Cardiovascular System Key Terms
7th Grade Science
Cardiovascular System
•The body system that consists of the heartblood vessels and blood that carries neededsubstances to cells and carries waste productsaway from cells
Heart
•A hollow muscular organ that pumps bloodthroughout the body
Atrium
•Each of the two upper chambers of the heartthat receives blood entering the heart
Ventricle
•A lower chamber of the heart that pumpsblood out to the lungs and body
Valve
•A flap of tissue in the heart or a vein thatprevents blood from flowing backwards
Pacemaker
•A group of cells located in the right atriumthat send out signals that make the heartmuscle contract and that regulates heart rate
Artery
•A blood vessel that carries blood away fromthe heart
Capillary
•A tiny blood vessel where substances areexchanged between the blood and body cells
Vein
•A blood vessel that carries blood back to theheart
Aorta
•The largest artery in the body
Coronary artery
•An artery that supplies blood to the heart
Blood pressure
•The pressure the is exerted by the bloodagainst the walls of blood vessels
Diffusion
•The process by which molecules move from anarea in which they are more concentrated toan area in which they are less concentrated
Plasma
•The liquid part of the blood
Red blood cells
•A cell in the blood that takes up oxygen in thelungs and delivers it to cells elsewhere in thebody
Hemoglobin
•An iron containing protein that bindschemically to oxygen molecules and makes upmost of a red blood cells
White blood cell
•A blood cell that fights disease
Platelet
•A cell fragment that plays an important part informing clouts
Arteriosclerosis
•A condition in which an artery wall thickens asa result of a build up of fatty materials
Heart attack
•A condition in which blood flows to a part ofthe heart; the heart muscle is blocked whichcauses heart cells to die
Hypertension
•A disorder in which a person’s blood pressureis constantly higher than normal