The valves in the heart open and close to move blood in between heart chambers. O a) three directions O b) two directions O c) four directions d) one direction

  d) one direction

Explanation:

The purpose of the various valves in the circulatory system is to keep blood flowing in one direction. The valve opens to allow blood flow one way, and closes to prevent blood flow the other way.

Hi,

The valves in the heart open and close to move blood in between heart chambers.

d) one direction

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