circulatory system Flashcards
what is the main purpose of the circulatory system
The function of the circulatory system is to transport O2 and nutrients to body cells and to carry oxygen-poor blood and CO2 back to the heart and lungs.
which organs are in the circulatory system
- blood vessels
- heart
- blood
what is the function of blood vessels in the circulatory system
to deliver blood to the organs and tissues in your body.
what is the function of the heart in the circulatory system
the heart sends blood throughout our bodies, carrying oxygen to every cell
what is the function of blood in the circulatory system
blood carries carbon dioxide to the lungs (for exhalation) and picks up oxygen
compare arteries, veins and capillaries.
Arteries carry blood away from your heart. Veins carry blood back toward your heart. Capillaries, the smallest blood vessels, connect arteries and veins. They all transport blood around the body.
Describe how blood is moved through arteries, capillaries and veins
Blood flows in the same direction as the decreasing pressure gradient: arteries to capillaries to veins
Explain how valves help blood flow in one direction in veins
One-way valves consist of two flaps (cusps or leaflets) with edges that meet. These valves help veins return blood to the heart. As blood moves toward the heart, it pushes the flaps open
step 1 and 2 of blood flow through the heart
- The blood first enters the right atrium from the superior and inferior vena cava.
- It then flows through the tricuspid valve into the right ventricle
step 3 and 4 of blood flow through the heart
- The blood then moves through the pulmonary valve into the pulmonary artery.
- The pulmonary artery carries blood to the lungs where it takes up oxygen.
step 5 and 6 (left side) of blood flow through the heart
- Oxygenated blood returns to the heart through the pulmonary vein into the left atrium.
- The blood then moves through the mitral valve into the left ventricle.
step 7 (left side) of blood flow through the heart
- The left ventricle then pumps the blood through the aortic valve into the aorta.
step 8 (left side) of blood flow through the heart
- From the aorta, the blood is transported through the network of blood vessels, delivering oxygen and nutrients to tissues and taking carbon dioxide and wastes from tissues.
step 9 (left side) of blood flow through the heart
Deoxygenated blood returns to the heart via the superior and inferior vena cava, and the cycle begins again.
Explain how valves help blood flow in one direction
Blood passes through a valve before leaving each chamber of the heart. The valves prevent the backward flow of blood
