Which statement best describes a cause and its effect that occurs during the process of muscle contraction? A.
The presence of calcium ions within nerve cells causes the sarcomere to shorten.
B.
The pull of myosin on actin causes the motor neuron to send a nerve impulse.
C.
The release of calcium ions causes myosin and actin to attach to each other.
D.
The shortening of the sarcomere causes the release of calcium around the myofibrils.

uh two lol

a community that experiences major changes undergoes progress

the generally accepted parts of modern cell theory include: all known living things are made up of one or more cells. all living cells arise from pre-existing cells by division. the cell is the fundamental unit of structure and function in all living organisms.

the unequal cytoplasmic division that  results  in  one egg  and three polar bodies ensures that a fertilized  egg has  ample nutrients  forits journey  to  the uterus.