Which of the following animals uses the largest percentage of its energy budget for homeostatic regulation?
a. Marine jelly (an invertebrate)
b. Snake in a temperate forest
c. Desert insect
d. Desert bird

Verified step by step guidance

1. Understand the concept of homeostasis: Homeostasis refers to the ability of an organism to maintain internal stability by regulating its physiological processes, despite external changes.
2. Consider the energy budget: An animal's energy budget is the allocation of energy for various physiological processes, including growth, reproduction, and homeostatic regulation.
3. Identify the environments: Each animal lives in a different environment, which affects its energy allocation for homeostasis. For example, a desert bird must regulate its body temperature and water balance in a hot, dry environment.
4. Compare the animals: Evaluate how each animal's environment might demand more energy for homeostatic regulation. Animals in extreme environments, like deserts, often require more energy to maintain homeostasis.
5. Determine the likely candidate: Based on the environmental demands, consider which animal likely uses the largest percentage of its energy budget for homeostatic regulation. Desert birds, for instance, may need significant energy to regulate temperature and hydration.

Key Concepts

Homeostasis

Homeostasis refers to the process by which organisms maintain a stable internal environment despite external changes. This involves regulating factors like temperature, pH, and hydration. Animals expend energy to achieve homeostasis, with endotherms typically using more energy than ectotherms due to their need to maintain constant body temperatures.

Endotherms vs. Ectotherms

Endotherms, such as birds and mammals, generate heat internally to maintain body temperature, often requiring a significant portion of their energy budget. In contrast, ectotherms, like reptiles and insects, rely on external heat sources, using less energy for temperature regulation. Understanding this distinction helps determine which animals expend more energy on homeostasis.

Energy Budget

An animal's energy budget is the allocation of energy for various physiological processes, including growth, reproduction, and homeostasis. The percentage of energy dedicated to homeostasis varies among species, influenced by factors like metabolic rate and environmental conditions. Animals in extreme environments or with high metabolic demands often allocate more energy to maintaining homeostasis.