Sub 1: Cardiovascular System Flashcards
(44 cards)
what are the components of the cardiovascular system?
blood vessels and heart
name 3 types of blood vessel
arteries, capillaries, veins
what materials does the blood transport around the body?
oxygen to respiring cells carbon dioxide away from respiring cells digested food form digestive system to liver for storage urea from liver hormones antibodies heat
what are arteries?
arteries carry blood away from the heart
what features do arteries have and why?
they have thick elastic walls which stretch and recoil in response to the heartbeat, needs to be able to withstand pressure
elastic nature also turns a pulse of blood into a continuous flow
what is a capillary?
capillaries allow the exchange of materials to take place between blood and body cells
what features do capillaries have and why?
walls are one cell thick so materials can diffuse easily to and from the blood
have tiny diameter just wide enough to enable red blood cells to pass through
what are veins?
veins carry blood back to the heart
what features do veins have and why?
thinner less elastic walls, longer lumen than arteries since blood pressure is very low in veins
have valves which prevent the blood flowing backwards
what is blood pressure?
describes the pressure in the aorta
how is blood pressure measured?
using a sphygmomanometer and a stethoscope
what are the units of blood pressure?
mmHg
what is systolic blood pressure?
the pressure in the arteries when the heart contracts
what is diastolic blood pressure?
the pressure in the arteries when the heart relaxes
how is blood pressure written?
systolic/diastolic
what is normal blood pressure?
120/80 mmHG
what is the heart?
muscular pump that keeps blood flowing through the blood vessels
what does the right side of the heart do?
pumps blood to the lungs to be oxygenated
what does the left side of the heart do?
pumps blood around the body
what is the left and the right side of the heart separated by?
septum
what is myocardium?
made up of cardiac muscle. it has small interconnected cells that allow the rapid spread of electrical impulses that cause contractions
what initiates the impulses in the myocardium?
the sinoatrial node high in the right atrium
what is systole?
contraction of the heart muscle
what is diastole?
relaxation of the heart muscle