Question

which of the cell types most likely contains the greatest number of mitochondria? a. smooth muscle cells, because digestion is a constant process requiring constant energy b. blood cells, because they must carry oxygen throughout the body all the time, which requires energy c. epidermal cells, because the skin must constantly grow new skin cells, which requires energy d. cardiac muscle cells, because the heart must work all the time, requiring constant energy cell types blood epidermal cardiac smooth muscle

Explanation:

To determine which cell type has the most mitochondria, we analyze the energy needs of each:

• Option A: Smooth muscle cells (e.g., in digestion) have some energy needs, but not as high as cardiac muscle.
• Option B: Blood cells (red blood cells lack mitochondria; others have moderate needs).
• Option C: Epidermal cells grow, but their energy demand is less than cardiac muscle.
• Option D: Cardiac muscle cells (heart) contract continuously, requiring constant energy (ATP), so they need many mitochondria for energy production.

Answer:

D. cardiac muscle cells, because the heart must work all the time, requiring constant energy