Biology MCQs

Notes:
The thyroid gland is the largest endocrine gland in the body. These glands are found in front of the neck. It is found at the bottom of the throat, in the middle of the trachea.

Notes:
Cancer is the most fatal non-infectious disease. In cancer, some cells in the body grow uncontrollably and spread to other parts of the body.

Notes:
4 tall plants and 1 medium height plant is totally impossible outcome of Mendel’s Experiment. Gregor Mendel discovered the fundamental laws of inheritance through his work on pea plants. They concluded that genes come in pairs and are inherited as separate units, one from each parent.

Notes:
Cyanobacteria, also known as blue green algae, are single-celled and belong to the family of Prokaryotes. That means, they do not have a well defined cell nucleus. The ability of cyanobacteria to perform oxygenic photosynthesis is thought to have converted the early reducing atmosphere into an oxidizing one, which dramatically changed the composition of life forms on Earth by stimulating biodiversity and leading to the near-extinction of oxygen-intolerant organisms.

Notes:
Biomagnification is the sequence of processes in an ecosystem by which higher concentrations of a particular chemical such as the pesticide DDT, are reached in organisms higher up the food chain. It’s principal cause is eutrophication of stagnant water leading to the increase in BOD level. The some biomagnifcation has led to the ban on the use of DDT as a pesticide.

Notes:
In the blood the key minerals are iron, copper, zinc, sodium, potassium, calcium and magnesium. Minerals constitute important part of blood plasma that constitutes almost 55% of blood. In the blood, iron is found in larger amounts than any other mineral.

Notes:
Human African trypanosomiasis, sleeping sickness, African lethargy, or Congo trypanosomiasis is a parasitic disease of people and animals, caused by protozoa of the species Trypanosoma brucei and transmitted by the tsetse fly. The tsetse fly is a large, brown, biting fly that serves as both a host and vector for the trypanosome parasites.

Notes:
The chromosomes which determine the sex (maleness or femaleness) of an individual in sexually producing organisms are called sex chromosomes or allosomes. In humans an individual whose cells contain XX chromosomes (homo or isogametic) becomes a female, while one whose cells contains XY chromosomes (heterogametic) becomes a male.

Notes:
Organ donation is the process of donating organs or biological tissue to a living recipient, who is in need of a transplant. The eyes of a dead person can be used only if they are taken out within 6 hrs of death. Only corneal blinds can be benefitted through this process not other Blinds.

Notes:
Lactobacillus acidiphilous is used in milk curdling by producing lactic acid and reducing the pH of the milk. These bacteria convert the lactose into lactic acid, which imparts the sour taste to curd. It is a genus of Gram positive facultative anaerobic or microaerophilic rod-shaped bacteria.