Chapter 12 Section 1

Question 0

Heart

Answer 0

A hollow, muscular organ that pumps blood throughout the body.

Question 1

cardiovascular system

Answer 1

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

Question 2

Atrium

Answer 2

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

Question 3

Ventricle

Answer 3

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

Question 4

Valve

Answer 4

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

Question 5

Pacemaker

Answer 5

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

Question 6

Artery

Answer 6

A blood vessel that carries blood away from the heart.

Question 7

Capillary

Answer 7

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

Question 8

Vein

Answer 8

A blood vessel that carries blood back to the heart.

Question 9

Aorta

Answer 9

The largest artery in the body.