The document summarizes the evolution of kidneys and urino-genital ducts in vertebrates. It describes how the pronephros, mesonephros and metanephros kidney systems develop and how their associated ducts give rise to the male and female reproductive tracts. It explains that in females, the Müllerian ducts form the oviducts, while in males the mesonephric ducts form parts of the reproductive system or are reduced. The kidneys and ducts show adaptations for waste excretion, sperm transport, and supporting embryo development across vertebrate groups.
The primitive blueprint for the heart and circulatory system emerged with the arrival of the third mesodermal germ layer in bilaterians. Since then, hearts in animals have evolved from a single layered tube to a multiple chambered heart in due course of time.
INTRODUCTION
The jaw (Upper and lower) is any opposable articulated structure at the entrance of the mouth.
It is typically used for grasping and manipulating food.
Jaw suspension means the fusion of upper jaw and lower jaw or skull for efficient biting.
There are different ways in which these attachments are attained depending upon the modifications in visceral arches in vertebrates.
In most vertebrates, the jaws are bony or cartilaginous and oppose vertically.
The vertebrate jaw is derived from the most anterior two pharyngeal arches supporting the gills, and usually bears numerous teeth.
The vertebrate jaw probably originally evolved in the Silurian period and appeared in the Placoderm fish which further diversified in the Devonian.
It is believed that the hyoid system suspends the jaw from the brain case of the skull, permitting great mobility of the jaws.
The original selective advantage offered by the jaw may not be related to feeding, but rather to increased respiration efficiency.
The jaws were used in the buccal pump (observable in modern fish and amphibians) that pumps water across the gills of fish or air into the lungs in the case of amphibians.
Over evolutionary time the more familiar use of jaws (to humans), in feeding, was selected for and became a very important function in vertebrates. Many teleost fish have substantially modified jaws for suction feeding and jaw protrusion, resulting in highly complex jaws with dozens of bones involved.
Jaw Suspension or Suspensoria:
The method by which the upper and lower jaws are suspended or attached from the chondrocranium is known as jaw suspension or suspensorium.
Amongst the visceral arches, the first (mandibular) arch consists of
= a dorsal palato pterygoquadrate bar forming the upper jaw,
= and ventral Meckel’s cartilage forms the lower jaw.
The second (hyoid) arch consists of = a dorsal hyomandibular supporting and suspending the jaws with the cranium, and a ventral hyoid.
The remaining visceral arches support the gills and are, hence, called branchial arches. Thus, splanchnocranium forms the jaws and suspends them with the chondrocranium.
INTRODUCTION
The term urogenital refers to something that has both urinary and genital origins. The word urogenital is used because the urinary and reproductive systems in males merge.
These are grouped together because of their proximity to each other, their common embryological origin and the use of common pathways (ex. urethra).
Kidneys and urinary ducts form the urinary system.
The Urinary system performs two important homeostatic processes like excretion and osmoregulation. This system is intimately associated both anatomically, and in terms of embryonic origin with the genital system.
The genital system includes the gonads which generate gametes and the genital ducts that serve as passages for the gametes.
Though functionally different the two organ systems the urinary and the genital system are treated together as the urino- genital system, since both develop from the same segmental blocks of trunk mesoderm or adjacent tissues and share many of the ducts.
Thus although the two systems have nothing common functionally they are closely associated in their use of common ducts and are studied under the broad heading of urinogenital system.
The function of the excretory system is crucial in considering the possible environment of the ‘vertebrate life ’. Several main functions can be attributed to all vertebrate excretory systems:
Excretion of nitrogenous waste products.
Maintaining homeostasis with regard to ions (i.e. salt balance).
Regaining valuable substances (glucose, salts, amino acids, etc.)
Maintaining a physiological osmotic value (i.e. water balance).
The excretory system is formed by a series of paired, segmental nephrons that begin with a nephrostome opening into the coelomic cavity.
A pair of glomeruli per segment, supplied by branches from the aorta, projects into the coelomic cavity close to these nephrostomes.
At a later stage of development, the glomerulus/nephrostome area becomes separated from the rest of the coelomic cavity by an epithelial fold.
The nephrons connect to a duct that is formed by caudal growth of the most anterior nephric tubules. These paired urinary ducts open near the anal region.
The primitive blueprint for the heart and circulatory system emerged with the arrival of the third mesodermal germ layer in bilaterians. Since then, hearts in animals have evolved from a single layered tube to a multiple chambered heart in due course of time.
INTRODUCTION
The jaw (Upper and lower) is any opposable articulated structure at the entrance of the mouth.
It is typically used for grasping and manipulating food.
Jaw suspension means the fusion of upper jaw and lower jaw or skull for efficient biting.
