About: http://webisa.webdatacommons.org/405248091

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	Why do some of the larger veins have valves in them?Larger Veins have valves because venous pressure is often not great enough (as the blood must overcome gravity and other forces) to return the blood to the heart.
http://www.w3.org/ns/prov#wasQuotedFrom	easynotecards.com