Animal Reproductive system Slides Flashcards
Reproductive Systems
In vertebrates, develop in concert with urinary system
Components: Gonads and Genital Ducts
Functions: Meiosis and gamete formation
Embryo support
Endocrine
Hormone effects: Sex differentiation
System operation
Reproductive readiness
Testis (Testicle in mammals)
Sac filled with Seminiferous Tubules
Seminiferous Tubules:
Sites of meiosis
Continuous with Spermatic Duct (Vas Deferens)
Contain Sertoli Cells: support/nourish sperm
Outside Tubules: Interstitial cells secrete Testosterone
Spermatic Duct
Includes Epididymis in Amniotes Sperm storage compartment Includes glands to make seminal fluid e.g. mammal Prostate Seminal fluid nourishes and protects sperm
Ovary
Individual eggs develop within Follicles
Follicle: fluid filled cavity
Each follicle contains one egg and follicular cells
Follicular cells secrete Estrogen
Ovulation: mature follicle ruptures to release egg
Captured by Fallopian Tube
Some derivatives of the
Oviduct
Glands to produce eggshells/protective jelly
Sperm storage areas/organs e.g. Spermatheca
Uterus for embryo development
Oviparous
egg laying Universal in birds Found in all vertebrate classes Rarest in sharks and mammals Egg laying mammals: Monotremes e.g. Platypus
Birth styles
Ovoviparous: Live birth
Embryos develop in uterus; sustained by yolk alone
Some reptiles and sharks
Viviparous: Live birth
Embryos sustained by non yolk maternal support
e.g. Placenta in mammals and some sharks
Placenta: membranes separate maternal and
embryonic blood; allow factor exchange
Modes of Fertilization
External and Internal
External Internal
Aquatics only Terrestrial or to economize
Most bony fishes on gametes e.g. sharks
Most frogs Fewer gametes produced
Wasteful of gametes; More parental care
lots of gametes produced
Little parental care
In external fertilization, gamete loss minimized by nesting in
fishes and amplexus in frogs
3 methods of Internal fertilization
Cloaca juxtapositioning e.g. birds
Cloaca: body opening for urine, feces and gamete release
Spermatophore: packet of sperm deposited by male; taken in
by female e.g. salamanders
Intromittent organ: male appendage to deliver sperm into
female body e.g. penis