By: Andrew Kiarie-Mumbi
Introduction To Cnidaria
The Normal cnidarian reproduction involves both sexual and asexual reproduction. In sexual reproduction a larva known as a planula develops into a zygote, it then settles in a safe location where it develops into an adult polyp. The polyp reproduce asexually into a medusae that develops gonads which forms gamete that allows it to reproduce sexually later in life. In asexual reproduction a, new individual develops from a tissue that is budded off from the parent plant., or by a parent dividing crosswise into smaller individuals. Polyps that remains physically attached to each other in a common mass of time constitute a colony.
The Normal cnidarian reproduction involves both sexual and asexual reproduction. In sexual reproduction a larva known as a planula develops into a zygote, it then settles in a safe location where it develops into an adult polyp. The polyp reproduce asexually into a medusae that develops gonads which forms gamete that allows it to reproduce sexually later in life. In asexual reproduction a, new individual develops from a tissue that is budded off from the parent plant., or by a parent dividing crosswise into smaller individuals. Polyps that remains physically attached to each other in a common mass of time constitute a colony.
Box Jellyfish (Chironex Fleckeri)
Box jelly fish can undergo a gametic reproduction through meiosis and asexual, without sex. During spring a box jelly fish swims around looking for a mating partner. Once they meet the female release her eggs and the male release his sperms on fresh water. The two partners dies after reproducing. After fusing together the egg and sperm forms a fertilized zygotic cell that goes through mitosis and form a planulae. The planulae grow into a polyp that is approximately 1-2 millimeters length, it has two tentacles attached to it. These tentacles are used to attach it on hard surface. During the polyps stage they can also undergo another form of reproduction known as budding. A new offspring grows on the parent polyps and swim down from the freshwater rivers into the ocean until it is fully sexually matured.
Stalked Jellyfish (Stauromedusae)
Stauromedusae can reproduce asexually by budding (this usually occurs in the spring). The polyp forms buds that break off to become unciliated planulae that will develop into adult Stauromedusae polyps. Unlike most jellyfish, stalked jellyfish do not have strobilization, the process where the polyp forms ephyrae (jellyfish larvae in the medusa form) that break off and develop into adult jellyfish. Stalked Jellyfish do not undergo through alteration of generation unlike other jellyfishes. Instead they remain in the polyps stage throughout their adulthood stage.. Sexual reproduction occurs during the polyp stage. Stauromedusae reproduce sexually by external fertilization and have separate male and female sexes. In the summer, the male and female jellyfish release their eggs and sperm into the water and the egg is fertilized.he planulae travel in large groups until they mature.. Alone, they are unable to catch any food and will soon die, but when traveling in groups the planulae can catch and eat small organisms. After a few days the planulae develop into juvenile polyps. The immature polyp develops into an adult through metamorphosis where it gains its adult organs, including gonads, ocelli (simple eyes), circular coronal (around the head) muscles, and rhopalioids.
Portuguese Man of War jellyfish (Physalia Physalis)
The portuguese man of war is a siphonophore, an animal made up of many animals working together. This animals is made up of for parts. The part responsible for reproduction is known as Gonozooids. The Adult medusa releases sperms which fertilizes the egg. The egg form a larva, which finds a place in to the gonozooid. These gonozooids polyps eventually release a medusa form from asexual budding that grows into the adult medusa which started the cycle.