Exam 15: Energy Balance and Thermal Physiology

Metabolic thermoregulators are considered ____ since they rely on (bio)chemical reactions to maintain their body temperature when they are losing heat to the environment.

Poikilothermic ectotherms that live in thermally variable environments manage to maintain a relatively stable body temperature.

One of the ways that birds retain internal heat involves behavioral insulation.

Explain how countercurrent heat exchange is used in maintaining core bod temperature.

Leptin stimulates the hypothalamus to secrete ________, which in turn acts to _____ appetite.

In birds, the hypothalamus does not

According to the second law of thermodynamics, as life become more organized the environment becomes disorganized.

While working outside on a hot day the wind blows making you feel cooler. This is most likely due to heat loss through

Skeletal muscle myosin from lizard shows maximal ATPase activity over a wide range of temperatures. This is due to the fact that

Match each sentence with the most appropriate choice: -Rete mirabile

Match each sentence with the most appropriate choice: -Water

Leptin signaling is the dominant factor responsible for long-term balance of total body energy.

Regional heterotherms are animals that are

Vasoconstriction helps an animal retain heat by

Many biological processes, e.g. enzyme-catalyzed reactions, have a temperature optimum. Explain why activity increases as temperature rises, reaches a maximum, and then decreases. What is the evolutionary/adaptational significance of the temperature optimum?

Respirometry can be used to measure minimal metabolic rate.

Match each sentence with the most appropriate choice: -Regional heterothermy

BMR and SMR are constant for a species.

Polar bears have black skin. This characteristic helps them deal with cold stress by

When a bird ruffles its feathers in response to heat stress it