Cardiovascular System Blood Vessels Flashcards
3 types of blood vessels in the body
arteries, veins, capillaries
what are arteries
large blood vessels that carry blood away from the heart. Lined with connective tissue, muscle tissue, and elastic fibers, with an innermost layer of epithelial cells
endothelium
the innermost lining of blood vessels
what do endothelial cells do?
secrete factors that affect the size of blood vessels, reduce blood clotting and promote the growth of blood vessels
arterioles
smaller branches of arteries. Thinner than arteries and carry the blood to capillaries
capillaries
delicate, microscopic vessels carry nutrient-rich, oxygenated blood from the arteries and arterioles to the body cells through their very thin walls
venules
small vein
once nutrient-rich, oxygenated blood gets to the cell, what happens?
nutrients are burned in the presence of oxygen (catabolism) to release energy
what happens to the waste products?
pass out of cells and into the thin-walled capillaries and the waste-filled blood flows back to the heart in small venules
veins
They conduct blood (that has given up most of its oxygen) toward the heart from the tissues.
valves
prevent the backflow of blood and keep the blood moving in one direction
what color is blood?
bright red in arteries (contains oxygen)
dark red in veins (contains carbon dioxide)
From the outside of the body, blood in veins appears blue because the color reflects off the skin
function of arteries
carry blood away from the heart
strong, thick elastic walls
blood pressure is high
carry oxygen-rich blood to tissues
characteristics of veins
carry blood back to the heart
thin walls with valves
blood pressure is low
carry oxygen-poor blood from tissues
pathway of the circulation of blood
heart, arteries, arterioles, tissue capillaries, venules, veins, heart
