The heart is a four-chambered
organ with four main vessels, which either bring
blood to or carry blood away from the heart.
The four chambers of the heart are the right
atrium, right ventricle, left atrium, and left
ventricle.
The great vessels of the heart include:
- Superior
and inferior vena cava (brings blood from the
body to the right atrium)
- Pulmonary artery
(transports blood from the right ventricle
to the lungs)
- Aorta (the body’s
largest artery, which transports oxygen-rich
blood from the left ventricle to the rest of
the body)
A series of one-way valves keep the
blood flowing in one direction with every
heartbeat. Blood first enters the heart into
the right atrium then passes from the right
atrium through the tricuspid valve and into
the right ventricle. When the right ventricle
contracts, the muscular force pushes blood
through the pulmonary semilunar valve into
the pulmonary artery. Blood then travels to
the lungs, where it receives oxygen.
Next,
it drains out of the lungs via the pulmonary
veins, and travels to the left atrium.
From the left atrium, the blood is forced through
the bicuspid valve into the left ventricle.
The left ventricle is the major muscular
pump that sends the blood out to the body
systems. When the left ventricle contracts, it
forces the blood through the aortic semilunar
valves and into the aorta. The aorta and its
branches carry blood to all the tissues of the
body.
|
A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation
HealthCare Commission (www.urac.org). URAC's accreditation
program is the first of
its kind, requiring compliance with 53 standards of quality and accountability,
verified by independent audit. A.D.A.M. is among the first to achieve this important
distinction for online health information and services. Learn more about A.D.A.M.'s editorial
process. A.D.A.M. is also a
founding member of Hi-Ethics (www.hiethics.com) and subscribes to the principles
of the Health on the Net Foundation (www.hon.ch).
©Copyright 2005 A.D.A.M., Inc. Any duplication or distribution of the
information contained herein is strictly prohibited.
The information provided herein should not be used during any
medical emergency or for the diagnosis or treatment of any medical condition.
A licensed physician should be consulted for diagnosis and treatment of any
and all medical conditions. Call 911 for all medical emergencies. Links to
other sites are provided for information only -- they do not constitute endorsements
of those other sites.
|
