PRESENTED BY:FATIMA KHARBE

URINOGENITAL SYSTEM

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o URINARY SYSTEM OF VERTEBRATES INCLUDE KIDNEYS AND THEIR DUCTS.

• REPRODUCTIVE SYSTEM INCLUDES MALE AND FEMALE

GONADS AND THEIR DUCTS.

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• THE 2 SYSTEMS ARE INTIMATELY RELATED MORPHOLOGICALLY IN VERTEBRATES HENCE THE TWO SYSTEM ARE AS DESCRIBED AS UROGENITAL OR URINOGENITAL SYSTEM

BASIC STRUCTURE OF EMBRYONIC KIDNEY

Pair of compact organs lying on

either side of dorsal aorta.

Each kidney is composed of large no of units called as URINIFEROUS TUBULES OR NEPHRONS.

Kidney tubules arise in the embryo in a linear series from mesoderm. Each uriniferous tubule is differentiated into 3 parts. 1.PERITONEAL FUNNEL

2.MALPIGHIAN BODY

3.TUBULE

Urinary System - Kidneys

Kidneys are pair of compact organs lying on either

Side of dorsal aorta.

Evolution of kidney takes place

as: ARCHINEPHROS PRONEPHROS MESONEPHROS METANEPHROS

ARCHINEPHROS

Excretory organ of ancestral vertebrates.

Also called as HOLONEPHROS 0r complete kidney as it runs throughout the entire length of coelom.

Composed of pair of archinephric ducts.

Each duct has a pair of tubules to a

segment.

Each tubule is opened by a nephrostome in coelom.

Near each nephrostome there is an external

glomerulus.

All tubules are drained into duct Which opens in cloaca.

Archinephros

• Larvae of caecilians and Hagfish have this type of excretory system.

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⚫Tissue fluid discharge from

glomerulus<<coelom<<

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⚫Nephrostome<<tubules<<

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⚫Archinepric ducts<<cloaca.

PRONEPHROS

• 1 Embryonic tubule to appear hence called as pronephros.
• Also called as head kidney.
• Composed of pronephric ducts.
• Consist of 3 to 15 tubules segmentally arranged,
• Each tubules open into coelom by nephrostome.
• Also projecting into coelom there is an external glomerulus.
• In some cases glomeruli unite to form glomus.

PRONEPHROS

• All tubules of pronephros open into the pronephric duct.
• Which opens into cloaca..
• Pronephros is functional only in embryonic or larval stage,and it is soon replaced by mesonephros.
• Pronephros is retained throughout life in adult cyclostomes and teleost fishes.
• Filtrate of blood through glomerulus<<coelom<<nephrost ome<<
• Tubule<<pronephric

duct<<cloaca.

MESONEPHROS

• Develops from middle part of

intermediate mesoderm.

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• Form soon after degradation of pronephros.
• Mesonephros is functionally

better than pronephros

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• bcoz mesonephric tubules are numerous in number.
• They develop internal

glomeruli.

MESONEPHROS

• They are also termed as

wolffian body.

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• Mesonephros is functional only in embryos in amniotes.

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• In sharks n caecilians tubules

extend posteriorly

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• Throughout coelom such

kidney is called as

OPISTHONEPHROS.

Mesonephros

• Soon with the degradation of pronephros the pronephric duct forms the wolfian or mesonephric duct.

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• In amniotes mesonephros is functional only in the embryos and replaced by metanephros in adults

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• Nephrpstomes are generally lacking in embryonic amniotes.

METANEPHROS

• Arise posterior to the mesonephros.
• It’s the functional kidney of higher

vertebrates or amniotes.

• it is formed from the posterior end of the nephrogenic mesoderm.
• When all metanephric tubules develop all

mesonephric ducts disappear except those

• Associated with testis in male forming vasa efferentia.
• It shows greater multiplication and

concentration of nephrons.

• It s functional unit is nephron.

METANEPHROS

Renal Cortex: Renal corpuscle Convoluted tubules Renal Medulla: Collecting ducts Loop of Henle

Each Minor calyx drains a tree of collecting ducts

within a renal pyramid

Pyramids are separated by columns of cortical tissues called renal columns

The Renal pyramids

Nephron

• The tubules differentiates into the
• 1) Bowman’s capsule
• 2) Proximal convoluted tubule
• 3) Loop of Henle
• 4) Distal convoluted tubule
• The distal convuluted tubule fuses with the collecting duct Renal corpuscle = Bowman’s capsule/glomerulus. The nephron is
• the metanephric excretory unit.
• The origin of the Renal corpuscle and tubules is distinct from the
• collecting duct (Metanephric duct)
• Duct systems merge
• Renal duct – sequence of differentiation
• renal corpuscle proximal tubule distal tubule
• Loop of Henle elongates into the medulla

COMPARATIVE ANATO:MY OF THE METANEPHROS

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Reptiles

⁰ Kidneys restricted to the posterior half of the abdominal cavity and confined to the pelvic region.

⁰ Generally small and

compact, with

lobulated surface.

Bladder

Urogetlltal -

papilla

Urogenital system of female spheno'

Birds

⁰Kidney located in the pelvic region of the body cavity with the posterior end u ually united.

