Answer any three questions.

Tolerance in biology refers to the ability of an organism or a biological system to endure or adapt to a particular environmental condition, substance, or stress without significant harm. It describes the range of conditions an organism can survive in.

a) ii)

Blood transports various essential materials throughout the body. Four such materials are:

• Oxygen
• Carbon dioxide
• Nutrients (e.g., glucose, amino acids)
• Hormones