Tag: protozoa: benefits and harmful effects

Leucorrhoea, commonly known as whites, refers to a whitish discharge from the female genitals caused by the presence of infection in vaginal tissues. 

Pond scum is a massive growth of algae on the surface of the pond or any stagnant water source. 

The Paramecium is a unicellular ciliated protozoan. It looks an oval, slipper-shaped micro-organism when observed under a microscope, rounded at the front/top and pointed at the back/bottom. It can also be seen by naked eyes.

In Paramoecium, reproduction takes place by binary fission method. At first, micronucleus divides into 2 nuclei by mitosis. The cytopharynx also divides into 2 parts. The cytoplasm is also divided into 2 parts. Then transverse constriction is made from two sides. New contractile vacuoles are formed. The constriction meet at centre and two daughter paramecia reproduced. Thus, the correct answer is option D.

The term 'lates' is likely a typo for 'lates' (referring to Lates calcarifer, the barramundi or Asian sea bass), which is a catadromous fish often found in estuaries.

Pond scum is a massive growth of algae on the surface of the pond or any stagnant water source. They are autotrophic in nature due to the green compound present which helps in photosynthesis, these pigments are called chlorophyll.

• The parasite which causes malaria, Plasmodium requires two different hosts a vertebrate intermediate host, such as a human, and an insect definitive host, also known as the vector i.e female Anopheles mosquito. 
• When the mosquito bites humans it ingests blood cells containing gametocytes. The mosquito digests the blood cells, releasing the male and female gametes, which fuse together and burrow into the mosquito’s gut wall, where they mature inside oocysts.
• After 8-15 days (depending on the species) the oocysts burst and sporozoites are released into the body cavity of the mosquito. From there, they travel to the salivary glands. when the mosquito bites these infective sporozoite enters the blood of the humans.
• Hence sporozoites are the infective stages of the malaria parasite is found in salivary glands of the mosquito.
• So, the correct answer is 'Salivary glands of mosquito'.

The plasmodium parasite is spread by female Anopheles mosquitoes, which are known as "night-biting" mosquitoes because they most commonly bite between dusk and dawn. If a mosquito bites a person already infected with malaria, it can also become infected and spread the parasite on to other people.

Diphyllobothrium is a genus of tapeworms which can cause diphyllobothriasis in humans through consumption of raw or undercooked fish. The principal species causing diphyllobothriasis is Diphyllobothrium latum, known as the broad or fish tapeworm, or broad fish tapeworm.

Taenia solium, is the pork tapeworm, a tapeworm belonging to the cyclophyllid cestode family .