spermatogenesis
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The document summarizes the process of spermatogenesis in humans, which takes approximately 64 days. It involves mitotic and meiotic cell divisions that start with spermatogonia and result in the production of mature spermatozoa. During meiosis, homologous chromosomes pair up and undergo synapsis, crossing over, and segregation into haploid gametes. The spermatids then undergo spermiogenesis through morphological changes including nuclear condensation and the formation of flagella to become mature spermatozoa. Sertoli cells play an important role in nurturing spermatids and removing excess cytoplasm during their development.
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Spermatogenesis
Spermatogenesis is the process by which sperm cells develop from germ cells in the seminiferous tubules of the testis. This involves mitotic division of stem cells, meiosis to produce haploid cells, and spermiogenesis where the haploid cells differentiate into mature sperm. During spermiogenesis in mammals, an acrosomal vesicle forms and the nucleus rotates and condenses as the flagellum develops. The histones are also replaced with protamines to compact the sperm DNA and allow motility. In mice, the full process takes 34.5 days and produces over 100 million sperm per day in each testicle.
Spermatogenesis -PART 4
The document describes the process of spermatogenesis, where primordial germ cells in the testes differentiate into spermatogonia and undergo mitosis and meiosis to form haploid spermatids, which then mature into sperm cells through spermiogenesis, taking a total of 65-75 days from the beginning of spermatogenesis to the release of mature sperm.
Spermatogenesis and spermiogenesis
The document summarizes spermatogenesis and spermiogenesis, the processes by which haploid gametes are produced in males. It describes how spermatogonia undergo mitosis and meiosis to form spermatids, which then undergo cellular differentiation and remodeling through spermiogenesis to become spermatozoa or sperm. This includes the flattening and condensing of the nucleus, formation of the acrosome, growth of the tail, and shedding of excess cytoplasm. Non-ejaculatory sperm retrieval techniques for azoospermic males are also briefly discussed.
Differentiation and maturation of spermatogenic stem cell
Spermatogenesis is the process by which spermatogenic stem cells in the testes mature and develop into mature male gametes called spermatozoa. It occurs in three stages - spermatocytogenesis where spermatogonia form spermatocytes, spermatidogenesis where spermatocytes form spermatids, and spermiogenesis where spermatids undergo morphological changes to form spermatozoa. The process is controlled by hormones like testosterone and takes place in the seminiferous tubules of the testes over 64 days from start to finish.
Spermatogenesis rku
Spermatogenesis is the process by which sperm cells are formed from germ cells in the seminiferous tubules of the testes. It occurs in three phases: spermatocytogenesis involves mitosis, meiosis reduces the cells to half the normal number of chromosomes, and spermiogenesis transforms spermatids into mature spermatozoa through changes like acrosome formation and tail growth. The process begins with stem cell spermatogonia and progresses through spermatocytes and spermatids before mature sperm are released in a process called spermiation.
Spermatogenesis and oogenesis
1) Spermatogenesis and oogenesis both involve meiosis to produce haploid gametes from diploid germ cells.
2) In spermatogenesis, spermatogonia undergo mitosis and differentiate into spermatocytes, then spermatids through meiosis. Spermiogenesis transforms spermatids into mature sperm.
3) In oogenesis, oogonia become primary oocytes that arrest in prophase I until after puberty. A few complete meiosis I and II if fertilized, becoming ovulated ova.
Lesson 6 Spermatogenesis and Oogenesis
Spermatogenesis and oogenesis are the processes by which sperm and egg cells are produced through cell division and maturation. Spermatogenesis occurs within the coiled tubes of the testes and involves successive cell divisions through mitosis and meiosis to produce mature sperm cells continuously from adolescence to around age 50. Oogenesis takes place within the ovaries and involves a prolonged development of oocytes through meiosis, with only one oocyte maturing into a single egg cell per monthly cycle until menopause.
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Spermatogenesis
Spermatogenesis is the process by which sperm cells develop from germ cells in the seminiferous tubules of the testis. This involves mitotic division of stem cells, meiosis to produce haploid cells, and spermiogenesis where the haploid cells differentiate into mature sperm. During spermiogenesis in mammals, an acrosomal vesicle forms and the nucleus rotates and condenses as the flagellum develops. The histones are also replaced with protamines to compact the sperm DNA and allow motility. In mice, the full process takes 34.5 days and produces over 100 million sperm per day in each testicle.
Spermatogenesis -PART 4
The document describes the process of spermatogenesis, where primordial germ cells in the testes differentiate into spermatogonia and undergo mitosis and meiosis to form haploid spermatids, which then mature into sperm cells through spermiogenesis, taking a total of 65-75 days from the beginning of spermatogenesis to the release of mature sperm.
Spermatogenesis and spermiogenesis
The document summarizes spermatogenesis and spermiogenesis, the processes by which haploid gametes are produced in males. It describes how spermatogonia undergo mitosis and meiosis to form spermatids, which then undergo cellular differentiation and remodeling through spermiogenesis to become spermatozoa or sperm. This includes the flattening and condensing of the nucleus, formation of the acrosome, growth of the tail, and shedding of excess cytoplasm. Non-ejaculatory sperm retrieval techniques for azoospermic males are also briefly discussed.
