Biology Ch 4
Name the four main components of blood.
red blood cells, white blood cells, plasma, platelets
What is the function of platelets?
form blood clots – prevent the loss of blood and stop
wounds becoming infected
What is the function of the red blood cells?
Bind to oxygen and transport it around the body
What is the function of the white blood cells?
Defend the body against pathogens
What is the function of the plasma?
Transports blood cells and substances around the body
How does the structure of an artery relate to its
function?
carries blood away from the heart under high pressure –
has a small lumen and thick, elasticated walls that can
stretch
How does the structure of a vein relate to
its function?
carries blood back to the heart at low pressure –doesn’t
need thick, elasticated walls, but has valves to prevent
blood fowing the wrong way
How does the structure of a capillary relate to its
function?
carries blood to cells and tissues – has a one-cell-thick
wall to provide a short di昀昀usion distance