Transcript Introduction to the Circulatory System

Introduction to the
Circulatory System
Where does blood go?
• Blood vessels carry blood to every part of
the body
• Blood carries oxygen and nutrients to all
the parts of the body
• Blood carries carbon dioxide and waste
away from the body
• Basic pathway…
Heart-arteries-capillaries-veins-heart
From blood to the body…
• Materials transfer from the blood to the
body in 2 ways:
– Diffusion
• When materials go from an area of high
concentration to an area of lower concentration
– Active Transport
• Requires energy because material moves from an
area of low concentration to an area of higher
concentration
Blood Vessels
• Arteries (carry Away from the heart)
• Veins (carry To the heart)
• Capillaries (Connect arteries and veins)
Arteries
• Carry blood away from the heart
• 3 Layers
– Connective Tissue
– Smooth Muscle
– Elastic Connective Tissue
• Aorta – major artery the supplies blood to
the body
Veins
• Carry blood back to the heart
• 3 layers
– Connective tissue
– Smooth muscle
– Elastic Connective Tissue
• Have one way valves that keep blood from
flowing backward
• Superior vena cava – blood from the head and
neck
• Inferior vena cava – blood from the abdomen
and lower body
Capillaries
• Connect arteries and veins
• Only one cell thick
• Diffusion of nutrients and wastes occurs
across this barrier