Differentiation and maturation of spermatogenic stem cell
Spermatogenesis is the process by which spermatogenic stem cells in the testes mature and develop into mature male gametes called spermatozoa. It occurs in three stages - spermatocytogenesis where spermatogonia form spermatocytes, spermatidogenesis where spermatocytes form spermatids, and spermiogenesis where spermatids undergo morphological changes to form spermatozoa. The process is controlled by hormones like testosterone and takes place in the seminiferous tubules of the testes over 64 days from start to finish.
Spermatogenesis rku
Spermatogenesis is the process by which sperm cells are formed from germ cells in the seminiferous tubules of the testes. It occurs in three phases: spermatocytogenesis involves mitosis, meiosis reduces the cells to half the normal number of chromosomes, and spermiogenesis transforms spermatids into mature spermatozoa through changes like acrosome formation and tail growth. The process begins with stem cell spermatogonia and progresses through spermatocytes and spermatids before mature sperm are released in a process called spermiation.
Spermatogenesis and oogenesis
1) Spermatogenesis and oogenesis both involve meiosis to produce haploid gametes from diploid germ cells.
2) In spermatogenesis, spermatogonia undergo mitosis and differentiate into spermatocytes, then spermatids through meiosis. Spermiogenesis transforms spermatids into mature sperm.
3) In oogenesis, oogonia become primary oocytes that arrest in prophase I until after puberty. A few complete meiosis I and II if fertilized, becoming ovulated ova.
Lesson 6 Spermatogenesis and Oogenesis
Spermatogenesis and oogenesis are the processes by which sperm and egg cells are produced through cell division and maturation. Spermatogenesis occurs within the coiled tubes of the testes and involves successive cell divisions through mitosis and meiosis to produce mature sperm cells continuously from adolescence to around age 50. Oogenesis takes place within the ovaries and involves a prolonged development of oocytes through meiosis, with only one oocyte maturing into a single egg cell per monthly cycle until menopause.
Spermatogenesis
This ppt includes sperm formation, seminiferous tubule, anatomy of sperm, spermatogonia, spermatocytogenesis, and spermiogenesis.
gametogenesis
Spermatogenesis is the process by which sperm are produced in the seminiferous tubules of the testes over 65-70 days. It begins with spermatogonia that undergo mitosis and meiosis to form haploid spermatids from diploid spermatocytes. Sertoli cells secrete fluid to nourish spermatids and protect them, while interstitial cells secrete testosterone. Oogenesis similarly occurs in the ovaries, forming oocytes or eggs over a woman's lifetime from primary oocytes present at birth that undergo meiosis to become haploid secondary oocytes if fertilized.
Spermatogenesis
Spermatogenesis is the process by which germ cells differentiate into spermatozoa. It occurs within the seminiferous tubules of the testis and can be divided into three main phases: proliferation of spermatogonia, meiotic reduction division producing spermatocytes, and differentiation of spermatids into spermatozoa. Spermatogenesis progresses through cycles of the seminiferous epithelium, where each stage is defined by the association of germ cells at a specific developmental phase. Repeated cycles ensure continuous production of spermatozoa.
Gametogenesis
Gametogenesis is the process by which haploid gametes are formed from diploid germ cells in the gonads. There are two types: spermatogenesis and oogenesis. Spermatogenesis occurs in the testes and involves the formation of sperm from spermatogonia over 74 days, involving multiplication, growth, and maturation phases. Oogenesis occurs in the ovaries and also involves three phases to form ova from oogonia. The resulting gametes, sperm and ovum, differ in structure according to their roles in fertilization. Sperm are small, motile cells specialized for movement, while ovum are larger stationary cells specialized to receive sperm and support development.
Lecture3
The document provides an overview of embryology, discussing key phases of human development from fertilization through birth. It describes gamete formation (spermatogenesis and oogenesis), the stages of pre-embryonic development (zygote, morula, blastocyst), and the prenatal and postnatal developmental periods. The structure and origin of male and female gametes are also summarized.
Gametogenesis
The document describes several key processes in human development:
1. Gamete production and spermatogenesis/oogenesis which involve the formation of sperm and eggs through meiosis in the gonads.
2. Fertilization, which requires the sperm penetrating the egg's jelly coat and plasma membrane fusing with the egg's plasma membrane.
3. Cleavage, where the zygote rapidly divides through mitosis to form a morula then blastula.
4. Gastrulation creates the three germ layers and primitive streak that patterns the embryo.
5. Neurulation forms the neural tube which later becomes the brain and spinal cord through primary then secondary neurulation.
Fertilization
Fertilization involves the fusion of an egg and sperm, combining their genetic material. This process activates the egg and initiates embryonic development. Key events include chemoattraction of sperm to the egg, binding and fusion of gametes, and prevention of polyspermy. Fusion results in the formation of a single cell with a combined genome from both parent cells. This triggers metabolic changes in the egg and causes its nuclei to fuse, forming a zygote capable of initiating development of a new organism.
