Final answer:
Animals need to consume food regularly to obtain energy for cellular respiration, which allows them to grow, a fundamental aspect of being a living organism that encompasses development and maturation.
Step-by-step explanation:
Animals need to eat on a regular basis because cellular respiration requires a constant supply of energy. This energy is essential for various life processes, including creating motion and options such as reproduce, grow, respire, and excrete. Among the options provided, the most comprehensive one would be to grow, as growth encompasses increasing in size, developing, and maturing, which is a fundamental aspect of living organisms. Additionally, growth is a process that requires a significant amount of energy, which is obtained through the nutrients and substances consumed by animals.
All living organisms are composed of one or more cells and need energy to carry out life processes such as responding to their environment and maintaining a stable internal environment. To grow and reproduce, organisms must exchange matter with the environment, which provides them with the necessary resources to fuel these processes. Energy from food allows for cellular activities and body functions that are crucial to survival and well-being.