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.

Match the types of competition to their descriptions.

Suppose you are estimating the size of a blue crab population. what is the population size if the number marked in the first catch is 40, the total number in the second catch is 200, and the number marked in the second catch is 50?

Due tonight 10 points will mark brain