The function of muscular contractions that force water into the tube feet is
a. regeneration.
b. allowing the echinoderm to float with ocean currents.
c. digestion.
d. to enable the echinoderm to attach to surfaces.

Viruses can be transmitted through air, water, food, insect bites, and direct skin contact. once a virus gains entry into the body, it invades a host cell in order to? a. synthesize antibodies for defense b. deactivate the host cell's defenses c. access cell processes for reproduction d. metabolize host proteins and grow