Blood Vessels and The Parts of Blood

Three Types of Blood Vessels

• Arteries• Capillaries• Veins

Arteries

• Carry blood AWAY from the heart• Walls are thick- must be able to handle

PRESSURE of blood from the heartComposed of 3 layers:

Connective Tissue

Smooth Muscle

Epithelial Cells

Capillaries

• Exchange materials between the blood and the body cells (oxygen, carbon dioxide, etc.)

• Single layer of epithelial cells to allow for easy exchange

Veins• Carry blood BACK to the heart• 3 things help blood move through veins:– Contraction of skeletal muscles– Breathing– Valves

• Same structure as an artery (but not as thick)Composed of 3 layers:

Connective Tissue

Smooth Muscle

Epithelial Cells

Parts of the Blood

• Plasma• Red Blood Cells• White Blood Cells• Platelets

Plasma

• Liquid part of the blood• 90% water

Red Blood Cells

• Take up oxygen in the lungs and deliver it to the body

• Made mostly of HEMOGLOBIN– Binds chemically to the oxygen

White Blood Cells

• Disease fighters• Live fro months or even years

Platelets

• Cell fragments, work to form blood clots• Produces fibrin:– Chemical that weaves a net of fibers on a cut– Net catches blood cells which build up into a

blood clot