Question

Which cell organelles play a role in energy production by either building food molecules or breaking them down?


I.nucleus
II.mitochondrion
III.chloroplast
IV.cell membrane

A.
I and II only

B.
II and III only

C.
III and IV only

D.
I, II, III, and IV

Answer 1

The correct answer is **B. II and III only**.

Here's the breakdown:

- **Nucleus (I)**: The nucleus is primarily involved in storing genetic information and regulating gene expression. It does not directly participate in energy production.

- **Mitochondrion (II)**: Mitochondria are known as the powerhouses of the cell because they are responsible for producing ATP through cellular respiration, which involves breaking down food molecules.

- **Chloroplast (III)**: Chloroplasts are found in plant cells and are responsible for photosynthesis, a process that builds food molecules (glucose) using light energy, carbon dioxide, and water.

- **Cell membrane (IV)**: The cell membrane's primary function is to protect the cell and regulate the passage of substances in and out. It does not play a direct role in energy production.

Therefore, the organelles involved in energy production by either building (chloroplasts) or breaking down (mitochondria) food molecules are the mitochondrion and chloroplast.