Gametogenesis project
Spermatogenesis and oogenesis are the processes by which male and female gametes are formed through meiosis. Spermatogenesis involves spermatogonia developing into spermatocytes and then spermatids and ultimately four small, haploid sperm cells. Oogenesis involves oogonia developing into primary oocytes and then secondary oocytes, with one egg and three polar bodies produced along with conserved cytoplasm in the single egg cell. The main differences are that spermatogenesis produces four small gametes while oogenesis produces one large gamete and polar bodies, and oogenesis can function in fertilization before meiosis is complete unlike spermatogenesis.
SPERMATOGENESIS & Stem cells
Spermatogenesis is the process by which spermatogonial stem cells in the seminiferous tubules of the testes proliferate and differentiate into mature sperm. Spermatogonial stem cells self-renew to maintain spermatogenesis throughout a male's life and can also differentiate into sperm. These stem cells can be identified by markers and cultured in vitro while maintaining their stem cell properties. Transplantation of spermatogonial stem cells into testes has resulted in donor-derived spermatogenesis, offering potential applications such as preservation of fertility.
Gametogenisis, Fertilization
1) Gametogenesis is the process by which gametes (eggs and sperm) are formed through meiosis in both males and females. Oogenesis occurs in females and produces eggs, while spermatogenesis produces sperm in males.
2) Oogenesis begins with primordial germ cells that develop into oocytes through meiosis. At puberty, a few oocytes complete the first meiotic division and arrest until ovulation. Spermatogenesis occurs through meiosis within the testes, producing spermatids that transform into sperm.
3) Fertilization is the fusion of an egg and sperm. It involves the approximation and fusion of the gametes, restoring the diploid number of chromosomes
Spermatogenesis
Spermatogenesis is the process by which sperm cells are produced. It involves the division and differentiation of germ cells within the seminiferous tubules of the testes. High temperatures can damage spermatogenesis, particularly affecting primary spermatocytes. Vitamin E and A both play roles in spermatogenesis, with deficiencies leading to disrupted or incomplete sperm production and potential infertility. Maintaining proper vitamin levels and avoiding high temperatures are important for normal spermatogenesis.
Developmental biology
Sexual reproduction involves combining the chromosomes of two parents so that no two offspring are identical. Most organisms reproduce sexually. The evolution of sex is puzzling given its costs, but it provides genetic variation that helps populations adapt to changing environments, as proposed by the Red Queen Hypothesis. Meiosis during gamete formation and fertilization contributes to this genetic variation between offspring.
Gametogenesis
Gametogenesis is the process by which haploid gametes are formed through meiosis and differentiation of diploid or haploid cells. It occurs in the gonads through meiosis of diploid germ cells or mitosis of haploid germ cells. This results in various gametes. Spermatogenesis and oogenesis are the specific processes for male and female gamete formation, respectively, which both start from diploid germ cells and end with haploid gametes through meiosis.
Leydig cell
Leydig cells are found in the testicles and produce the hormone testosterone when stimulated by luteinizing hormone from the pituitary gland. They release testosterone and other androgens which leads to male characteristics. Leydig cells have a polyhedral shape with a large nucleus and lipid-filled vesicles. They are named after Franz Leydig who discovered them in 1850.
Embryology Lecture 3 spermatogenesis
Spermatogenesis is the process by which sperm cells are produced in the testes in males. It involves the transformation of spermatogonia into mature sperm through two stages: spermatocytogenesis where primordial germ cells develop into spermatids, and spermiogenesis where spermatids are transformed into mature sperm. In humans, it takes approximately 74 days to complete and produces around 300 million sperm cells daily. Oogenesis is the similar process that occurs in females within the ovaries to produce eggs.
Embryology full note2
1) Human development begins with the fertilization of an egg (oocyte) by sperm, forming a single-celled zygote. Through processes such as cell division, differentiation, growth and rearrangement over 9 months, the zygote develops into a baby.
2) Development is divided into prenatal (before birth) and postnatal (after birth) periods, with major developmental changes occurring during embryonic, fetal, infant and childhood stages.
3) Both male and female gametes are produced through meiosis within the ovaries and testes, respectively, reducing the chromosome count so that fertilization restores the normal diploid number.
11.4 production of gametes
The document summarizes the processes of spermatogenesis and oogenesis. It describes how sperm are produced in the testes through mitosis, meiosis and differentiation. Millions of sperm are produced daily starting at puberty. Oogenesis occurs in the ovaries, with one egg maturing each month through meiosis. Only one egg is produced per month from fetal development to menopause. The three hormones that regulate spermatogenesis - FSH, LH, and testosterone - are also outlined.
Gametogenesis
The document discusses sex cell differentiation and gamete formation in humans and other animals. It covers the processes of oogenesis and spermatogenesis, including the migration of primordial germ cells and proliferation of eggs and sperm. It also describes fertilization, including the structures and stages of egg and sperm cells, their fusion during conception, and the early cleavage and differentiation stages of embryonic development.
