When exposed to cold temperatures, which of the following is responsible for maintaining constant body temperature in humans?
1. Vasoconstriction and shivering
2. Vasodilation and shivering
3. Vasodilation and sweating
4. Vasoconstriction and sweating

What percent of animals cannot maintain a constant internal environment?
1. 1 %
2. 25 %
3. 45 %
4. 99 %

Very small animals are rarely found in polar regions because:

Keoladeo National Park, host to migratory birds from Siberia, is in:

In animals, the organism, if unable to migrate, might avoid the stress by escaping in time. All the following would exemplify this except:

Under unfavorable conditions, many zooplankton species in lakes and ponds are known to enter a stage of suspended development called as:

Any attribute of the organism that enables the organism to survive and reproduce in its habitat is called as:
1. Adaptation
2. Phenotypic plasticity
3. Acclimatization
4. Norm of the reaction

All the following are adaptations in desert plants to minimize water loss except:
1. Thick cuticle
2. ${\mathrm{C}}_3$ photosynthesis
3. CAM pathway
4. Sunken stomata

According to Allen’s rule:

A thick layer of fat, blubber, beneath the skin is found in:
1. Terrestrial mammals of colder climates
2. Aquatic mammals of colder climates
3. Terrestrial mammals of warmer climates
4. Aquatic mammals of warmer climates