surface smooth.
48. Chorion and Chorionic Villi
Villi arising from the deeper part of the chorion, called the chorion
frondosum, proliferate, projecting into the large blood vessels within the
decidua basalis through which the maternal blood flows.
Blood vessels form within the villi as they grow and connect with blood
vessels that form in the chorion, in the body stalk, and within the body
of the embryo.
Blood begins to flow through this developing network of vessels as soon
as the embryo’s heart starts to beat.
51. Early in pregnancy, amniotic fluid comes chiefly from three sources:
fluid filtering into the amniotic sac from maternal blood as it passes
through the uterus
fluid filtering into the sac from fetal blood passing through the placenta
fluid diffusing into the amniotic sac from the fetal skin and respiratory
tract.
52. Later in pregnancy, when the fetal kidneys begin to function, the fetus
urinates into the amniotic fluid. Fetal urine then becomes the major
component of amniotic fluid.
Production of amniotic fluid from maternal and fetal sources
compensates for amniotic fluid that’s lost through the fetal GI tract.
Normally, the fetus swallows up to several hundred milliliters of amniotic
fluid each day.
The fluid is absorbed into the fetal circulation from the fetal GI tract;
some is transferred from the fetal circulation to the maternal circulation
and excreted in maternal urine.
53. Yolk Sac
The yolk sac forms next to the endoderm; a
portion of it is incorporated in the developing
embryo and forms the GI tract.
Another portion of the sac develops into primitive
germ cells, which travel to the developing gonads
and eventually form oocytes (precursors to ova) or
spermatocytes (precursors to spermatozoa), after
gender is determined at fertilization.
During early embryonic development, the yolk sac
also forms blood cells. Eventually, it atrophies and
disintegrates.
54. Placenta
The flattened, disk-shaped placenta, using the umbilical cord as its conduit,
provides nutrients to and removes wastes from the fetus from the third
month of pregnancy until birth.
The placenta is formed from the chorion, its chorionic villi, and the adjacent
decidua basalis.
55.
56. Umbilical Cord
The umbilical cord, which contains two arteries and one vein, links the
fetus to the placenta.
The umbilical arteries, which transport blood from the fetus to the
placenta, take a spiral course on the cord, divide on the placental surface,
and branch off to the chorionic villi.
The placenta is a highly vascular organ. Large veins on its surface gather
blood returning from the villi and join to form the single umbilical vein.
The umbilical vein enters the cord, returning blood to the fetus.
57. Placental Circulation
The placenta contains two highly specialized circulatory systems:
The uteroplacental circulation carries oxygenated arterial blood from the
maternal circulation to the intervillous spaces—large spaces separating
chorionic villi in the placenta. Blood enters the intervillous spaces from
uterine arteries that penetrate the basal portion of the placenta; it leaves
the intervillous spaces and flows back into the maternal circulation through
veins in the basal portion of the placenta near the arteries.
The fetoplacental circulation transports oxygen-depleted blood from the
fetus to the chorionic villi through the umbilical arteries and returns
oxygenated blood to the fetus through the umbilical vein.
58. Placenta
For the first 3 months of pregnancy, the corpus luteum is the main source of
estrogen and progesterone—steroid hormones required during pregnancy.
By the end of the third month, however, the placenta produces most of the
hormones; the corpus luteum persists but is no longer needed to maintain the
pregnancy.
Levels of estrogen and progesterone increase progressively throughout
pregnancy. Estrogen stimulates uterine development to provide a suitable
environment for the fetus.
Progesterone, synthesized by the placenta from maternal cholesterol, reduces
uterine muscle irritability and prevents spontaneous abortion of the fetus.
59. Placenta
The placenta also produces human placental lactogen (HPL), which
resembles growth hormone.
HPL stimulates maternal protein and fat metabolism to ensure a sufficient
supply of amino acids and fatty acids for the mother and fetus.
HPL also stimulates breast growth in preparation for lactation.
Throughout pregnancy, HPL levels rise progressively.
60.
61. Labor And The Postpartum Period
Childbirth is achieved through labor—the process by which uterine
contractions expel the fetus from the uterus.
When labor begins, these contractions become strong and regular.
Eventually, voluntary bearing-down efforts supplement the contractions,
resulting in delivery.
