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jeka57 [31]
4 years ago
15

How do veins return blood to the heart? select all that apply?

Biology
1 answer:
Jobisdone [24]4 years ago
6 0
A relatively small blood pressure gradient is generally insufficient to move blood through the veins under given conditions, thus venous return must be facilitated by valves within veins and two "pumps." ... As skeletal muscles contract, veins are squeezed to help propel the blood toward the heart.
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