Humber Admissions Practice Test 2026 - Free Practice Questions and Study Guide for Humber College Admissions

The mitochondria are known as the powerhouse of the cell, primarily responsible for the production of adenosine triphosphate (ATP), which is the main energy currency of the cell. This organelle carries out oxidative phosphorylation, a process that generates ATP through the electron transport chain and chemiosmosis. Mitochondria are specially adapted for this task, possessing a double membrane structure, with the inner membrane being highly folded into structures called cristae to increase the surface area for energy production processes.

In contrast, ribosomes are responsible for protein synthesis but do not produce ATP. The nucleus is the control center that houses genetic material and is involved in regulating gene expression and cell division, but it does not contribute to ATP synthesis. The endoplasmic reticulum plays a crucial role in the synthesis and processing of proteins and lipids but is also not involved in ATP production. Thus, the mitochondria are unequivocally the organelles that are primarily associated with ATP production, making this option the correct one.