01 Gametogenesis
The document summarizes the male and female reproductive systems in humans. It describes the key organs involved in sexual reproduction, including the ovaries and testes where gametes are produced, as well as the organs involved in transport and development of eggs and sperm. It also provides details on gametogenesis, the process of forming eggs and sperm, including spermatogenesis in the testes and oogenesis in the ovaries.
Gametogenesis
Gametogenesis is the process by which organisms produce gametes (reproductive cells). In humans, gametogenesis occurs through meiosis in the gonads to produce either sperm or eggs with half the number of chromosomes.
Spermatogenesis is the process where special somatic cells in the testes undergo meiosis and maturation to form sperm. During oogenesis in females, follicles in the ovaries develop through the ovarian cycle, with one follicle undergoing maturation and ovulation to release an egg. If fertilization occurs, the remaining follicle forms the corpus luteum to secrete progesterone.
The uterine cycle is regulated by hormones and involves the menstrual, proliferative, and secretory phases. It prepares the uterus for potential implantation
The Cell Cycle Mitosis 2015
This image shows plant cell mitosis in telophase. Key indications:
- Cell plate forming between two nuclei - characteristic of plant cell cytokinesis
- No cleavage furrow as would be seen in animal cells
So in summary, this image shows a plant cell undergoing telophase/cytokinesis stage of mitosis.
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The document discusses the process of cell division, including the two main types (mitosis and meiosis). It explains DNA structure and replication, the stages of mitosis (prophase, metaphase, anaphase, telophase), and the cell cycle stages of interphase and the M phase. The goal of cell division is to make copies of cells for growth, tissue repair, and reproduction.
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Spermatogenesis
This ppt includes sperm formation, seminiferous tubule, anatomy of sperm, spermatogonia, spermatocytogenesis, and spermiogenesis.
gametogenesis
Spermatogenesis is the process by which sperm are produced in the seminiferous tubules of the testes over 65-70 days. It begins with spermatogonia that undergo mitosis and meiosis to form haploid spermatids from diploid spermatocytes. Sertoli cells secrete fluid to nourish spermatids and protect them, while interstitial cells secrete testosterone. Oogenesis similarly occurs in the ovaries, forming oocytes or eggs over a woman's lifetime from primary oocytes present at birth that undergo meiosis to become haploid secondary oocytes if fertilized.
Spermatogenesis
Spermatogenesis is the process by which germ cells differentiate into spermatozoa. It occurs within the seminiferous tubules of the testis and can be divided into three main phases: proliferation of spermatogonia, meiotic reduction division producing spermatocytes, and differentiation of spermatids into spermatozoa. Spermatogenesis progresses through cycles of the seminiferous epithelium, where each stage is defined by the association of germ cells at a specific developmental phase. Repeated cycles ensure continuous production of spermatozoa.
Gametogenesis
Gametogenesis is the process by which haploid gametes are formed from diploid germ cells in the gonads. There are two types: spermatogenesis and oogenesis. Spermatogenesis occurs in the testes and involves the formation of sperm from spermatogonia over 74 days, involving multiplication, growth, and maturation phases. Oogenesis occurs in the ovaries and also involves three phases to form ova from oogonia. The resulting gametes, sperm and ovum, differ in structure according to their roles in fertilization. Sperm are small, motile cells specialized for movement, while ovum are larger stationary cells specialized to receive sperm and support development.
Lecture3
The document provides an overview of embryology, discussing key phases of human development from fertilization through birth. It describes gamete formation (spermatogenesis and oogenesis), the stages of pre-embryonic development (zygote, morula, blastocyst), and the prenatal and postnatal developmental periods. The structure and origin of male and female gametes are also summarized.
Gametogenesis
The document describes several key processes in human development:
1. Gamete production and spermatogenesis/oogenesis which involve the formation of sperm and eggs through meiosis in the gonads.
2. Fertilization, which requires the sperm penetrating the egg's jelly coat and plasma membrane fusing with the egg's plasma membrane.
3. Cleavage, where the zygote rapidly divides through mitosis to form a morula then blastula.
4. Gastrulation creates the three germ layers and primitive streak that patterns the embryo.
5. Neurulation forms the neural tube which later becomes the brain and spinal cord through primary then secondary neurulation.
Fertilization
Fertilization involves the fusion of an egg and sperm, combining their genetic material. This process activates the egg and initiates embryonic development. Key events include chemoattraction of sperm to the egg, binding and fusion of gametes, and prevention of polyspermy. Fusion results in the formation of a single cell with a combined genome from both parent cells. This triggers metabolic changes in the egg and causes its nuclei to fuse, forming a zygote capable of initiating development of a new organism.
Gametogenesis project
Spermatogenesis and oogenesis are the processes by which male and female gametes are formed through meiosis. Spermatogenesis involves spermatogonia developing into spermatocytes and then spermatids and ultimately four small, haploid sperm cells. Oogenesis involves oogonia developing into primary oocytes and then secondary oocytes, with one egg and three polar bodies produced along with conserved cytoplasm in the single egg cell. The main differences are that spermatogenesis produces four small gametes while oogenesis produces one large gamete and polar bodies, and oogenesis can function in fertilization before meiosis is complete unlike spermatogenesis.
