Biology Questions

Aestivation is summer sleep. Many organisms like the snails do not find it comfortable in summer. They withdraw and lead a life with reduced BMR (basic Metabolic Rate) in a state of  dormancy.

The molecules responsible for membrane transport are proteins.

Tuberculosis (TB) is caused by a type of bacterium called Mycobacterium tuberculosis.

It's spread when a person with active TB disease in their lungs coughs or sneezes and someone else inhales the expelled droplets, which contain TB bacteria.

One would have to spend prolonged periods (several hours) in close contact with an infected person to catch the infection yourself.For example, TB infections usually spread between family members who live in the same house. It would be highly unlikely for you to become infected by sitting next to an infected person on a bus or train. Hence, statement 1 is incorrect.

Saprophytic fungi feed on dead plant and animal remains. Many are extremely beneficial, breaking down this organic material into humus, minerals and nutrients that can be utilised by plants. Agaricus is one among them.