Question

which of the following is true about the cells of the human body?
a. all cells in the human body are shaped like discs and contain one nucleus.
b. the genetic information contained in cells differs between cell types.
c. environmental factors cannot influence the development of a cell.
d. different cells perform different functions within the human body.

Explanation:

• Option A: Not all cells are disc - shaped. For example, nerve cells have long extensions. Also, some cells like red blood cells (in humans) lose their nucleus as they mature.
• Option B: All somatic cells in the human body (except for some cells like red blood cells that lose their nucleus) have the same genetic information. The difference in cell types is due to gene expression, not different genetic information.
• Option C: Environmental factors can influence cell development. For example, exposure to certain chemicals or radiation can affect how cells grow and differentiate.
• Option D: This is a fundamental concept in human biology. Different cells, such as muscle cells (for contraction), nerve cells (for signal transmission), and epithelial cells (for protection and secretion) have distinct functions.

Answer:

D. Different cells perform different functions within the human body.