Final answer:
The mitochondrion is the organelle in eukaryotic cells responsible for cellular respiration, producing ATP by breaking down organic molecules with oxygen.
Step-by-step explanation:
Mitochondria: The Powerhouses of Cells
The organelle referred to in the question is the mitochondrion (mitochondria, plural), a cellular structure that is crucial for cellular respiration in eukaryotic cells. Mitochondria are often called the "powerhouses" or "energy factories" of the cell due to their role in generating ATP (adenosine triphosphate), which is the cell's main energy-carrying molecule. The process of cellular respiration occurs within these organelles, where organic molecules such as glucose are broken down using oxygen. This reaction yields energy, which is captured in the form of ATP, and also produces carbon dioxide as a waste product.
During cellular respiration, the mitochondria synthesize ATP by harnessing the chemical energy found in the breakdown of nutrients. This ATP is then readily available to be used for various cellular activities, such as movement, cell division, and other metabolic processes. The number of mitochondria within a cell can vary according to the energy requirements of the cell, with more active cells containing a greater number of mitochondria.