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

instead of copying and pasting things off of tests or work done on computer which im sure you did, try and read over the question carefully

bacteria could be both, harmful and to us. harmful bacteria could make us sick and probably even by getting the chances of getting a disease, but good bacteria fight it off with your immune system. there is always bacteria everywhere we go. we need to make sure to wash our hands after using the restroom, before eating, after eating, after petting an animal too. so you see, bacteria is everywhere and is harmful or . i hope this . : ) : ) : )