Notes 14-1

The Circulatory System

Functions of blood

• Delivery and transportation of needed materials, such as oxygen and glucose

• Removal of waste products such as carbon dioxide

• Fighting diseases

The Heart• The heart is a hollow,

muscular organ that pumps blood throughout the body. The right side of the heart is completely separated from the left side by a wall of tissue called the septum. Each side has an upper chamber, or atrium, and a lower chamber, or ventricle.

Let’s Label the parts of the heart!

The Heart• As blood flows out of the heart and toward

the lungs, it passes through a valve like the one here.

• These valves only open one way and are designed to prevent backflow

Can you see all 4 chambers?

Two Loops• Blood circulates through

the body in two loops, with the heart at the center. In the first loop, blood travels from the heart to the lungs and then back to the heart. In the second loop, blood is pumped from the heart throughout the body and then returns to the heart.

Blood Pressure

• Blood exerts a force called blood pressure against the walls of the blood vessels

• Blood pressure is caused by ventricle contractions

• Blood in the arteries has the highest pressure, and pressure decreases as it moves away from the heart

Heart diseases

• Atherosclerosis• Heart attack• Hypertension• Stroke

• Let’s watch a heart transplant!• http://youtu.be/SyPjhHn7Q-o