MadSci Network: Medicine
Query:

Subject: how can blood flow back to the heart through the veins when someone is sitt

Date: Mon Mar 16 21:13:51 2009
Posted by Joshua
Grade level: 10-12 School: Hillel Yeshiva High School
City: Ocean State/Province: New Jersey Country: USA
Area of science: Medicine
ID: 1237263231.Me
Message:

how can blood flow back to the heart through the veins when someone is sitting
down or sleeping in bed, if there is no muscle contraction? the heart doesn't
suck the blood back in. If it did, then the veins would have equal blood
pressure to the arteries. the veins rely on muscle movements in order for the
blood to flow back to the heart. if there is no muscle contraction,  then the
blood would technically swell up in a person's legs and feet, and the heart
would therefore get less and less blood back. so how do the veins return the
blood to the heart if a person is sleeping and are not really moving their legs
or their arms while they are sleeping? or let's say a person is standing still.
how do the veins get the blood back to the heart against gravity?
thanks for your help.


Re: how can blood flow back to the heart through the veins when someone is sitt

Current Queue | Current Queue for Medicine | Medicine archives

Try the links in the MadSci Library for more information on Medicine.



MadSci Home | Information | Search | Random Knowledge Generator | MadSci Archives | Mad Library | MAD Labs | MAD FAQs | Ask a ? | Join Us! | Help Support MadSci


MadSci Network, webadmin@madsci.org
© 1995-2006. All rights reserved.