Answer:
Respiratory System and the Muscles of Inhalation and Exhalation. The muscular and nervous systems enable the involuntary breathing mechanism. The main muscles in inhalation and exhalation are the diaphragm and the intercontinental (shown in blue), as well as other muscles.
Answer:
Fertilization and mating generate variation, while physical change results in adaptation to the environment. *
For the answer to the question above, I will just complete the missing word for your statement.
<span>Regions of the CNS with an abundance of myelinated axons constitute the "White" matter. </span>
The answer is "white"
I hope my answer helped.