<P> Veins are present throughout the body as tubes that carry blood back to the heart . Veins are classified in a number of ways , including superficial vs. deep , pulmonary vs. systemic , and large vs. small . </P>
<P> Veins are present throughout the body as tubes that carry blood back to the heart . Veins are classified in a number of ways , including superficial vs. deep , pulmonary vs. systemic , and large vs. small . </P>
where are veins located in the human body
where are veins located in the human body
throughout the body
throughout the body