SPERMATOGENESIS & Stem cells
Spermatogenesis is the process by which spermatogonial stem cells in the seminiferous tubules of the testes proliferate and differentiate into mature sperm. Spermatogonial stem cells self-renew to maintain spermatogenesis throughout a male's life and can also differentiate into sperm. These stem cells can be identified by markers and cultured in vitro while maintaining their stem cell properties. Transplantation of spermatogonial stem cells into testes has resulted in donor-derived spermatogenesis, offering potential applications such as preservation of fertility.
Gametogenisis, Fertilization
1) Gametogenesis is the process by which gametes (eggs and sperm) are formed through meiosis in both males and females. Oogenesis occurs in females and produces eggs, while spermatogenesis produces sperm in males.
2) Oogenesis begins with primordial germ cells that develop into oocytes through meiosis. At puberty, a few oocytes complete the first meiotic division and arrest until ovulation. Spermatogenesis occurs through meiosis within the testes, producing spermatids that transform into sperm.
3) Fertilization is the fusion of an egg and sperm. It involves the approximation and fusion of the gametes, restoring the diploid number of chromosomes
Spermatogenesis
Spermatogenesis is the process by which sperm cells are produced. It involves the division and differentiation of germ cells within the seminiferous tubules of the testes. High temperatures can damage spermatogenesis, particularly affecting primary spermatocytes. Vitamin E and A both play roles in spermatogenesis, with deficiencies leading to disrupted or incomplete sperm production and potential infertility. Maintaining proper vitamin levels and avoiding high temperatures are important for normal spermatogenesis.
Developmental biology
Sexual reproduction involves combining the chromosomes of two parents so that no two offspring are identical. Most organisms reproduce sexually. The evolution of sex is puzzling given its costs, but it provides genetic variation that helps populations adapt to changing environments, as proposed by the Red Queen Hypothesis. Meiosis during gamete formation and fertilization contributes to this genetic variation between offspring.
Gametogenesis
Gametogenesis is the process by which haploid gametes are formed through meiosis and differentiation of diploid or haploid cells. It occurs in the gonads through meiosis of diploid germ cells or mitosis of haploid germ cells. This results in various gametes. Spermatogenesis and oogenesis are the specific processes for male and female gamete formation, respectively, which both start from diploid germ cells and end with haploid gametes through meiosis.
Leydig cell
Leydig cells are found in the testicles and produce the hormone testosterone when stimulated by luteinizing hormone from the pituitary gland. They release testosterone and other androgens which leads to male characteristics. Leydig cells have a polyhedral shape with a large nucleus and lipid-filled vesicles. They are named after Franz Leydig who discovered them in 1850.
Embryology Lecture 3 spermatogenesis
Spermatogenesis is the process by which sperm cells are produced in the testes in males. It involves the transformation of spermatogonia into mature sperm through two stages: spermatocytogenesis where primordial germ cells develop into spermatids, and spermiogenesis where spermatids are transformed into mature sperm. In humans, it takes approximately 74 days to complete and produces around 300 million sperm cells daily. Oogenesis is the similar process that occurs in females within the ovaries to produce eggs.
Embryology full note2
1) Human development begins with the fertilization of an egg (oocyte) by sperm, forming a single-celled zygote. Through processes such as cell division, differentiation, growth and rearrangement over 9 months, the zygote develops into a baby.
2) Development is divided into prenatal (before birth) and postnatal (after birth) periods, with major developmental changes occurring during embryonic, fetal, infant and childhood stages.
3) Both male and female gametes are produced through meiosis within the ovaries and testes, respectively, reducing the chromosome count so that fertilization restores the normal diploid number.
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The document summarizes the processes of spermatogenesis and oogenesis. It describes how sperm are produced in the testes through mitosis, meiosis and differentiation. Millions of sperm are produced daily starting at puberty. Oogenesis occurs in the ovaries, with one egg maturing each month through meiosis. Only one egg is produced per month from fetal development to menopause. The three hormones that regulate spermatogenesis - FSH, LH, and testosterone - are also outlined.
Gametogenesis
The document discusses sex cell differentiation and gamete formation in humans and other animals. It covers the processes of oogenesis and spermatogenesis, including the migration of primordial germ cells and proliferation of eggs and sperm. It also describes fertilization, including the structures and stages of egg and sperm cells, their fusion during conception, and the early cleavage and differentiation stages of embryonic development.
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The document summarizes the male and female reproductive systems in humans. It describes the key organs involved in sexual reproduction, including the ovaries and testes where gametes are produced, as well as the organs involved in transport and development of eggs and sperm. It also provides details on gametogenesis, the process of forming eggs and sperm, including spermatogenesis in the testes and oogenesis in the ovaries.
Gametogenesis
Gametogenesis is the process by which organisms produce gametes (reproductive cells). In humans, gametogenesis occurs through meiosis in the gonads to produce either sperm or eggs with half the number of chromosomes.