There are different ways in which these attachments are attained depending upon the modifications in visceral arches in vertebrates.
In most vertebrates, the jaws are bony or cartilaginous and oppose vertically.
The vertebrate jaw is derived from the most anterior two pharyngeal arches supporting the gills, and usually bears numerous teeth.
The vertebrate jaw probably originally evolved in the Silurian period and appeared in the Placoderm fish which further diversified in the Devonian.
It is believed that the hyoid system suspends the jaw from the brain case of the skull, permitting great mobility of the jaws.
The original selective advantage offered by the jaw may not be related to feeding, but rather to increased respiration efficiency.
The jaws were used in the buccal pump (observable in modern fish and amphibians) that pumps water across the gills of fish or air into the lungs in the case of amphibians.
Over evolutionary time the more familiar use of jaws (to humans), in feeding, was selected for and became a very important function in vertebrates. Many teleost fish have substantially modified jaws for suction feeding and jaw protrusion, resulting in highly complex jaws with dozens of bones involved.
Jaw Suspension or Suspensoria:
The method by which the upper and lower jaws are suspended or attached from the chondrocranium is known as jaw suspension or suspensorium.
Amongst the visceral arches, the first (mandibular) arch consists of
= a dorsal palato pterygoquadrate bar forming the upper jaw,
= and ventral Meckel’s cartilage forms the lower jaw.
The second (hyoid) arch consists of = a dorsal hyomandibular supporting and suspending the jaws with the cranium, and a ventral hyoid.
The remaining visceral arches support the gills and are, hence, called branchial arches. Thus, splanchnocranium forms the jaws and suspends them with the chondrocranium.
INTRODUCTION
The term urogenital refers to something that has both urinary and genital origins. The word urogenital is used because the urinary and reproductive systems in males merge.
These are grouped together because of their proximity to each other, their common embryological origin and the use of common pathways (ex. urethra).
Kidneys and urinary ducts form the urinary system.
The Urinary system performs two important homeostatic processes like excretion and osmoregulation. This system is intimately associated both anatomically, and in terms of embryonic origin with the genital system.
The genital system includes the gonads which generate gametes and the genital ducts that serve as passages for the gametes.
Though functionally different the two organ systems the urinary and the genital system are treated together as the urino- genital system, since both develop from the same segmental blocks of trunk mesoderm or adjacent tissues and share many of the ducts.
Thus although the two systems have nothing common functionally they are closely associated in their use of common ducts and are studied under the broad heading of urinogenital system.
The function of the excretory system is crucial in considering the possible environment of the ‘vertebrate life ’. Several main functions can be attributed to all vertebrate excretory systems:
Excretion of nitrogenous waste products.
Maintaining homeostasis with regard to ions (i.e. salt balance).
Regaining valuable substances (glucose, salts, amino acids, etc.)
Maintaining a physiological osmotic value (i.e. water balance).
The excretory system is formed by a series of paired, segmental nephrons that begin with a nephrostome opening into the coelomic cavity.
A pair of glomeruli per segment, supplied by branches from the aorta, projects into the coelomic cavity close to these nephrostomes.
At a later stage of development, the glomerulus/nephrostome area becomes separated from the rest of the coelomic cavity by an epithelial fold.
The nephrons connect to a duct that is formed by caudal growth of the most anterior nephric tubules. These paired urinary ducts open near the anal region.
The vertebrate brain
The vertebrate brain is the main part of the central nervous system. The brain and the spinal cord make up the central nervous system,
In most of the vertebrates the brain is at the front, in the head. It is protected by the skull and close to the main sense organs.
Brains are extremely complex and the part of human and animal body. The brain controls the other organs of the body, either by activating muscles or by causing secretion of chemicals such as hormones and neurotransmitters.
Muscular action allows rapid and coordinated responses to changes in the environment.
The brain of an adult human weights about 1300–1400 grams .
In vertebrates, the spinal cord by itself can cause reflex responses as well as simple movement such as swimming or walking. However, sophisticated control of behaviour requires a centralized brain.
The structure of all vertebrate brains is basically the same.
At the same time, during the course of evolution, the vertebrate brain has undergone changes, and become more effective.
In so-called 'lower' animals, most or all of the brain structure is inherited, and therefore their behaviour is mostly instinctive.
In mammals, and especially in man, the brain is developed further during life by learning. This has the benefit of helping them fit better into their environment. The capacity to learn is seen best in the cerebral cortex.
Three principles
The brain and nervous system is essentially a system which makes connections. It has input from sense organs and output to muscles. It is connected in several ways with the endocrine system, which makes hormones, and the digestive system and sex system. Hormones work slowly, so those changes are gradual.
The brain is a kind of department store. It has, all inter-connected, departments which do different things. They all help each other gather senses.
