Answer:
C. Plants release carbon dioxide and take in oxygen through the xylem in leaves.
Explanation:
Plants exchange gas with the atmosphere and release carbon dioxide and take in oxygen through the xylem in leaves.
It is strengthened by data which is always contradictory.
A energy barrier must be overcome.
Answer:
Definition. (1) The combination of oxygen with a substance forming oxide. (2) A chemical reaction in which there is the loss of electrons or gain (or increase in the proportion) of oxygen, hence, resulting in an increase in oxidation state by a molecule, atom or ion.
I would say that B) single events or several causes working together to produce extinction in a short period is referred to as mass extinction, but I am not 100% sure.
