THE CIRCULATORY SYSTEM

• transports oxygen and nutrients

throughout the body

• carries away wastes

• made up of 3 parts: blood, heart, and

blood vessels.

• Nelson Science

1. Blood

• has four components:

– Red blood cells contain

hemoglobin - binds oxygen to be

transported in the body.

– White blood cells - fight infection

in the blood.

– Platelets - help blood clot.

– Plasma - protein-rich liquid that

carries the blood cells.

Flow of Oxygenated and Deoxygenated Blood

2. Heart

• three types of tissue• cardiac muscle, nerve, and

connective tissue. • cardiac muscle tissue -

contracts to move blood throughout the body

3. Blood Vessels

3 Types:

1. Arteries• carry blood away from heart• blood under high pressure, so walls are thick

2. Veins• carry blood towards heart• blood under lower pressure to walls thinner

3. Capillaries• tiny vessels with thin walls• diffusion of gases happens between blood and cells• O2 diffuses out of blood into cell, CO2 diffuses into blood

from cell

• Interaction of Circulatory System with Other Systems

Diseases of Circulatory System

• coronary artery disease – can lead to a

heart attack.

• plaque from fat, cholesterol, calcium

deposits builds up

• plaque can block arteries to heart, cause

a blood clot

• heart cells don’t get oxygen, tissue starts

to die

• symptoms: tiredness, dizziness, pain or

burning in chest or arms