Question

List three reasons why living organisms need energy for cell activities.Understanding: Energy released from carbon compounds by respiration is used in living organisms and converted to heat.

Answer 1

Living organisms require energy for (1) metabolic processes to synthesize complex molecules, (2) homeostasis to maintain internal balance, and (3) cellular respiration to break down nutrients for energy. The energy cycle with autotrophs and heterotrophs ensures this continuous energy flow.

Step-by-step explanation:

Living organisms require energy to sustain vital cellular activities. Here are three reasons explaining why:

Metabolic Processes: Energy is crucial for metabolic pathways, including the synthetic reactions to build larger molecules from smaller ones, such as proteins, lipids, nucleic acids, and carbohydrates.

Maintenance of Homeostasis: Organisms use energy to maintain a stable internal environment, essential for survival.

Cellular Respiration: Through the process of cellular respiration, organisms break down food to release the necessary energy to fuel all life functions.

Notably, the energy cycle is fundamental to life on Earth. Autotrophs capture energy through photosynthesis, creating carbohydrates that store chemical energy.

This energy is then transferred within ecosystems, with heterotrophs acquiring energy by consuming other organisms. Energy is not recyclable and is lost as heat, necessitating a constant input of energy for life to persist.