Much of what the body does is not conscious. Basically, much of the body runs on automatic (breathing, heart beat, hungry, hair growth) adjusted by the autonomic nervous system. The brain, too, does much of its work without a person noticing it. The unconscious mind refers to the brain activities which are hardly ever noticed.
Evolutionary change in heart of vertebrates
Heart is situated ventral to the oseophagus in the pericardial section of the coelom.
Heart is a highly muscular pumping organ that pumps blood into arteries and sucks it back through the veins.
In vertebrates it has undergone transformation by twisting from a straight tube to a complex multi-chambered organ.
. There has been an increase in the number of chambers in heart during evolution of vertebrates.
The heart is covered by a transparent protective covering, called pericardium. It is a single layer in fish.
Within pericardium there is a pericardial fluid, protects the heart from the external injury.
The evolution of the heart is based on the separation of oxygenated blood from deoxygenated blood for efficient oxygen transport.
The male and female reproductive systems develop initially embryonically "indifferent", it is the product of the Y chromosome SRY gene that makes the "difference".
♂ - Male ♀ - Female
The reproductive organs are developed from the intermediate mesoderm.
The permanent organs of the adult are preceded by a set of structures which are purely embryonic, and which with the exception of the ducts disappear almost entirely before the end of fetal life.
These embryonic structures are the mesonephric ducts (also known as Wolffian ducts) and the paramesonephric ducts, (also known as Müllerian ducts). The mesonephric duct remains as the duct in males which gives rise to seminal vesical, epididymes and vas deferens, and the paramesonephric duct as that of the female.
Importantly its sex chromosome dependence, late embryonic/fetal differential development, complex morphogenic changes, long time-course, hormonal sensitivity and hormonal influences make it a system prone to many different abnormalities.
Gonads:
Gonads Produce eggs and sperm cells, transport and sustain egg and sperm cells, nurture developing offspring, and produce hormones.
The gonads, ovary or testis, also develop in the intermediate mesoderm.
They originally form as swellings that lie just ventral to the anterior mesonephric kidney.
A mullarian duct also develops in the intermediate mesoderm near the mesonephric duct.
Due to fusion or failure of 1st ridge to differentiate, some vertebrates (agnathans, some female lizards & crocodilians, & most female birds) have a single testis or ovary.
Hormones cause differentiation of early gonads into either testes or ovaries.
As males develop the mesonephric duct makes connection with the testis as the primary sperm conducting duct, and the mullerian duct is lost.
The vertebrate brain
The vertebrate brain is the main part of the central nervous system. The brain and the spinal cord make up the central nervous system,
In most of the vertebrates the brain is at the front, in the head. It is protected by the skull and close to the main sense organs.
Brains are extremely complex and the part of human and animal body. The brain controls the other organs of the body, either by activating muscles or by causing secretion of chemicals such as hormones and neurotransmitters.
Muscular action allows rapid and coordinated responses to changes in the environment.
The brain of an adult human weights about 1300–1400 grams .
In vertebrates, the spinal cord by itself can cause reflex responses as well as simple movement such as swimming or walking. However, sophisticated control of behaviour requires a centralized brain.
The structure of all vertebrate brains is basically the same.
At the same time, during the course of evolution, the vertebrate brain has undergone changes, and become more effective.
In so-called 'lower' animals, most or all of the brain structure is inherited, and therefore their behaviour is mostly instinctive.
In mammals, and especially in man, the brain is developed further during life by learning. This has the benefit of helping them fit better into their environment. The capacity to learn is seen best in the cerebral cortex.
Three principles
The brain and nervous system is essentially a system which makes connections. It has input from sense organs and output to muscles. It is connected in several ways with the endocrine system, which makes hormones, and the digestive system and sex system. Hormones work slowly, so those changes are gradual.
The brain is a kind of department store. It has, all inter-connected, departments which do different things. They all help each other gather senses.
Much of what the body does is not conscious. Basically, much of the body runs on automatic (breathing, heart beat, hungry, hair growth) adjusted by the autonomic nervous system. The brain, too, does much of its work without a person noticing it. The unconscious mind refers to the brain activities which are hardly ever noticed.
Evolutionary change in heart of vertebrates
Heart is situated ventral to the oseophagus in the pericardial section of the coelom.
Heart is a highly muscular pumping organ that pumps blood into arteries and sucks it back through the veins.
In vertebrates it has undergone transformation by twisting from a straight tube to a complex multi-chambered organ.
. There has been an increase in the number of chambers in heart during evolution of vertebrates.
The heart is covered by a transparent protective covering, called pericardium. It is a single layer in fish.
Within pericardium there is a pericardial fluid, protects the heart from the external injury.