Spermatogenesis is the process where special somatic cells in the testes undergo meiosis and maturation to form sperm. During oogenesis in females, follicles in the ovaries develop through the ovarian cycle, with one follicle undergoing maturation and ovulation to release an egg. If fertilization occurs, the remaining follicle forms the corpus luteum to secrete progesterone.
The uterine cycle is regulated by hormones and involves the menstrual, proliferative, and secretory phases. It prepares the uterus for potential implantation
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This image shows plant cell mitosis in telophase. Key indications:
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- No cleavage furrow as would be seen in animal cells
So in summary, this image shows a plant cell undergoing telophase/cytokinesis stage of mitosis.
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Spermatogenesis is the process by which mature sperm cells are produced from spermatogonial stem cells. It involves mitotic divisions that increase the number of sperm cells, followed by two meiotic divisions that reduce the chromosome number. Over 64 days in humans, a single spermatogonial cell undergoes mitosis to produce 96 spermatids, which then undergo spermiogenesis to mature into motile spermatozoa through a series of morphological and biochemical changes. Sertoli cells within the seminiferous tubules nurture and transport maturing spermatids and remove excess cytoplasm.
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Spermatogenesis is the process by which mature sperm cells are produced from spermatogonial stem cells. It involves mitotic divisions that increase the number of sperm cells, followed by two meiotic divisions that reduce the chromosome number. Over 64 days in humans, a single spermatogonial cell undergoes mitosis to produce 96 spermatids, which then undergo spermiogenesis to mature into motile spermatozoa through a series of morphological and biochemical changes. Sertoli cells within the seminiferous tubules nurture and transport maturing spermatids and remove excess cytoplasm, helping to produce fully formed sperm.
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Cell reproduction occurs through mitosis and meiosis. Mitosis produces identical daughter cells and occurs in somatic cells for growth and repair. Meiosis reduces the chromosome number by half and produces gametes involved in sexual reproduction, where the union of male and female gametes leads to fertilization and the formation of a new individual with a mix of genetic material.
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1. The document describes the cell cycle, including the stages of interphase (G1, S, G2 phases) and mitosis (prophase, metaphase, anaphase, telophase). It also describes meiosis, which produces haploid gametes through two nuclear divisions.
2. Key aspects of meiosis include homologous chromosomes pairing and crossing over in prophase I, followed by separation of homologous chromosomes in anaphase I. The second meiotic division separates sister chromatids.
3. Meiosis results in four haploid cells from one diploid cell, and maintains the chromosome number between generations through the fusion of haploid gametes during fertilization.
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Cell division can occur via mitosis or meiosis. Mitosis produces two identical daughter cells with the same number of chromosomes as the parent cell and is used for growth and repair. Meiosis produces four haploid gametes through two cell divisions, reducing the chromosome number by half to allow sexual reproduction. Fertilization of an egg and sperm restores the full chromosome number.
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An introduction to mitosis and meiosis. And full definition of this topic. Learn easy to simple English, It's to very interested
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The document summarizes the cell cycle process of mitosis and meiosis. It describes that the cell cycle consists of interphase and mitosis or meiosis. Interphase is divided into G1, S, and G2 phases where the cell grows and duplicates its contents in preparation for division. Mitosis is the process where the cell nucleus divides into two identical nuclei through the stages of prophase, metaphase, anaphase and telophase. Meiosis produces gametes through two cell divisions and involves homologous chromosome pairing, crossing over and separation into haploid cells with one chromosome of each type.
AP Cell Cycle-Mitosis and Meiosis (1).ppt
The document summarizes the cell cycle process of mitosis and meiosis. It describes that the cell cycle consists of interphase and mitosis or meiosis. Interphase is divided into G1, S, and G2 phases where the cell grows and duplicates its contents in preparation for division. Mitosis is the process where the cell nucleus divides into two identical nuclei through the stages of prophase, metaphase, anaphase and telophase. Meiosis produces gametes through two cell divisions and involves homologous chromosome pairing, crossing over and separation into haploid cells with one chromosome of each type.
AP Cell Cycle-Mitosis and Meiosissss.ppt
The document summarizes the cell cycle process of mitosis and meiosis. It describes that the cell cycle consists of interphase, where the cell grows and organelles double, followed by either mitosis or meiosis. Mitosis involves the division of the nucleus into two identical daughter cells through the stages of prophase, metaphase, anaphase and telophase. Meiosis results in four haploid daughter cells through two rounds of division, including homologous chromosome pairing and separation in meiosis I and sister chromatid separation in meiosis II.
Mitosis and Meiosis.ppt
The document summarizes the cell cycle process of mitosis and meiosis. It describes that the cell cycle consists of interphase and mitosis or meiosis. Interphase is divided into G1, S, and G2 phases where the cell grows and duplicates its contents in preparation for division. Mitosis is the process where the cell nucleus divides into two identical nuclei through the stages of prophase, metaphase, anaphase and telophase. Meiosis produces gametes through two cell divisions and involves homologous chromosome pairing, crossing over and separation into haploid cells with one chromosome of each type.