When that occurs, presentation of the fetus takes one of a variety of
forms.
62. Onset of labor
The onset of labor results from several factors:
The number of oxytocin (a pituitary hormone that stimulates uterine
contractions) receptors on uterine muscle fibers increases progressively
during pregnancy, peaking just before labor onset. This makes the uterus
more sensitive to the effects of oxytocin.
Stretching of the uterus over the course of the pregnancy initiates nerve
impulses that stimulate oxytocin secretion from the posterior pituitary
lobe
63. Initiating Start Sequence
Near term, the fetal pituitary gland secretes more adrenocorticotropic
hormone, which causes the fetal adrenal glands to secrete more cortisol.
The cortisol diffuses into the maternal circulation through the placenta,
heightens oxytocin and estrogen secretion, and reduces progesterone
secretion.
These changes intensify uterine muscle irritability and make the uterus
even more sensitive to oxytocin stimulation.
64. Decline, Diffuse, And Contract
Declining progesterone levels convert esterified arachidonic acid into a
non-esterified form.
The non-esterified arachidonic acid undergoes biosynthesis to form
prostaglandins which, in turn, diffuse into the uterine myometrium,
thereby inducing uterine contractions.
65. All Systems Go
As the cervix dilates, nerve impulses are transmitted to the central
nervous system, causing an increase in oxytocin secretion from the
pituitary gland.
Acting as a positive feedback mechanism, increased oxytocin secretion
stimulates more uterine contractions, which further dilate the cervix and
lead the pituitary to secrete more oxytocin.
Oxytocin secretions may also stimulate prostaglandin formation by the
decidua.
66. Stages Of Labor
Childbirth can be divided into three stages.
The duration of each stage varies according to the size of the uterus, the
woman’s age, and the number of previous pregnancies.
Stage 1—Efface And Dilate
The first stage of labor, in which the fetus begins its descent, is marked by
cervical effacement (thinning) and dilation.
Before labor begins, the cervix isn’t dilated; by the end of the first stage, it
has dilated fully.
The first stage of labor can last from 6 to 24 hours in primiparous women but
is commonly significantly shorter for multiparous women.
67. Cervical Effacement And Dilation
Cervical effacement and dilation are significant aspects of the first stage
of labor.
Thinning Walls
Cervical effacement is the progressive shortening of the vaginal portion
of the cervix and the thinning of its walls during labor as it’s stretched by
the fetus.
Effacement is described as a percentage, ranging from 0% (non effaced
and thick) to 100% (fully effaced and paper-thin).
68. Dilation
Cervical dilation refers to progressive enlargement of the cervical os to
allow the fetus to pass from the uterus into the vagina.
Dilation ranges from less than 1 cm to about 10 cm (full dilation).
69. Stage 2—No Turning Back
The second stage of labor begins with full cervical dilation and ends with
delivery of the fetus.
During this stage, the amniotic sac ruptures as the uterine contractions
increase in frequency and intensity. (The amniotic sac can also rupture
before the onset of labor—during the first stage—and, although rare,
sometimes ruptures after expulsion of the fetus.)
As the flexed head of the fetus enters the pelvis, the mother’s pelvic
muscles force the head to rotate anteriorly and cause the back of the head
to move under the symphysis pubis.
70. Stage 2—No Turning Back
As the uterus contracts, the flexed head of the fetus is forced deeper into the
pelvis; resistance of the pelvic floor gradually forces the head to extend. As the
head presses against the pelvic floor, vulvar tissues stretch and the anus dilates.
The head of the fetus now rotates back to its former position after passing
through the vulvovaginal orifice.
Usually, head rotation is lateral (external) as the anterior shoulder rotates
forward to pass under the pubic arch.
Delivery of the shoulders and the rest of the fetus follows.
The second stage of labor averages about 45 minutes in primiparous women; it
may be much shorter in multiparous women.
71. Stage 3
The third stage of labor starts immediately after childbirth and ends with
placenta expulsion.
After the neonate is delivered, the uterus continues to contract
intermittently and grows smaller.
The area of placental attachment also decreases. The placenta, which can’t
decrease in size, separates from the uterus, and blood seeps into the area of
placental separation.