The evolution of the heart is based on the separation of oxygenated blood from deoxygenated blood for efficient oxygen transport.
The male and female reproductive systems develop initially embryonically "indifferent", it is the product of the Y chromosome SRY gene that makes the "difference".
♂ - Male ♀ - Female
The reproductive organs are developed from the intermediate mesoderm.
The permanent organs of the adult are preceded by a set of structures which are purely embryonic, and which with the exception of the ducts disappear almost entirely before the end of fetal life.
These embryonic structures are the mesonephric ducts (also known as Wolffian ducts) and the paramesonephric ducts, (also known as Müllerian ducts). The mesonephric duct remains as the duct in males which gives rise to seminal vesical, epididymes and vas deferens, and the paramesonephric duct as that of the female.
Importantly its sex chromosome dependence, late embryonic/fetal differential development, complex morphogenic changes, long time-course, hormonal sensitivity and hormonal influences make it a system prone to many different abnormalities.
Gonads:
Gonads Produce eggs and sperm cells, transport and sustain egg and sperm cells, nurture developing offspring, and produce hormones.
The gonads, ovary or testis, also develop in the intermediate mesoderm.
They originally form as swellings that lie just ventral to the anterior mesonephric kidney.
A mullarian duct also develops in the intermediate mesoderm near the mesonephric duct.
Due to fusion or failure of 1st ridge to differentiate, some vertebrates (agnathans, some female lizards & crocodilians, & most female birds) have a single testis or ovary.
Hormones cause differentiation of early gonads into either testes or ovaries.
As males develop the mesonephric duct makes connection with the testis as the primary sperm conducting duct, and the mullerian duct is lost.
Embryology Course IX - Urogenital SystemRawa Muhsin
This session discusses the development of the urogenital system and includes:
1. Development of the kidneys and ureters
2. Development of the bladder and urethra
3. Development of the gonads and genital ducts
4. Development of the external genitalia
Fertilization: Sperm and the egg—collectively called the gametes—fuse togethe...D. B. S. College Kanpur
The process where the sperm and the egg—collectively called the gametes—fuse to begin the creation of a new individual whose genome is derived from both parents
Fertilization accomplishes
Sex (the combining of genes derived from two parents)
Reproduction (Creation of a new organism)
First function
to transmit genes from parent to offspring
Second function
is to initiate in the egg cytoplasm those reactions that permit development to proceed
Four Major Events
Contact and recognition between sperm and egg. In most cases, this ensures that the sperm and egg are of the same species
Regulation of sperm entry into the egg. Only one sperm nucleus can ultimately unite with the egg nucleus. This is usually accomplished by allowing only one sperm to enter the egg and actively inhibiting any others from entering.
Fusion of the genetic material of sperm and egg
Activation of egg metabolism to start development
The egg activates the sperm metabolism that is essential for fertilization, and the sperm reciprocates by activating the egg metabolism needed for the onset of development
Anton van Leeuwenhoek, the Dutch microscopist who co-discovered sperm in the 1670s, first believed them to be parasitic animals living within the semen (hence the term spermatozoa, meaning "seed animals“)
The behavior of an organism is essentially an expression of the capabilities of its nervous system. While the environment determines the nature of the stimulus, the response involves the body, especially the nervous system of the organism which is genetically determined.
TYPES OF ANIMAL BEHAVIOUR •
Behaviour can be categorized into two main types,
1. Innate or inherent behaviour
2. Learned or acquired behaviour
Innate or inherent behaviour or stereotyped behaviour is inborn or inherent behaviour sequence of activities which is predictable, species specific, genetically controlled and independent of past experience. • Since this is type of behaviour follows a fixed patern (FAP) which is predictable and found in all members of a species it also called stereotyped behaviour.
Characteristics of innate or stereotyped behaviour •
1. Pattern of behaviour is inherited. It is passed on from parents to offsprings, •
2. It is unlearned behaviour •
3. It occurs in all the members of a species hence it is species specific and predictable. •
4. It is not dependent on past experience as it is an inborn response to a stimulus •
5. It takes place in individuals even when kept in isolation away from their fellow members • 6. Innate behaviour has high adaptability and survival value.
Types of innate behaviour
• There are different types of innate or stereotyped behaviour •
1. Taxis • 2. Irritability • 3. Kinesis • 4. Instincts • 5. Reflexes • 6. Motivation
Learned (acquired) behaviour •
Thorpe defined learning as a long lasting adaptive change in behaviour resulting from past experience; hence it is acquired during the life time of an individual. •
Characteristics of learned behaviour •
1. It is acquired during the life of an organism due to constant experience •
2. It is experience dependant and can be modified through experience •
3. Learning is flexible •
4. Learning behaviour differs from individual to individual to individual among the same species hence not species specific •
5. Learned behaviour is certainly not inherited though the ability to learn is almost certainly inherited as it is dependent on the development of the nervous system of the organism which is inherited
6. All organisms from protozoa to humans have the ability to learn atleast to some extend •
7. However learning in humans surpasses all other animals . Almost everything we do has been learned .No other species surpasses the humans in their amount and range of information that is acquired through learning.
