Final answer:
Food must be broken down into smaller molecules like glucose to be absorbed into the bloodstream, transported to cells, and converted into ATP for energy necessary for cellular functions.
Step-by-step explanation:
Why Must Food Be Broken Down?
Food must be broken down on a cellular level because the complex molecules it contains are not directly usable by cells. The breakdown of food into smaller, more simple molecules enables their absorption into the bloodstream, where they can be transported to cells to be used in various ways. The correct answer to the question is b) To convert food into energy for cellular functions.
Importance of Breaking Down Foods
The body requires food for energy, building materials, and control of body processes. Carbohydrates are broken down into glucose, which is then used to produce ATP through cellular respiration. ATP serves as the currency for energy within cells, allowing them to perform essential functions. Additionally, breaking down foods is a prerequisite for synthesis of cellular building blocks, such as large proteins from amino acids and moving signaling molecules like hormones. It is also essential for eliminating excess waste and potential toxins, ensuring cells stay healthy.
Without breaking down foods, nutrients could not be assimilated into the forms necessary for energy production, growth, repair, and maintenance of cellular functions. Moreover, essential nutrients that cannot be produced by the body need to be ingested in their simplest form through a balanced diet to be utilized effectively.