Frogs

It is universally accepted that amphibians (frogs) have originated from fishes. Resemblance of amphibia to fish is seen in most systems of the body. Both are cold blooded. Fish respire by gills and also tadpole of frog respires by gills. To prevent dessication in air, both usually lay eggs in water.

In male frog the sperms will move from Testes Vasa efferentia Kidney Bidder's canal Urinogenital duct Cloaca.

In frogs, the vena cava is the blood vessel that carries deoxygenated blood from the body back to the heart. The vena cava collects blood from the body tissues and delivers it to the right atrium of the heart, where it is then pumped to the lungs for oxygenation. Thus, the correct answer is Vena cava.

In male frogs, the copulatory pad is located on the first digit of the fore limb. This pad is used during mating to grasp the female frog and maintain a secure position while the female lays her eggs. Thus, the correct answer is First digit of the fore limb.