Types of learning • 1:Habituation • 2:Imprinting • 3:Classical conditioning • 4:trial and error learning • 5:latent learning • 6:insight • 7:resoning • 8:congintion
The behavior of an organism is essentially an expression of the capabilities of its nervous system. While the environment determines the nature of the stimulus, the response involves the body, especially the nervous system of the organism which is genetically determined.
Innate or inherent behaviour or stereotyped behaviour is inborn or inherent behaviour sequence of activities which is predictable, species specific, genetically controlled and independent of past experience.
Characteristics of innate or stereotyped behaviour •
1. Pattern of behaviour is inherited. It is passed on from parents to offsprings, •
2. It is unlearned behaviour •
3. It occurs in all the members of a species hence it is species specific and predictable. •
4. It is not dependent on past experience as it is an inborn response to a stimulus •
5. It takes place in individuals even when kept in isolation away from their fellow members • 6. Innate behaviour has high adaptability and survival value.
Types of innate behaviour
• There are different types of innate or stereotyped behaviour •
1. Taxis • 2. Irritability • 3. Kinesis • 4. Instincts • 5. Reflexes • 6. Motivation
Thorpe defined learning as a long lasting adaptive change in behaviour resulting from past experience; hence it is acquired during the life time of an individual.
Characteristics of learned behaviour •
1. It is acquired during the life of an organism due to constant experience •
2. It is experience dependant and can be modified through experience •
3. Learning is flexible •
4. Learning behaviour differs from individual to individual to individual among the same species hence not species specific •
5. Learned behaviour is certainly not inherited though the ability to learn is almost certainly inherited as it is dependent on the development of the nervous system of the organism which is inherited
6. All organisms from protozoa to humans have the ability to learn atleast to some extend •
7. However learning in humans surpasses all other animals . Almost everything we do has been learned .No other species surpasses the humans in their amount and range of information that is acquired through learning.
Types of learning • 1:Habituation • 2:Imprinting • 3:Classical conditioning • 4:trial and error learning • 5:latent learning • 6:insight • 7:resoning • 8:congintion
The urinary system includes the kidneys and the ducts that carry away their product, urine. The genital system includes the gonads and their ducts that carry away the products they form, sperm or eggs. Embryologically, urinary and reproductive organs arise from the same or
adjacent tissues and maintain close anatomical association
throughout the organism’s life.
Immunity can be defined as a complex biological system endowed with the capacity to recognize and tolerate whatever belongs to the self, and to recognize and reject what is foreign (non-self).
Circadian rhythms exhibit a period of about 24 h whereas circannual (seasonal) rhythms cycle over the course of a year. Both types of rhythms are coordinated by the brain's suprachiasmatic nucleus (SCN).
Animal behaviour includes all the ways animals interact with other organisms and the physical environment. It is defined as a change in the activity of an organism in response to a stimulus.
Palestine last event orientationfvgnh .pptxRaedMohamed3
An EFL lesson about the current events in Palestine. It is intended to be for intermediate students who wish to increase their listening skills through a short lesson in power point.
The French Revolution, which began in 1789, was a period of radical social and political upheaval in France. It marked the decline of absolute monarchies, the rise of secular and democratic republics, and the eventual rise of Napoleon Bonaparte. This revolutionary period is crucial in understanding the transition from feudalism to modernity in Europe.
For more information, visit-www.vavaclasses.com
Embracing GenAI - A Strategic ImperativePeter Windle
Artificial Intelligence (AI) technologies such as Generative AI, Image Generators and Large Language Models have had a dramatic impact on teaching, learning and assessment over the past 18 months. The most immediate threat AI posed was to Academic Integrity with Higher Education Institutes (HEIs) focusing their efforts on combating the use of GenAI in assessment. Guidelines were developed for staff and students, policies put in place too. Innovative educators have forged paths in the use of Generative AI for teaching, learning and assessments leading to pockets of transformation springing up across HEIs, often with little or no top-down guidance, support or direction.
This Gasta posits a strategic approach to integrating AI into HEIs to prepare staff, students and the curriculum for an evolving world and workplace. We will highlight the advantages of working with these technologies beyond the realm of teaching, learning and assessment by considering prompt engineering skills, industry impact, curriculum changes, and the need for staff upskilling. In contrast, not engaging strategically with Generative AI poses risks, including falling behind peers, missed opportunities and failing to ensure our graduates remain employable. The rapid evolution of AI technologies necessitates a proactive and strategic approach if we are to remain relevant.
