In vertebrate animals, brown fat tissue's color is derived from abundant blood vessels and capillaries. White fat tissue, on the other hand, is specialized for fat storage and contains relatively few blood vessels or capillaries. Brown fat cells have a specialized protein that allows protons to diffuse across the inner mitochondrial membrane. Which of the following might be the function of the brown fat tissue?
A) to increase the rate of oxidative phosphorylation from its few mitochondria
B) to increase the metabolic rate when it is especially hot
C) to increase the rate of ATP production
D) to regulate temperature by converting most of the energy from NADH oxidation to heat

Question

Quizplus · Accepted Answer

Brown fat tissue is specialized in generating heat by dissipating the energy from NADH oxidation as heat, a process called non-shivering thermogenesis. This helps regulate body temperature in hibernating animals, newborns, and some adult animals such as rodents, by increasing their metabolic rate and heat production. The specialized protein that allows protons to diffuse across the inner mitochondrial membrane is called uncoupling protein 1 (UCP1), and it uncouples oxidative phosphorylation from ATP synthesis, increasing the production of heat in brown fat cells.  A, B, and C are incorrect because brown fat tissue is not specialized in producing more ATP or oxidative phosphorylation, but in generating heat.

In Vertebrate Animals, Brown Fat Tissue's Color Is Derived from Abundant