AP Cell Cycle-Mitosis and Meiosis.ppt
The document summarizes the cell cycle process of mitosis and meiosis. It describes that the cell cycle consists of interphase and mitosis or meiosis. Interphase is divided into G1, S, and G2 phases where the cell grows and duplicates its contents in preparation for division. Mitosis is then described as the process where the cell nucleus divides into two identical nuclei through the stages of prophase, metaphase, anaphase and telophase. Meiosis is then summarized as the process that forms gametes through two cell divisions, reducing the chromosome number by half to produce four haploid cells from one original diploid cell.
CELL DIVISION- Decoding Cell Division: The Dance of Life's Continuity
Decoding Cell Division: The Dance of Life's Continuity
Step into the mesmerizing world of cell division with our illuminating SlideShare presentation. From the elegant choreography of mitosis to the intricacies of meiosis, witness the remarkable processes that underpin life's continuity and diversity.
In this captivating presentation, we delve deep into the mechanisms of cell division, unraveling the stages and significance of mitosis and meiosis. Explore how cells meticulously replicate their DNA, segregate their chromosomes, and orchestrate their division to ensure the transmission of genetic information with precision and fidelity.
Through vivid illustrations, clear explanations, and real-world examples, we illuminate the significance of cell division in growth, development, and reproduction. Gain a newfound understanding of how errors in cell division can lead to diseases like cancer and genetic disorders, and learn about the cutting-edge research driving advancements in this field.
Whether you're a student, educator, or enthusiast of life sciences, our presentation offers valuable insights into one of the most fundamental processes of life. Join us as we unravel the mysteries of cell division and marvel at the beauty and complexity of nature's continuity.
Don't miss this opportunity to deepen your knowledge and appreciation of cell biology. Embark on a journey into the heart of cell division and discover the dance of life's continuity unfolding before your eyes.
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CELL DIVISION- Decoding Cell Division: The Dance of Life's Continuity
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Themajorcausesofdeteriorationinstorage
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Centrifugation is a powerful technique used in laboratories to separate components of a heterogeneous mixture based on their density. This process utilizes centrifugal force to rapidly spin samples, causing denser particles to migrate outward more quickly than lighter ones. As a result, distinct layers form within the sample tube, allowing for easy isolation and purification of target substances.
Candidate young stellar objects in the S-cluster: Kinematic analysis of a sub...
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+
53.13485
−
27.82088
with a host spectroscopic redshift of
2.903
±
0.007
. The transient was identified in deep James Webb Space Telescope (JWST)/NIRCam imaging from the JWST Advanced Deep Extragalactic Survey (JADES) program. Photometric and spectroscopic followup with NIRCam and NIRSpec, respectively, confirm the redshift and yield UV-NIR light-curve, NIR color, and spectroscopic information all consistent with a Type Ia classification. Despite its classification as a likely SN Ia, SN 2023adsy is both fairly red (
�
(
�
−
�
)
∼
0.9
) despite a host galaxy with low-extinction and has a high Ca II velocity (
19
,
000
±
2
,
000
km/s) compared to the general population of SNe Ia. While these characteristics are consistent with some Ca-rich SNe Ia, particularly SN 2016hnk, SN 2023adsy is intrinsically brighter than the low-
�
Ca-rich population. Although such an object is too red for any low-
�
cosmological sample, we apply a fiducial standardization approach to SN 2023adsy and find that the SN 2023adsy luminosity distance measurement is in excellent agreement (
≲
1
�
) with
Λ
CDM. Therefore unlike low-
�
Ca-rich SNe Ia, SN 2023adsy is standardizable and gives no indication that SN Ia standardized luminosities change significantly with redshift. A larger sample of distant SNe Ia is required to determine if SN Ia population characteristics at high-
�
truly diverge from their low-
�
counterparts, and to confirm that standardized luminosities nevertheless remain constant with redshift.
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Microbial interaction
Microorganisms interacts with each other and can be physically associated with another organisms in a variety of ways.
One organism can be located on the surface of another organism as an ectobiont or located within another organism as endobiont.
Microbial interaction may be positive such as mutualism, proto-cooperation, commensalism or may be negative such as parasitism, predation or competition
Types of microbial interaction
Positive interaction: mutualism, proto-cooperation, commensalism
Negative interaction: Ammensalism (antagonism), parasitism, predation, competition
I. Mutualism:
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Mutualistic relationship is very specific where one member of association cannot be replaced by another species.
Mutualism require close physical contact between interacting organisms.
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Mutualistic relationship between organisms allows them to act as a single organism.
Examples of mutualism:
i. Lichens:
Lichens are excellent example of mutualism.
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II. Syntrophism:
It is an association in which the growth of one organism either depends on or improved by the substrate provided by another organism.
In syntrophism both organism in association gets benefits.
Compound A
Utilized by population 1
Compound B
Utilized by population 2
Compound C
utilized by both Population 1+2
Products
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ii. Lactobacillus arobinosus and Enterococcus faecalis:
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Classification
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Masking and demasking reagents
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Masking agent, Demasking agents
formation of complex
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Instrumental Techniques-Photometry
Potentiometry
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Complex titration with EDTA.