June 3, 2024 Anti-Semitism Letter Sent to MIT President Kornbluth and MIT Cor...Levi Shapiro
Letter from the Congress of the United States regarding Anti-Semitism sent June 3rd to MIT President Sally Kornbluth, MIT Corp Chair, Mark Gorenberg
Dear Dr. Kornbluth and Mr. Gorenberg,
The US House of Representatives is deeply concerned by ongoing and pervasive acts of antisemitic
harassment and intimidation at the Massachusetts Institute of Technology (MIT). Failing to act decisively to ensure a safe learning environment for all students would be a grave dereliction of your responsibilities as President of MIT and Chair of the MIT Corporation.
This Congress will not stand idly by and allow an environment hostile to Jewish students to persist. The House believes that your institution is in violation of Title VI of the Civil Rights Act, and the inability or
unwillingness to rectify this violation through action requires accountability.
Postsecondary education is a unique opportunity for students to learn and have their ideas and beliefs challenged. However, universities receiving hundreds of millions of federal funds annually have denied
students that opportunity and have been hijacked to become venues for the promotion of terrorism, antisemitic harassment and intimidation, unlawful encampments, and in some cases, assaults and riots.
The House of Representatives will not countenance the use of federal funds to indoctrinate students into hateful, antisemitic, anti-American supporters of terrorism. Investigations into campus antisemitism by the Committee on Education and the Workforce and the Committee on Ways and Means have been expanded into a Congress-wide probe across all relevant jurisdictions to address this national crisis. The undersigned Committees will conduct oversight into the use of federal funds at MIT and its learning environment under authorities granted to each Committee.
• The Committee on Education and the Workforce has been investigating your institution since December 7, 2023. The Committee has broad jurisdiction over postsecondary education, including its compliance with Title VI of the Civil Rights Act, campus safety concerns over disruptions to the learning environment, and the awarding of federal student aid under the Higher Education Act.
• The Committee on Oversight and Accountability is investigating the sources of funding and other support flowing to groups espousing pro-Hamas propaganda and engaged in antisemitic harassment and intimidation of students. The Committee on Oversight and Accountability is the principal oversight committee of the US House of Representatives and has broad authority to investigate “any matter” at “any time” under House Rule X.
• The Committee on Ways and Means has been investigating several universities since November 15, 2023, when the Committee held a hearing entitled From Ivory Towers to Dark Corners: Investigating the Nexus Between Antisemitism, Tax-Exempt Universities, and Terror Financing. The Committee followed the hearing with letters to those institutions on January 10, 202
Read| The latest issue of The Challenger is here! We are thrilled to announce that our school paper has qualified for the NATIONAL SCHOOLS PRESS CONFERENCE (NSPC) 2024. Thank you for your unwavering support and trust. Dive into the stories that made us stand out!
Unit 8 - Information and Communication Technology (Paper I).pdfThiyagu K
This slides describes the basic concepts of ICT, basics of Email, Emerging Technology and Digital Initiatives in Education. This presentations aligns with the UGC Paper I syllabus.
Francesca Gottschalk - How can education support child empowerment.pptxEduSkills OECD
Francesca Gottschalk from the OECD’s Centre for Educational Research and Innovation presents at the Ask an Expert Webinar: How can education support child empowerment?
How to Make a Field invisible in Odoo 17Celine George
It is possible to hide or invisible some fields in odoo. Commonly using “invisible” attribute in the field definition to invisible the fields. This slide will show how to make a field invisible in odoo 17.
1. Succession of Kidneys
and
Evolution of Urino-
Genital Ducts
Dr. Manju Bhaskar
Assistant Professor
Department of Zoology
D. B. S. College Govind Nagar C
Block
Kanpur Uttar Pradesh
India
2. Kidneys are built in accordance with a
basic pattern consist of glomeruli, renal
tubule and a pair longitudinal duct.
3. • Larval fishes
• Earliest vertebrate kidneys probably extended the
entire length of the body cavity and had external
glomeruli that drained the coelomic fluid.
4. Basic Components of
Craniate Kidney
• External Glomeruli : most primitive glomeruli are
suspended in the coelom surrounded by coelomic fluid,
which swept into peritoneal funnel, nephrostome.
eg embryos and larvae.
• Internal Glomeruli : glomeruli in adults are embedded
in the dorsal body wall and ensheathed by Bowman’s
capsule, the capsular cavity collects the glomerular
filtrate which passes into renal tubule.
5.
