In organisms, heat loss or heat gain is a function of ‘X’. Heat production is proportional to ‘Y’. Select the option that correctly identifies ‘X’ and ‘Y’.

 

Heat loss or heat gain is a function of surface area. Since small animals have a larger surface area relative to their volume, they tend to lose body heat very fast when it is cold outside; then they have to expend much energy to generate body heat through metabolism.

Heat production is proportional to the body volume. Large animals can produce more heat.

Warm blooded animals living in colder climates tend to be larger than their counterparts in warmer climates. Large animals have lower surface to volume ratio. Smaller surface minimises heat loss and higher volume increases in heat production.