30.4 Blood Vessels and Transport

Arteries, veins, and capillaries transport blood to all parts of the body.

30.4 Blood Vessels and Transport

Arteries carry blood away from the heart.– blood under great pressure– thicker, more muscular walls

ARTERYVEIN

CAPILLARIES

arteriole venule

endothelium

connective tissue

smooth musclevalve

30.4 Blood Vessels and Transport

Veins carry blood back to the heart.

– blood under less pressure– thinner walls, larger diameter– valves prevent backflow

ARTERYVEIN

CAPILLARIES

arteriole venule

endothelium

connective tissue

smooth musclevalve

30.4 Blood Vessels and Transport

Capillaries move blood between veins, arteries, and cells.

ARTERYVEIN

CAPILLARIES

arteriole

endothelium

connective tissue

smooth muscle

venule

valve

30.4 Blood Vessels and Transport

Blood Components– plasma– red blood cells – white blood cells – platelets

red blood cells,white blood cells,and platelets

plasma

* Blood transports materials

30.4 Blood Vessels and Transport

Plasma

– 55% of Blood– molecules diffuse into

and out of it– contains proteins and

clotting factors– ~90 % water

30.4 Blood Vessels and Transport

Red blood cells

– transport oxygen to cells and carry away carbon dioxide– have no nuclei and contain hemoglobin

30.4 Blood Vessels and Transport

White Blood Cells

fight pathogens and destroy foreign matter.

red blood cell

platelet

white blood cell

30.4 Blood Vessels and Transport

Platelets

help form clots that control bleeding.

platelets

fibrin

red blood cell

white blood cell