Hypersensitivity of body to certain external or internal agents is called

A condition in which body's internal environment remain nearly costant is called:

A person shows strong unusual hypersensitive reactions when ecposed to certain substances present in the air, identify the condition.. Name the cells responsible for such reactions. What precaution should be taken to avoid such reactions.

Fill ups The curved surface area of a hollow cylinder of height h with external and internal radius as R and r is……………. .

Opening in the core tissue which permit exchange of gas between atmosphere and internal tissue is called

The scientific process by which crop plants are enriched with certain desirable nutrients is called:

Differentiate external respiration and internal respiration.