Different reproductive organs in vertebrates
REPRODUCTIVE SYSTEM IN FISHES AND AMPHIBAN
(MALE AND FEMALE REPRODUCTIVE SYSTEM)
MALE REPRODUCTIVE SYSTEM
Male have two testes. In many fishes in amphibians, each testis is joined by fine tubes (vasa efferentia) to sperm conducting tubule in the anterior part of the kidney. The kidney tubule together with other urine-conducting kidney tubules drain into a common duct called the wolffian duct. This duct transport both urine and sperms and open into the cloaca in some frog and toads each wolffian duct enlarges near its posterior region to form a sac. The seminal vesicle, where sperms are stored.
FEMALE REPRODUCTIVE SYSTEM
Female usually have two ovaries which produce egg cells with a small amount of yolk. These are discharged into the body cavity and are pushed into the oviduct. The oviducts open into the cloaca. As the eggs travel along the oviducts they become coated with albumen produced by the glands. In frog and toad, the oviducts enlarge to form thin walls sac called ovisac.
REPTILES AND BIRDS
Male Reproductive system
Male have a part of testes near the kidneys a sperm duct from each testis leads to the cloaca in reptiles, the sperm duct enters the cloaca and join the penis. The penis is used to eject sperms into the female reproductive tract during ovulation. Lizards and snakes have two copulatory structures called hemipenes.
Birds do not have penis. In many birds the sperm duct expands at their posterior end to form seminal vesicle, sperm accumulate here.
During copulation sperms are transferred from the male to the female when their cloaca come in contract.
FEMALE REPRODUCTIVE SYSTEM (REPTILES AND BIRDS)
Reptile have paired ovaries and oviducts. The oviducts open externally into the body cavity and lead posteriorly to open again into the cloaca in birds there is only one ovary and oviduct. The ovules of reptiles and birds produce eggs cells with large yolk. These are discharged into the body cavity. from there they enter the oviduct fertilization occurs in the oviduct the eggs are covered with albumen shell membranes and shells.