Cardiovascular System Key Terms

7th Grade Science

Cardiovascular System

• The body system that consists of the heart blood vessels and blood that carries needed substances to cells and carries waste products away from cells

Heart

• A hollow muscular organ that pumps blood throughout the body

Atrium

• Each of the two upper chambers of the heart that receives blood entering the heart

Ventricle

• A lower chamber of the heart that pumps blood out to the lungs and body

Valve

• A flap of tissue in the heart or a vein that prevents blood from flowing backwards

Pacemaker

• A group of cells located in the right atrium that send out signals that make the heart muscle contract and that regulates heart rate

Artery

• A blood vessel that carries blood away from the heart

Capillary

• A tiny blood vessel where substances are exchanged between the blood and body cells

Vein

• A blood vessel that carries blood back to the heart

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 blood against the walls of blood vessels

Diffusion

• The process by which molecules move from an area in which they are more concentrated to an 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 the lungs and delivers it to cells elsewhere in the body

Hemoglobin

• An iron containing protein that binds chemically to oxygen molecules and makes up most of a red blood cells

White blood cell

• A blood cell that fights disease

Platelet

• A cell fragment that plays an important part in forming clouts

Arteriosclerosis

• A condition in which an artery wall thickens as a result of a build up of fatty materials

Heart attack

• A condition in which blood flows to a part of the heart; the heart muscle is blocked which causes heart cells to die

Hypertension

• A disorder in which a person’s blood pressure is constantly higher than normal