Which process is primarily responsible for energy extraction in living organisms?

Cellular respiration is the primary process responsible for energy extraction in living organisms. This metabolic pathway occurs in the cells and involves breaking down glucose and other organic molecules in the presence of oxygen to release energy. This energy, stored in the form of adenosine triphosphate (ATP), is essential for powering various cellular activities and functions.

In contrast to photosynthesis, which is the process by which plants, algae, and some bacteria convert light energy into chemical energy using carbon dioxide and water, cellular respiration focuses on extracting that stored energy for use by living organisms. While fermentation is another method that some organisms, especially in anaerobic conditions, use to obtain energy without oxygen, it is less efficient than cellular respiration. Additionally, cell division is a vital biological process related to growth and reproduction, but it does not directly relate to energy extraction. Thus, cellular respiration stands out as the dominant process through which energy is harnessed and made available to cells in living organisms.