Tiny, thin-walled blood vessels that allow the exchange of gases and nutrients between the blood cells.<ref>Exploring Creation with General Science, by Dr. Jay L. Wile</ref>
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Tiny, thin-walled blood vessels that allow the exchange of gases and nutrients between the blood cells.<ref>Wile, Dr. Jay L. ''Exploring Creation Through General Science''. Anderson: Apologia Educational Ministries, Inc.