6. Renal tubule originates from embryonic
nephrogenic mesoderm, lies lateral to
mesodermal somites and extends the length of
embryonic trunk from behind the head to cloaca
7. Pronephros
The earliest embryonic tubules arise from the cephalic end
of nephrogenic mesoderm.
Tubules are segmental, one pair at each segment.
In anamniotes they have association with external
glomerulus.
No of pronephric tubules : 3 in larval frog, 7 in human
embryos, 12 in chicks.
The distal end of first several pronephric tubule unite end to
end and establishes an opening into cloaca. This is
pronephric duct.
8. Pronephric tubules are temporary, they loose
their connection with dorsal aorta and regress.
Pronephric duct does not regress.
Although pronephric tubules develop in all
craniates, they function only in embryonic ray
finned fishes and in larval agnathans,
and amphibians.
In amniote embryos they are vestigial or lost.
9.
10. Mesonephros
Pronephric duct act as inductor, additional tubules
develop in nephrogenic mesoderm behind the
pronephric region and establish an entrance into the
existing pronephric duct.
Fishes, amphibian and nonavian reptiles have open
nephrostome that usually close later in development.
Mesonephros become functional throughout life in
fishes and amphibians.
Functional embryonic kidney of amniotes.
11. Some of the anterior mesonephros tubules in male
fishes and amphibians become utilized to transport
sperm from the testis to mesonephric duct via substance
of kidney.
Mesonephric tubules are vasa efferentia.
The region of adult male kidney is preempted for sperm
transport and known as sexual kidney, coiled part of
mesonephric duct is known as epididymis.
Accessory urinary duct supplement or even replace
mesonephric duct as carrier of urine.
12. During mesonephros establishment, when last
mesonephric tubules formed, earliest tubules already
regressed. 15.12
During the time of mesonephros functioning, a new
kidney metanephros is organizing, when metanephros is
able to function, mesonephros regresses.
13.
14.
15. Metanephros
Metanephros organizes from the caudal end of nephrogenic
mesoderm which becomes displaced cephalad and laterad during
development.
Differentiation of metanephric kidney commences when a hollow
metanephric bud sprouts from the caudal end of the mesonephric
duct.
The hollow stalk connecting the metanephros with embryonic
mesonephric duct becomes ureter.
Urinary channels form within the kidney and open into common
collecting tubules.
Meanwhile ‘S’ shaped renal tubules grows and encapsulates
glomerulus to form renal corpuscle and other end form collecting
tubule.
Renal pelvis collects urine from common collecting tubules.
20. Reproductive Organs
The reproductive system includes the gonads, their
products, hormones and gametes, and the ducts that
transport gametes.
Gonads have two major functions :
Produce gametes
Synthesize steroidal hormones
Hormones requires for differentiation, growth and
maintenance of accessory sex organs (reproductive
ducts and their glands), secondary sex characteristics.
21. Gonads arise as genital ridge
Thickening in the splanchnic mesoderm
Indifferent gonad
Gonads of both sex contain germ cells (sperm or ova)
In females germ cells resides in cortex
In males germ cells resides in medulla
22. Testes and Male Genital Ducts
Germinal epithelium lines the seminiferous tubules
where sperms are formed.
Vasa efferentia are mesonephric tubules which conduct
sperm to spermatic duct.
In most craniates with mesonephric ducts carry both
sperm and urine.
Hagfishes, lampreys, some jawed fishes and urodeles
lack seminiferous tubules.
Germinal epithelium may be on the surface of the testis
or deep within and primordial germ cells migrate into
cyst like seminiferous ampullae.
After breeding season cyst collapse.
23. In some fishes, a new sperm duct replace the
mesonephric duct as a carrier of sperm, marginal
canal.
Other fishes, amphibians, reptiles to humans, the
embryonic mesonephric duct remains in adult males
to carry sperm known as vas deferens.
27. Female genital tract consist of paired muscular and
glandular oviducts that commence at an ostium, open to
coelom, leads to neck to oviducal funnel.
Oviducts end in cloaca or a subdivision of it.
Any differences along the length of the tract are in the
degree of regional specializations that support species
specific functions such as collecting egg from coelom,
coating them with protective or nutrient substances,
temporarily housing eggs, embryos or larvae and
maintaining them until the eggs are shed or young are
delivered.
In craniates other than ray finned fishes, the female duct
system differentiates from a pair of embryonic Muellerian
duct.
28. Cyclostomes ovary lack oviducts, eggs are shed into
coelom
From coelom ova reach to cloaca (lamprey) or anus
(hagfish) through secondary pores
In elasmobranchs ovaries are initially paired, but in
some only one may develop
29. Muellerian duct develop in both, but do not perisist in
males.
The Muellerian duct of Elasmobranchs and Amphibians
arise by longitudinal splitting of the pronephric duct and
their ostia develop from one or several pronephric
nephrostomes.
