When comparing relatively small mammals, such as mice and shrews, to large mammals, such as elephants and horses, the mice and shrews have
A) higher basal metabolic rates.
B) more white fat.
C) lower average blood glucose levels.
D) less metabolically active tissues, such as skin and fat.
E) countercurrent heat exchange.

Question

Quizplus · Accepted Answer

Smaller animals have higher metabolic rates per unit of body mass than larger animals, which allows them to maintain a higher body temperature relative to their environment. This is due to their high surface area to volume ratio, resulting in greater heat loss to the environment. To compensate for this heat loss, smaller animals have a higher basal metabolic rate.

Answer: D
 Smaller animals have relatively less metabolically active tissues, such as skin and fat, than larger animals. This is because a larger animal has a greater need for insulation and energy storage, which necessitates more metabolically active tissues.

When Comparing Relatively Small Mammals, Such as Mice and Shrews