The third stage of labor averages about 10 minutes in primiparous and
multiparous women
72. Postpartum Period
After childbirth, the reproductive tract takes about 6 weeks to revert to
its former condition during a process called involution.
The uterus quickly grows smaller, with most of its involution taking place
during the first 2 weeks after delivery.
73. Postpartum Period
Postpartum vaginal discharge (lochia) persists for several weeks after
childbirth:
Lochia rubra, a bloody discharge, occurs immediately after delivery and
lasts for 1 to 4 days postpartum.
Lochia serosa, a pinkish brown, serous discharge, occurs from 5 to 7 days
postpartum.
Lochia alba, a grayish white or colorless discharge, appears from 1 to 3
weeks postpartum.
74. Lactation
Lactation (milk synthesis and secretion by the breasts) is governed by
interactions involving four hormones:
estrogen and progesterone, produced by the ovaries and placenta
prolactin and oxytocin, produced by the pituitary gland under
hypothalamic control.
75. Nourishment During Intrauterine Growth
In the early stages, the embryo is small enough that simple diffusion is
adequate to supply the dividing cells but because embryonic growth is so
rapid, this quickly becomes unsustainable and between the third and
10th weeks of pregnancy, the placenta develops, attached firmly to the
uterine wall.
The fetus is attached to the placenta by the umbilical cord, and absorbs
oxygen and nutrients from the maternal bloodstream as well as excreting
its waste products.
76. In Vitro Fertilization
IVF, which stands for in vitro fertilization, is an assisted reproductive
technology. In vitro, which in Latin translates to “in glass,” refers to a
procedure that takes place outside of the body.
There are many different indications for IVF. For example, a woman may
produce normal eggs, but the eggs cannot reach the uterus because the
uterine tubes are blocked or otherwise compromised.
A man may have a low sperm count, low sperm motility, sperm with an
unusually high percentage of morphological abnormalities, or sperm that
are incapable of penetrating the zona pellucida of an egg.
77. In Vitro Fertilization
A typical IVF procedure begins with egg collection. A normal ovulation
cycle produces only one oocyte, but the number can be boosted
significantly (to 10–20 oocytes) by administering a short course of
gonadotropins.
The course begins with follicle-stimulating hormone (FSH) analogs, which
support the development of multiple follicles, and ends with a luteinizing
hormone (LH) analog that triggers ovulation.
Right before the ova would be released from the ovary, they are harvested
using ultrasound-guided oocyte retrieval. In this procedure, ultrasound
allows a physician to visualize mature follicles.
78. In Vitro Fertilization
The ova are aspirated (sucked out) using a syringe.
In parallel, sperm are obtained from the male partner or from a sperm
bank.
The sperm are prepared by washing to remove seminal fluid because
seminal fluid contains a peptide, FPP (or, fertilization promoting peptide),
that—in high concentrations—prevents capacitation of the sperm.
The sperm sample is also concentrated, to increase the sperm count per
milliliter.
Next, the eggs and sperm are mixed in a petri dish.
79. In Vitro Fertilization
The ideal ratio is 75,000 sperm to one egg.
If there are severe problems with the sperm—for example, the count is
exceedingly low, or the sperm are completely nonmotile, or incapable of binding
to or penetrating the zona pellucida—a sperm can be injected into an egg. This is
called intracytoplasmic sperm injection (ICSI).
The embryos are then incubated until they either reach the eight-cell stage or the
blastocyst stage.
In the United States, fertilized eggs are typically cultured to the blastocyst stage
because this results in a higher pregnancy rate.
Finally, the embryos are transferred to a woman’s uterus using a plastic catheter
(tube).
80. In Vitro Fertilization
IVF is a relatively new and still evolving technology, and until recently it was
necessary to transfer multiple embryos to achieve a good chance of a
pregnancy.
Today, however, transferred embryos are much more likely to implant
successfully, so countries that regulate the IVF industry cap the number of
embryos that can be transferred per cycle at two.
This reduces the risk of multiple-birth pregnancies. The rate of success for
IVF is correlated with a woman’s age.
More than 40 percent of women under 35 succeed in giving birth following
IVF, but the rate drops to a little over 10 percent in women over 40.
82. Ectopic Pregnancy
Ectopic pregnancy, also called
extrauterine pregnancy, is when a
fertilized egg grows outside a woman's
uterus, somewhere else in their belly.