In other craniates, each Muellerian duct arise as
longitudinal groove in the coelomic epithelium parallel to
mesonephric duct, which becomes tube like structure.
30. • The Mullerian duct or oviduct has 4 regions
Funnel : it collects eggs shed from the ovary, anterior end of
paired oviducts may fuse into single funnel
Shell gland : it stores sperm in most elasmobranchs,
secretes albumen and mucus.
• In oviparous species, the shell gland produces the egg case as well.
• In viviparous species, may be indistinguishable.
Isthmus : it connects shell gland to uterus.
Uterus : Nutritionally supports embryos.
• Oviducts may join before they enter the cloaca, or they may enter
separately.
• The genital ducts of chimaeras are similar to those of sharks, except
the oviducts always share a common funnel and each oviduct opens
separately into the cloaca.
31. The Muellerian
duct of female
sharks’s give
rise to an
oviduct that
develops a
shell gland
and uterus
32.
33.
34. The lining of amphibian oviduct are richly supplied with
glands that secrete several layers of protective jelly envelops
around each egg as it moves down the tube.
Female tract of reptiles and monotremes mammals conform
closely to the basic pattern.
only one of the two embryonic Muellerian duct may
differentiate (crocodile and most birds).
Albumen gland line part of the oviduct and usually a shell
gland anterior to cloaca.
Albumen secreting area in fowl is known as magnum, shell
gland is a uterus and short glandular and muscular
at the base of entrance to the cloaca is vagina
35. Therian mammals
In other craniates, paired muellerian ducts in mammals
give rise to female genital tract commencing with the
ostium of the oviduct.
Muellerian duct of eutherian mammals unite at their
caudal ends to one degree or another.
The tract of eutherian mammals consist of two oviducts,
a uterus with or without horns (cornu) and a vagina.
Oviducts are short and small in diameter (microlecithal
egg), more or less convulated.
Oviducal funnel has a fringed border.
36. In some teleosts, such as salmonids, eggs released
from the ovaries fill the body cavity. Eventually they
reach short, funnel-like remnants of the oviducts
situated at the posterior part of the coelom. However,
in many teleosts, the oviducts regress entirely, leaving
egg transport to new ovarian ducts
Most teleost fishes lay eggs, but some bear live
young. Among these viviparous teleosts, maternal
tissues may nourish the embryo
37. Tetrapod
Amphibian ovaries are paired, hollow structures that
usually show a prominent cortex covered by germinal
epithelium. The genital ducts of female amphibians are
usually simple and consistent. The archinephric ducts
serve the Opisthonephric kidneys; the oviducts
(Müllerian ducts) serve the ovaries.
38. Amniotes
In amniotes, remnants of the mesonephros may persist in
larval stages, but adults have metanephric kidneys drained
exclusively by new paired ducts, the ureters (metanephric
ducts).
In females, the archinephric ducts are rudimentary. The
oviducts (Müllerian ducts) persist in their roles of transporting
ova from the ovaries and supporting the embryo while it is in
transit.
The tubular oviducts (Müllerian ducts) of amniotes often have
prominent sheets of smooth muscle within their walls and a
lumen lined by a secretory mucosa.
In oviparous amniotes, a shell gland may be prominent; in
viviparous amniotes the uterus may be distinct
39. Uterus
The uterus is the terminal portion of the oviduct.
Shelled eggs waiting to be laid or embryos completing their
development are held within the uterus.
In eutherian mammals and a few other vertebrates, the walls
of the uterus and extraembryonic membranes of the embryo
establish a close vascular association through a placenta.
Nutrients and oxygen are transported to the developing
embryo, and carbon dioxide is given up to the maternal
circulation via the placenta.
40. Uteri : Four types
Duplex : The muellerian duct of marsupials are paired
all the way to urino-genital sinus (subdivision of claoca).
Marsupials have two completely separate uteri and two
vagina. Eg. Kangaroos
Bipartite : a uterus with two horns may have totally
separate passageways within the body of the uterus, but
share a single cervix. Eg ruminants, cats horses.
Bicornuate : the uteri of eutherian mammals exhibit
varying degree of fusion distally (no partition in fused
portion, middle to post. part fused) eg. Dogs, pigs,
elephants, whale
Simplex : maximum fusion occurs in muellerian duct, in
which fusion commences at the ends of short oviduct
and there are no uterine horns eg primates (human )
41. Bicornuate : the uteri of eutherian mammals exhibit
varying degree of fusion distally (no partition in fused
portion, middle to post. part fused) eg. Dogs, pigs,
elephants, whale
Simplex : maximum fusion occurs in muellerian duct,
in which fusion commences at the ends of short
and there are no uterine horns eg primates (human )