CVA: UROGENITAL

Reproductive sys adapted for producing

viable offspring

Kidneys

principal organ of urinary sys

Kidneys forms

w/in mesoderm of dorsal body wall

Vert. kidneys develop in

3 stages

anterior stage

middle

mesonephros

posterior

metanophros

Mesonephros

Replaces pronephros;

Functional in embryos, replaced in amniotes;

Joins with posterior tubules to form opisthonephros;

Drains via mesonephric (archinephric) duct

Metanephros

Develops LAST;

Adult kidney in all amniotes;

Drains via ureter (metanephric duct), not archinephric duct

Nephron

functional unit of kidney

METANEPHRIC tubules form well-differentiated

nephrons

Fluid filtered form blood at glomerulus, enters

nephron

Loop of Henle

Elongated part of nephron that uses countercurrent exchange to concentrate urine, conserve water

Parts of embryonic urinary tract are utilized by

reproductive tract

Uterus

Terminal portion of oviduct (aka Fallopian tubes);

Holds shelled eggs waiting to be laid; developing embryos

Therian mammals

oviducts merge into a 1x uterus (usually) and vagina

Eutherian mammals

placenta forms vascular connection w embryo

Testes are paired EXCEPT in

cyclostomes and some teleosts

Testes are suspended from dorsal body wall by

mesorchrium (mesentery)

Fish and amphibs produce sperm from

clones of spermatogonia (spermatocyst)

In amniotes, spermatogonia

remain in seminiferous tubules (1 form each mitotic pair)

Fertilization MUST be int. if (before oviduct)

uterus holds embryo or egg is sealed by shell

Copulation (coitus)

Apposition of female and male cloacae to transfer sperm

Frogs fertilize usually

externally

Salamanders fertilize via

males depositing sperm in spermatophore, gathered by female

Penis is probably derived from

cloaca

Penis erection for copulation through

hemotumescense (blood infiltraiton)

Penis are parried with corpora cavernosa which

hold blood to form erection

Crocs and turtles have a 1x grooved penis formed from

cloaca

In birds, sperm travel through

solucus spermaticus (groove)

For turkeys, simple swelling @

cloaca edges

Baculum

“penis bone” function: erectile aid

Duplex

oviducts join vagina

Bipartite

uterus divided

Bicornuate

uterus partially divided into

Simplex

uterus single and undivided