The main factor that controls the rate of breathing is..
A.) concentration of carbon dioxide.
If we think about it.. When we breath in oxygen, right away it enters your lungs and turns into carbon dioxide. Well since your lungs need to process oxygen and bring oxygen into the blood stream. Then as soon as the oxygen comes inside (inhale) the oxygen turns into carbon dioxide and you breath it out (exhale) to get a new oxygen load.
Makes sense? lol
Good Luck! :)
NATIONAL ems education standards
It serves to digest food particles.
<span>The two
membranes of the mitochondria and the inner and outer membranes of the
chloroplast have similar functions. The external membrane of the mitochondria
serves as covering of the organelle to protect it; while the internal lining
which is folded repeatedly in layers contains proteins. Likewise, the
chloroplast has inner and outer membranes too that contain and protect its
different parts such as the stroma and thylakoids.</span>
<span>A. Arthritis only affects old people.
Arthritis can affect many people, even children
hope this helps
</span>