What is the next step in muscle contraction after the actin changes shape?
a. myosin binds to actin.
b. a calcium ion binds to actin.
c. myosin and actin slide past each other.
d. an atp molecule binds to the myosin.

Why can't you grow plants with adhesion water?

Parasitism could be considered a form of which of these types of relationships? -mutualism -commensalism -predator-prey -mimicry

How are the testes and ovaries similar? a. both produce sex cells. b. both connect internal reproductive organs to the exterior. c. both transport sex cells from their site of production. d. both store mature sex cells.