Question

10. What is true with respect to thermoregulation?

a. Endotherms do not use behavior to control heat exchange with the environment

b.Thermoregulation is important because temperature affects movement of chemical substances across the membranes of cells

c.In mammals, the sinoatrial node serves as the physiological sensor/control center for body temperature

d. Ectotherms do not produce any heat in metabolic reactions

Answer 1

Option A is the most appropriate answer as endotherms produce their heat by metabolic activity and there is no need to use behaviour to control temperature.

Both option B and C are entirely wrong.

Coming to option D, Ectotherms usually do not use metabolic heat for their temperature regulation, instead they use behavioural adjustment and temperature changes with the environmental temperature. But the option says that they do not produce any heat in metabolic reaction. Ectotherms do produce slight metabolic heat but they do not use that heat for thermoregulation. Heat is produced during most cellular metabolic reactions. Hence the option is false.