University of Edinburgh
 

BSL Biology Glossary - valve - definition

Definition: Valves are like gates inside your veins and arteries. The blood flows round your body and the gates open to let the blood go past. The blood can only go one way round your body. The gate of the valve shuts so that the blood can't flow back the wrong way. You have valves inside your heart too.

circulation

reproduced by permission from Hodder