310 likes | 657 Views
Excretory & Reproductive Anatomy. Excretory & Reproductive - Close anatomical ties. Typical vertebrate arrangement Excretory and reproductive anatomy closely tied May share common ductwork in some individuals. Excretory/Reproductive Systems. General locations. Kidneys.
E N D
Excretory & Reproductive- Close anatomical ties • Typical vertebrate arrangement • Excretory and reproductive anatomy closely tied • May share common ductwork in some individuals
Excretory/Reproductive Systems • Systems lie in close proximity to one another within body cavity
Excretory System • Pronephros - functional in adult hagfish, fish embryos
Excretory System • Mesonephros - portion of functional kidney in adult fish
Fish kidneys • Diffuse organs on either side of vertebral column • Varying degree of connection with reproductive system • Little connection in most advanced fishes
Shark kidney • Sharks and relatives have close ties between kidneys and testes • Share ductwork
Kidneys and urinary bladder • Some fish have a urinary bladder • Located at end of ureter(s) • More often present in male fish
Hagfishes • Monoecious - all individuals have capacity to be either male or female • Single gonad can develop into testis or ovary • Can it switch or be both at same time?
Hagfish ovary • Produces few, large eggs • 1 or 2, or up to 30, depending on species
Hagfish ovary • Eggs get dumped into body cavity before exiting body • Internal/self fertilization?
Lamprey ovary or testis • Lampreys are male or female • Single ovary or testis • Reproductive products dumped into body cavity before exiting (no ductwork)
Class Chondrichthyes • Sexes separate and fertilization internal • Oviparous, ovoviviparous, viviparous
Shark testes • Paired testes • Located near anterior end of body cavity
Ductwork • Ducts convey sperm to storage area • Stored until copulation
External sex characteristics • Pelvic claspers in males • Aid in sperm transfer to female • Female with simple cloacal opening
Other characteristics • Male sharks, chimaeras may have head clasper as well as well as pelvic clasper • Not used in sperm transfer
Bony fishes • Most bony fish are dioecious (male and female) • Gender differences not always very apparent • Tubercles may develop in males
Bony fishes • Others may develop vivid colors • Males boldly marked • Many minnows, darters
Bony fishes • Fertilization is usually external (oviparous) • Female ejects eggs, male ejects sperm (milt)