It can cause life-threatening bleeding and
needs medical care right away.
In more than 90% of cases, the egg
implants in a fallopian tube. This is called
a tubal pregnancy
83. Surrogate Mother
It's a woman who gets artificially inseminated with the father's sperm.
They then carry the baby and deliver it for you and your partner to
raise.
A traditional surrogate is the baby's biological mother. That's because
it was their egg that was fertilized by the father's sperm.
84. Ageing And Reproduction In The Female
Usually between the ages of 45 and 55, the ovarian supply of oocytes runs out and
the oestrogen they release therefore declines, at which point the reproductive
cycle is disrupted and fertility declines towards zero.
At the menopause, although oestrogen levels begin to fall, there is a rapid and
sustained rise in gonadotrophin secretion, as the anterior pituitary and
hypothalamus attempt to maintain activity in the failing ovaries.
From middle through to old age, the female reproductive organs, including the
breasts, progressively shrink in size.
The vulva atrophy and become more fibrous, which may predispose to infection
and malignant change. The walls of the vagina become thin and smooth with loss
of rugae and glandular secretions.
85. Ageing And Reproduction In The Male
There is no equivalent of the female menopause in the older male.
Although testosterone secretion tends to decline after age 50, leading to
a relative reduction in fertility and sexual desire, it is usually sufficient to
maintain sperm production and a man may still be able to father a child
until extreme old age.
86. Female Infertility
This common condition may be due to:
blockage of uterine tubes, often the consequence of pelvic inflammatory
disease and/or STIs
anatomical abnormalities, e.g. retroversion (tilting backwards) of the
uterus
endocrine factors; any abnormalities of the glands and hormones
governing the menstrual cycle can interfere with fertility
low body weight, e.g. in anorexia nervosa, or severe malnourishment,
and may be associated with low leptin levels
endometriosis.
87. Male Infertility
This may be due to endocrine disorders, obstruction of the deferent
duct, failure of erection or ejaculation during intercourse, vasectomy,
or suppression of spermatogenesis by, e.g. ionizing radiation,
chemotherapy and other drugs.
88. Fetal Circulation
The developing fetus obtains its oxygen and nutrients, and excretes its
waste, via the mother’s circulation.
To this end, both maternal and fetal circulations develop specific
adaptations unique to pregnancy.
Because the lungs, gastrointestinal system and kidneys do not begin to
function till after birth, certain modifications in the fetal circulation
divert blood flow to meet pre-natal requirements.
89. Placenta
This is a temporary structure that provides an interface between the
mother and fetus, and allows exchange of substances between their
circulatory systems.
It develops from the surface of the fertilized ovum embedded into the
maternal uterine endometrium.
It is expelled from the uterus during the final stage of labor soon after
birth, when it is no longer needed.
90. Fetal Adaptations
Ductus venosus: This is a continuation of the umbilical vein that returns
blood directly into the fetal inferior vena cava, and most blood, therefore,
bypasses the nonfunctional fetal liver.
Ductus arteriosus: This small vessel connects the pulmonary artery to the
descending thoracic aorta and diverts more blood into the systemic
circulation, meaning that very little blood passes through the fetal lungs.
Foramen ovale: This forms a valve-like opening allowing blood to flow
between the right and left atria, so that most blood bypasses the non-
functional fetal lungs.
91. Fetal Circulation
There are three major shunts—alternate paths for blood flow—found in the
circulatory system of the fetus.
Two of these shunts divert blood from the pulmonary to the systemic circuit,
whereas the third connects the umbilical vein to the inferior vena cava.
The first two shunts are critical during fetal life, when the lungs are compressed,
filled with amniotic fluid, and nonfunctional, and gas exchange is provided by the
placenta. These shunts close shortly after birth, however, when the newborn
begins to breathe.
The third shunt persists a bit longer but becomes nonfunctional once the umbilica
cord is severed.
92. Foramen Ovale
The foramen ovale is an opening in the interatrial septum that allows blood
to flow from the right atrium to the left atrium.
A valve associated with this opening prevents backflow of blood during the
fetal period.
As the newborn begins to breathe and blood pressure in the atria increases,
this shunt closes.
