Reference Notes | Zoology
Plasmodium – Asexual and Sexual Reproduction Cycle in Mosquito
For: Biology | Science Class 11
It is a kind of protozoa, which causes malaria. A French microbiologist Charles Laveran in 1880 discovers plasmodium in the blood of patient suffering form Malaria. In RBC, he found a cell which is amoeba like and this structure was not found in healthy man. Then he injected the blood of patient to the healthy man them the healthy man suffered from fever soon.
There are four species of malarial parasites.
Plasmodium vivax: It produces fever at every 48 hours. This is mostly found in India and Nepal.
Plasmodium malariae: It produces fever at every 72 hours.
Plasmodium falciperum: It produces continuous fever with high temperature
Plasmodium ovalae: It produces night fever.
Sexual Cycle in Mosquito
In Stomach of the mosquito, macrogametocyte produces ovum and microgametocyte produces four to eight flagellate sperms. Now one of the sperm fertilizes ovum and when sperm penetrates the ovum zygote is formed. The cycle from the formation of gametocytes to the formation of zygote is called sesual cycle and it is termed as Gamogony.
Asexual Cycle in Mosquito
The zygote in the stomach of mosquito show movement and becomes elongated and called ookinete. The ookinete moves and get attached to the wall of stomach. At this stage, ookinete becomes thick walled and called as oocyst. The oocyst becomes large thick walled and nucleus undergoes multiple divisions to produce number of nuclei. Within oocyst groups of cytoplasm having many nuclei are formed called sporoblast. The sporoblast gets ruptured and number of spindle shaped structures comes out which are called sporozoites. Now sporozoites move towards salivary glands so that it can again enter to the man’s body.
The process from the formation of zygote to the formation of sporozoites is called Sporogony. Hence, half sexual cycle takes place in man and half takes place in mosquito. If mosquito does not eat gametocytes they degenerate in human body.
Symptoms of malaria
Fever, chilling, sweating, weakness, nausea, vomiting, loss of apetite, loss of weight.
use mosquito net, antimosquito cream or oil, antimosquito coil or mat, screening in door and windows, Removing bushes and water from the surrounding, spreading of kerosene oil in polluted water, DDT or insecticide should be sprayed, Mosquito larva eating fishes should be introduced in the water.
……………Phylum : Protozoa
………………………Genus : Plasmodium
…………………………….Species : vivax