<span>B. 4-8 weeks
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I believe the answer is D) ATP is too unstable
Answer: The integumentary system helps the immune system by The skin acts as a barrier to keep out pathogens (B)
Explanation:
Answer:
The circulatory system is divided into systemic circulation and pulmonary circulation.
Explanation:
Systemic circulation carries oxygenated blood from the left ventricle to the rest of the body while pulmonary circulation carries deoxygenated blood away from the right ventricle.