Answer:
A. keeps you healthy
Explanation:
The immune system protects your body from outside "invaders," such as bacteria, viruses, fungi, and toxins.
B is your answer because when two hydrogen atoms enter the ETS as part of either NADH or FADH2, the two hydrogen atoms are split into two H+ and two electron.
Answer:
you didn't give us the descriptions
Explanation:
Fossils
Vestigial structures
Homologous structures
Molecular evidence
Comparative embryology
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