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spermatogenesis
- 3. Spermatogenic cycle A1 2A1 Mitosis 3A2A1 Mitosis 6B1 Mitosis 12B2 Mitosis 24 primary spermatocytes Mitosis 48 secondary spermatocytes Meiosis I 96 spermatids Meiosis II 96 mature spermatozoa Spermiogenesis = Spermateleosis = Spermatozoan metamorphosis First meiotic division lasts several weeks in humans Second meiotic division takes about 8 hours in humans The following is an example of how the number of spermatozoa is increased by repetitive mitotic divisions of spermatogonial cells followed by the two meiotic divisions. There are actually more than 4 types of spermatogonia, so the actual number of mature spermatozoa originating from the initial division of a type A1 spermatogonium is actually greater than 96. Reductional division Equational division An entire spermatogenic cycle in humans takes about 64 days. The maturing spermatids remain attached by cytoplasmic bridges as they mature => syncytium
- 5. Let’s think about meiosis: 1. Where did the chromosomes come from? 2. Why are there pairs of chromosomes? 3. How must the chromosomes segregate if you’re going to have sexual reproduction? What do you have to end up with in he gametes? 4. How would you accomplish this in two divisions?
- 6. I XReplicated Chromosome Dyad - Two Chromatids Replication Single Chromosome Monad IIHomologous Pair M P CHROMOSOME TERMINOLOGY M X P X Replication Replicated Homologous Pair Synapsis X M X P Homologous Gene Loci Replicated Homologous Gene Loci Tetrad = Two Synapsed replicated Homologues
- 7. Meiosis Genetic Content (n) and Chromosome Number (c) Diploid genetic content - 2n - the 2 represents the fact that each gene locus can contain a maximum of 2 different gene alleles (e.g., one dominant and one recessive). “n” is the total number of homologous gene loci in the genome (a very big number). Diploid chromosome number - 2c - the 2 represents the fact that there are 2 chromosomes in each homologous pair. “c” is the total number of homologous pairs of chromosomes. P P M M PPMM Genetic content vs Chromosome number
- 9. Leptotene Chromosomes start to condense, dyads (replicated chromosomes) of homologous pairs first become visible as linear strings of DNA Zygotene Chromosomes condense further. Dyads of homologous pairs of chromosomes pair- up and their chromatids start to undergo synapsis. Pachytene Synapsis is completed with synapsed chromosomes forming tetrads. Cross-over takes place. Synapsed chromosomes thicken up (pachy - thick). Diplotene Chromosomes condense further, Desynapsis begins. Chromatids of homologous pairs of chromosomes remain connected at chiasmata where cross-over may have occurred. Diakinesis Chromosomes condense even further. Separating tetrads form strange shapes like crosses, fish, infinity signs as chiasmata move toward the ends of the paired chromatids of the homologous chromosomes (called terminalization). Eventually desynapsis is completed and the homologues separate from one and other completely and metaphase begins. First meiotic prophase:
- 10. Spermatogenesis in an Invertebrate - grasshopper
- 11. Figure on Page 89 of your text Spermatogenesis in Vertebrates
- 12. Spermatogenesis in Vertebrates Figure of rat testis in digital lab manual
- 13. Spermatogenesis in Vertebrates Figure of human testis in digital lab manual
- 14. Spermiogenesis 1. Nucleus condenses (chromosomes condense and nuclear sap is removed) 2. Flagellum develops 3. Spermatocyte elongates 4. Acrosome formed from golgi body 5. Mitochondria aggregate around base of forming flagellum 6. Mitochondria fuse to form supermitochondrion (in humans) 7. Most of cytoplasm is shed and phagocytosed by sertoli cell (tubulobulbar processes)
- 15. 1. Nucleus condenses (chromosomes condense and nuclear sap is removed) 2. Flagellum develops 3. Spermatocyte elongates 4. Acrosome formed from golgi body 5. Mitochondria aggregate around base of forming flagellum 6. Mitochondria fuse to form supermitochondrion (in humans) 7. Most of cytoplasm is shed and phagocytosed by sertoli cell (tubulobulbar processes)
- 16. Sertoli cell function 1. Remove excess cytoplasm from developing spermatid - tubulobulbar processes 2. Move spermatids toward the lumen of the seminiferous tubules - ectoplasmic specializations 3. Nurture and mediate maturation of spermatids 4. Segregate groups of developing gametes 5. Secrete fluid to transport sperm in reproductive tract 6. Secrete hormones and other factors a. Embryonic - anti-mullarian hormone b. Adult (1) inhibin (inhibits FSH production) (2) estrogen - may act to inhibit GnRH production by basal hypothalamus (3) Other factor (not a hormone) - androgen binding protein (helps transport androgens from interstitial fluid into seminiferous tubule - promotes spermatogenesis) http://education.vetmed.vt.edu/Curriculum/VM8054/Labs/Lab27/EXAMPLES/EXSERTOL.HTM