Which statement best describes energy release in cellular respiration? (1 point)
Responses
Stored chemical energy can be used immediately and is released in the cytoplasm.
Stored chemical energy can be used immediately and is released in the cytoplasm.
Stored chemical energy can be used immediately and is released in the mitochondria.
Stored chemical energy can be used immediately and is released in the mitochondria.
Stored chemical energy is broken down and released in the cytoplasm.
Stored chemical energy is broken down and released in the cytoplasm.
Stored chemical energy is broken down and released in the mitochondria.
Stored chemical energy is broken down and released in the mitochondria.
Stored chemical energy is broken down and released in the mitochondria.
The correct statement is:
Stored chemical energy is broken down and released in the mitochondria.
The correct statement that best describes energy release in cellular respiration is: Stored chemical energy is broken down and released in the mitochondria.
To arrive at this answer, it is important to understand the process of cellular respiration. Cellular respiration is the process by which cells convert stored chemical energy, typically in the form of glucose, into usable energy in the form of ATP (adenosine triphosphate).
The process occurs in multiple steps: glycolysis, the Krebs cycle, and oxidative phosphorylation, all of which take place in different parts of the cell. Glycolysis initially occurs in the cytoplasm, where glucose is partially broken down into pyruvate molecules, releasing a small amount of energy in the form of ATP.
However, the majority of ATP production occurs in the mitochondria. The pyruvate molecules produced during glycolysis are transported into the mitochondria where they undergo further breakdown via the Krebs cycle, also known as the citric acid cycle. The Krebs cycle converts the pyruvate molecules into carbon dioxide, producing additional ATP and energy-rich molecules, such as NADH and FADH2.
The energy-rich molecules NADH and FADH2 generated during the Krebs cycle then enter the electron transport chain, which is embedded in the inner membrane of the mitochondria. Through a series of redox reactions, the electron transport chain generates a flow of protons (H+) across the inner membrane, leading to the formation of a high concentration of protons in the intermembrane space. This proton gradient drives the synthesis of ATP through a process called oxidative phosphorylation.
Therefore, the statement that accurately describes energy release in cellular respiration is that stored chemical energy is broken down and released in the mitochondria.