Chapter 42: Circulation. By Lauren Shevchek and Nonye Enogwe. Circulation…. t he continuous motion by which blood travels through all parts of the body under the action of the heart Helps with the transportation of blood throughout the body Regulates the .
By Lauren Shevchek
the continuous motion by which blood travels through all parts of the body under the action of the heart
-Circulatory fluid (blood)
-Set of tubes (blood vessels)
-Muscular pump (heart)
Amphibians have a three-chambered heart and two circuits of blood flow: pulmocutaneousand systemic. With double circulation, blood is delivered to systemic organs under high pressure. There is some mixing of oxygen-rich and oxygen-poor blood within the single ventricle.
Mammals have a four-chambered heart and double circulation. Inside of the heart, oxygen-rich blood is kept separated from oxygen-poor blood.
Fish have a two-chambered heart and a single circuit of blood flow
Advantages over single circulation
the alternating contractions and relaxations of the heart
Main two factors
an abnormal sound of the heart; sometimes a sign of abnormal function of the heart valves
a small body of specialized muscle tissue located in the wall of the right atrium of the heart that acts as a pacemaker by producing a contractile signal at regular intervals