ARTERIES, CAPILLARIES, VEINS Flashcards
What are the three blood vessels in the body?
Capillaries, arteries, veins (CAV)
What do the capillaries do?
Bring blood close to every cell in organs so substances (nutrients/O2)can diffuse between the blood in the capillary and the cells
What do the arteries do?
Carries oxygenated blood away from the heart to the body except for the pulmonary and umbilical artery
What do the veins do?
Carries oxygenated blood from the body to the the lungs except the pulmonary and umbilical vein
Give one way the capillaries are adapted for their function
VERY SMALL LUMEN which increases their surface area for diffusion
Give another way that the capillaries are adapted for their function
The walls of capillaries are ONE CELL THICK which shortens the diffusion distance between the blood in the capillaries to the cells
Which blood vessel has a higher pressure of blood?
Arteries, pumped out at high pressures by the ventricles because they have to reach the body’s tissue’s (aorta)
How are the arteries adapted for their function?
THICK LAYER OF MUSCLES WITH ELASTIC FIBRES to with stand the high pressure of blood ejected from the heart pushing the blood out
How else are the arteries adapted for their function?
SMALL LUMEN,ensure pressure is maintained
Is the pressure of blood high or low in the veins?
Veins carry deoxygenated blood back from the body, pressure of this blood much lower
How are the veins adapted for their function?
THIN LAYER OF MUSCLES WITH ELASTIC FIBRES for the low pressure in the veins
How else are the veins adapted for their function?
LARGE LUMEN allows more blood to flow with less VESSEL resistance
How else are the veins specifically adapted for their function?
They have VALVES prevent the back flow of blood
=as it is under low pressure/keeps blood flowing in the right direction