The fossa ovalis remains in the interatrial septum after birth, marking the
location of the former foramen ovale.
93. Ductus Arteriosus
The ductus arteriosus is a short, muscular vessel that connects the pulmonary trunk to
the aorta.
Most of the blood pumped from the right ventricle into the pulmonary trunk is thereby
diverted into the aorta. Only enough blood reaches the fetal lungs to maintain the
developing lung tissue.
When the newborn takes the first breath, pressure within the lungs drops dramatically,
and both the lungs and the pulmonary vessels expand.
As the amount of oxygen increases, the smooth muscles in the wall of the ductus
arteriosus constrict, sealing off the passage.
Eventually, the muscular and endothelial components of the ductus arteriosus
degenerate, leaving only the connective tissue component of the ligamentum arteriosum.
94. Ductus Venosus
The ductus venosus is a temporary blood vessel that branches from the
umbilical vein, allowing much of the freshly oxygenated blood from the
placenta—the organ of gas exchange between the mother and fetus—to
bypass the fetal liver and go directly to the fetal heart.
The ductus venosus closes slowly during the first weeks of infancy and
degenerates to become the ligamentum venosum.
95.
96. Changes At Birth
When the baby takes its first breath the lungs inflate for the first time,
increasing pulmonary blood flow.
Blood returning from the lungs increases the pressure in the left atrium,
closing the flap over the foramen ovale and preventing blood flow
between the atria.
Blood entering the right atrium is therefore diverted into the right
ventricle and into the pulmonary circulation through the pulmonary veins.
97. Changes At Birth
As the pulmonary circulation is established blood oxygen levels increase,
causing constriction and closure of the ductus arteriosus.
If these adaptations do not take place after birth, they become evident as
congenital abnormalities.
When the placental circulation ceases, soon after birth, the umbilical
vein, ductus venosus and umbilical arteries collapse, as they are no longer
required.
98.
99. SUMMARY OF HUMAN DEVELOPMENT
Development At First Week
Cleavage of zygote
Formation of morula
Transportation to uterine cavity
Transformation into blastocyst
Implantation of blastocyst in uterine cavity
100. Structure Of Blastocyst
Zona pellucida
Embryoblast(8 cell stage)
Trophoblast:
polar trophoblast(30 cell stage)
mural trophoblast(69 cell stage)
Blastocele
A fully formed blastocyst is 107 celled stage
101. Development At Second Week
A. Changes In Embryoblast
Bilaminar disc formation
hypoblast
epiblast
Prochordal plate formation
Primitive streak formation
102. B. Changes In Trophoblast
Two layers: cytotrophoblast
syncytotrophoblast
Yolk cavity
C. Formation Of Extra-embryonic Mesoderm
(primary Mesoderm)
D. Formation Of Chorion And Chorionic Cavity
E. Formation Of Amnion And Amniotic Cavity
F. Formation Of Connecting Stalk.
105. Fetal Period Of Development
Growth of body.
Maturation of organ system.
Growth in length.
Increase in weight.
Head growth
At 3rd month: Head:CRL= 1:1
At 5th month: Head:CRL= 1:3
At birth: Head:CRL= 1:4
108. Each of the three germ layers (ectoderm, mesoderm, and endoderm) forms specific
tissues and organs in the developing:
A. zygote.
B. ovum.
C. embryo.
D. fetus.
Which structure is responsible for protecting the fetus?
A. Decidua
B. Amniotic fluid
C. Corpus luteum
D. Yolk sac
Progressive enlargement of the cervical os during labor is called:
A. dilation.
B. effacement.
C. lactation.
D. differentiation.
109. Which of the following statements is true?
a. Two umbilical veins carry oxygen-depleted blood from the fetal circulation to the placenta.
b. One umbilical vein carries oxygen-rich blood from the placenta to the fetal heart.
c. Two umbilical arteries carry oxygen-depleted blood to the fetal lungs.
d. None of the above are true.
The ductus venosus is a shunt that allows ________.
a. fetal blood to flow from the right atrium to the left atrium
b. fetal blood to flow from the right ventricle to the left ventricle
c. most freshly oxygenated blood to flow into the fetal heart
d. most oxygen-depleted fetal blood to flow directly into the fetal pulmonary trunk