Circulatory+System-+Period3+2010


 * Michelle, Brittany, Rachel, And Maria

Functions of a Circulatory System
 * Carry oxygen from lungs to tissues and carbon dioxide from tissues to lungs thereby aiding in the exchange of gases. Supply of oxygen is needed for proper functioning of the cells. Removal of carbon dioxide is also equally essential s it becomes toxic to cells when present in high amount.
 * Help in fighting against infections by the defense cells- the granulocytes and a granulocytes
 * Prevent over bleeding by forming blood clot by the platelets.
 * Helps to maintain pH of the blood by buffering system present

Oxygen binds with the respiratory pigment hemoglobin (Hb) at the lungs where the concentrated of O2 is high and is carried along in the bloodstream; until it reaches the capillaries where the concentration of O2 is low, where the O2 is unloaded.

Pulmonary carries blood between the heart and lungs. Deoxygenated blood levels the right ventricles by the pulmonary artery. Systemic starts at the left ventricle and ends at the atrium oxygenated blood to the rest of the body

heart rate is controlled by hormones as well as the autonomous nervous system adrenaline, a hormone increases heart valve while the sympathetic nervous system decreases heart rate

blood pressure, a force exerted by cirrculation blood blood pressure can change by eaither the heart moving more blood or by constricting or dialating blood vessels or added or removing fluid.

__**Major Parts of the heart:**__ media type="youtube" key="2RFVNjj8J3g" height="344" width="425" align="right" 1.) //__Ventricles__// ( lower chambers ) a.) **//__left ventricle__//** - pumps blood to the entire body, so its muscles are thicker than those of the right ventricle which pumps blood to the lungs. b.) //__**right ventricle**__// Receives blood from the right atrium and pumps it to the main pulmonary arteries.

2.) //__atrium -__// ( upper chamber ) a.) //__**right atrium**__// - ( upper chamber ) The right atrium receives deoxygenated blood from the body through the vena cana and pumps it into the right ventricle which then sends it to the lungs to be oxygenated b.) //__**left atrium** -__// receives oxygenated blood from the lungs and pumps it down into the left ventricle which delivers it to the body.

3.) __valves__ - located between the atria and themedia type="youtube" key="D3ZDJgFDdk0" height="344" width="425" align="right" ventricles of the heart called **__atrioventricular__** and two are located in the major vessles leaving the vavles called semilunar valves.**__//The left semilunar//__** is called aortic valve located int he aorta and the //**__right semilunar__**// valve is in the pulmonic and lies in pulmonary artery. //**__left atrioventricular__**// valve is know as a bicuspid valve. **The //__right atrioventricular__//** is called the tricuspid vavle. 4.) __major arteries__ a.) **__aorta__** - at the top of the heart, it is the main (and largest) artery of the circulatory system. It carries the blood out of the heart from the left ventricle b.) **__pulmonary artery__** - transport deoxygenated blood to the left and right lungs

__**4 fun facts**__
 * arteries carry blood away from the heart, where as veins carry blood toward the heart.
 * the heart beats about 3 billion times during an average lifetime
 * most of your blood is a colorless liquid called plasma
 * the body of an adult contains over 6,000 miles of blood vessels