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⁰ Lobed structure with hort ureters which open into the cloaca.

Maebird's urogenitalsystem

URINARY BLADDER

Urinary bladder

Most vertebrates have urinary bladder to store urine before it is discharged.

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FISHES: enlargement of mesonephric ducts called

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TUBAL BLADDER.

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AMPHIBIANS: termed as CLOACAL BLADDER.

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AMNIOTES: ATLONTOC BLADDER

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Mammals lack cloaca hence the kidney ducts or ureter lead directly into the urinary bladder which opens into URETHRA

GENITAL SYSTEM

• Vertebrates exhibit sexual reproduction.

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• Sexes are separate with exception of few hagfishes and few bony fishes.

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• Male gonads…..Testes ….. produces sperms

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• Female gonads …..Ovaries ….produces ova

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• Gonads originate as a pair of genital ridges.

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• Generally 1 pair of gonad are present but some vertebrates have single gonad.

TESTES AND MALE GENITAL DUCTS.

• TESTES: Seminiferous

tubules: sperm factory

• Produces sperm
• Mature spermatozoa will

move to rete testis

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• Then to efferent dutules<<epididymis<<vas deferens<<urethra.
• Testes also act as an endocrine

gland produces teststerone.

"Lt\LE GE ITAL D T

o orne fishe (e.g., ar

& turgeon) &

amphibians ·

me oneplu·ic duct

tran mit perm &

.

unne

o orne amphibian · mesonephric duct tran"port only

perm: new acee ory urinary due drain the kidnev_.,

MALE GENITAL DUCTS

Testis j

Opistho­

nephros

Mesonephric

duct

Eff. r:-

- ductule

1

1

.

.. .-Wolffian duct

;.:lt;: drfHHI!)

_{,-------._.} o Sharks - mesonephric

duct is used primarily

for sperm transport; accessory urinary duct develops

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o Teleosts­ mesonephric duct drains kidney; separate sperm duct develops

o Amniotes - embryonic mesonephric ducts transport sperm in adults

Agnathans

Gar Sharks Amphibi ans Amn ioU

Sturgeon

IMale Urogenital RelationsJ

OVARIES

Ovaries are found in pairs except in some cyclostomes and teleosts.

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Ovary shows layer of germinal epithelium showing ova in various stages of development.

Mature eggs are releasesd in the

oviduct .

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This process is termed as OVULATION.

OV DUCTS

o Modifications of the Mullerian ducts, which degenerates in the males.

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o Differentiates into regi^• ons.

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o Posterior portion expands

to become the uterus.

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o Serves as temporary storage site for eggs or a place where the young develops.

OVARY :REPTILE

o Plll.red or (115

o Only the righl ot-ary {ufl)

d tdo and the lt>ft

d nerat in m

ela:-mobrnnch .

o Most Ieos ·han-

ucculor type O\'lrie

which produce large

numlx>r or0\"8 during the

br in n .

• Ripe 0\11··>c ntral or.mon

m1tv-->oridart ->out id.!

•.\tluh td ,t bck d

andh:n pantt>c

Crom uruwy and di. m­

.., til:

OV RY:AMI HIBL

o accular

o Ova escape into the coelom through their external walls.

o hape varie with

the shape of the

o nakes and lizards' O\'aries are "accular and elongated .

oTurtles and crocodilians have solid ovaries.

o Certain OVOVIVIparous snakes and lizards have corpora 1utea that form from ruptured follicle" after ovulation.

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t..!V U lJ\LLtV OVARIES

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o L<lcated inthe lumbar or pelvic region.

o Considered small in relat ion to the size of the body of mammals.

o Placental mammals have compact oYaries with an antrum within the graafia.n follicles.

o Co\·ered by germinal epithelium from which oocrtes arise.

o orne of this oocytes become mature ova during the life of the individual.

body.

o Fat bodt e nre clo ely a octnted with the ovane

o Both ovaries are present in embryonic development .

o In most birds. the right ovary degenerates. and the left becomes the functional gonad.

o Stigma or cicatrix is a band located on the surface of the follicle

through which mature liialbl

ova escape from the al

ovarian follicles into the coelom .

In the absence of testosterone:

The mesonephric duct degenerates

The Mullerian duct develops uninhibited

Mullerian duct - cranial funnel-shaped opening to

the

coelom forms the fimbriare of the infundibulum The cranial Mullerian duct forms the uterine tubes The caudal end of the Mullerian ducts fuse to form the

uterovaginal canal that later forms the uterus and the superior vagina

nt organs:

• useful when fertilization is internal; introduce sperm into female reproductive tract
• found in some fish, some birds, reptiles, & mammals
• cartilaginous fish - appendages of pelvic fins called claspers direct sperm into female reproductive tract

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• snakes & lizards - have pair of HEMIPENES

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• turtles, crocodilians, a few birds, & mammals - exhibit an unpaired erectile penis
• penis - usually a thickening of floor of cloaca consisting of spongy erectile tissue (corpus spongiosum) with grooves to direct sperm & ending in a glans penis (sensory endings that reflexly stimulate ejaculation)

GOT BORE??