Answer:
The valves' main job is to keep the blood moving in one direction – back up towards the heart. When the valve is open, blood freely flows upward towards the heart and when the valves are closed, blood cannot flow back
The answer is D) proteins
The purpose of meiosis<span> is to reduce the normal diploid cells to haploid cells, called gametes.
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A: Energy hope this helps
I can’t really see the questions
