Cellular respiration releases energy by breaking down
a
food molecules- glucose
b
ATP
c
carbon dioxide
d
water
a) food molecules - glucose
Cellular respiration releases energy by breaking down food molecules, specifically glucose.
The correct answer is b) ATP.
To understand why ATP is the correct answer, it is important to understand the process of cellular respiration. Cellular respiration is the metabolic process that occurs in cells to convert energy stored in food molecules into a usable form of energy called ATP (adenosine triphosphate).
During cellular respiration, several steps occur. The first step is glycolysis, which takes place in the cytoplasm. In glycolysis, glucose, a type of food molecule, is broken down into two pyruvate molecules, resulting in the production of a small amount of ATP.
The next steps of cellular respiration, which include the citric acid cycle and oxidative phosphorylation, take place in the mitochondria. In these steps, pyruvate is further broken down to release carbon dioxide and water as waste products. However, the main purpose of these steps is to generate a large amount of ATP.
The majority of ATP synthesis occurs in the oxidative phosphorylation step. In this step, electrons from food molecules, such as glucose, are transferred through a series of protein complexes in the inner mitochondrial membrane. As electrons pass through these complexes, protons are pumped across the membrane, creating a proton gradient. This gradient is then used by an enzyme called ATP synthase to produce ATP.
Therefore, it is ATP that is ultimately released as the usable form of energy during cellular respiration. Carbon dioxide and water are waste products that are produced during the breakdown of food molecules but do not serve as the main source of energy release.
In summary, cellular respiration releases energy by breaking down food molecules, such as glucose, but ATP is the primary form of energy released, while carbon dioxide and water are waste products.