Chordata
The chordate life cycle begins with fertilization (the union of sperm and egg). In its primitive form, fertilization occurs externally, in the water. Asexual reproduction takes place in tunicates and in some vertebrates (females of some fish and lizards can reproduce without fertilization). Hermaphroditism (possessing both male and female reproductive organs) is found in tunicates and some fishes, but otherwise the sexes are separate. Larvae (very young forms that differ considerably from the juveniles and adults), when they do occur, differ in structure from the larvae of nonchordates. Internal fertilization, viviparity (giving birth to young that have undergone embryological development), and parental care are common in tunicates and vertebrates.
Panthera
Tigers reproduce the same as all mammals do, with the male providing the sperm and the female providing the egg. Copulation between tigers begin when tigers reach sexual maturity. For females it is between ages 3 and 4, and ages 5-6 for males. Tigers have mating seasons in which they copulate. It is usually during monsoon periods when tigers are in their natural habitat. It can also occur after the monsoon period. Anole Carolenesis- lizards reproduce through copulation. The male lizard gives off a strong scent during the mating season (summer and spring) which attracts females. The male is on able to penetrate from the top, therefore it penetrate from the side. The eggs grow and hatch inside the female, then the female gives birth to the lizards. Some species of lizard only contain a female gender. This species reproduces by laying unfertilized eggs which hatch only as females. hat Rana Temporaria- reproduction of frogs is a little different than the other Chordata because the females eggs are fertilized outside the body. The male latches onto the female and releases its sperm while the female releases the eggs. The eggs (called spawn) are left in a pond until they are ready to hatch into possibly hundreds of tadpoles. |