Final answer:
Mice that lack insulin receptors in the brain are prone to altered metabolism, which can lead to obesity and other health problems.
Step-by-step explanation:
Mice that lack insulin receptors in the brain are prone to altered metabolism. Insulin receptors play a crucial role in regulating glucose uptake in cells, and without these receptors, the cells are unable to take up glucose properly. This leads to impaired metabolism and can contribute to the development of obesity and other health problems.