Q. The cell walls of bacteria, fungi, and plant cells and the extracellular matrix of animal cells are all external to the plasma membrane. Which of the following is a characteristic of all of these extracellular structures?

a. They are composed of the mixture of lipids and carbohydrates.

b. They are constructed of materials that are mainly synthesized in the cytoplasm and next transported out of the cell.

c. They should block water and small molecules in order to regulate the exchange of matter and energy with their environment.

d. They should provide a rigid structure that maintains an appropriate ratio of cell surface area to volume.

e. They should permit information transfer between the cell's cytoplasm and the nucleus.