Transcript Circulatory System

Circulatory System
What’s the Function of the
Cardiovascular System?
• Carries needed substances to cells
• Carries waste products away from
cells
Blood Vessels: Arteries
• Arteries: large thick walled muscular
elastic vessels that carry oxygenated blood
away from the heart.
• Blood is under pressure pushed through by
heart pumping.
• Arteries branch off from heart divide into
smaller vessels called arterioles.
• Arterioles enter tissues where they branch
in capillaries.
Capillaries
• Microscopic blood
vessels.
• Walls are one celled
thick
• Blood cells move
through in single file
line.
• Capillary walls enable
nutrients and gases to
diffuse easily between
blood cells and
surrounding tissue
cells.
Veins
• Veins: large blood vessels that carry
blood from tissues back toward the
heart.
• Blood is not under pressure.
• Veins in arms and legs have valves
that prevent blood from flowing
backward.
Your Heart
• Main function of the heart is to keep
blood moving constantly throughout
the body.
• Large organ made of cardiac muscle
that are rich with mitochondria
• Mammalian hearts have four
chambers.
– atria
– ventricles