Intro to Vasculature Flashcards
major components of the cardiovascular system
- heart
- blood vessels
- blood
major function of cardiovascular system
transportation of nutrients and oxygen, waste products, and hormones
the atria are the ____ chambers
receiving
the ventricles are the ____ chambers
discharging
the left side of the heart is the pump for the ____ circuit
systemic
the left atrium received _____ blood
oxygenated
the right side of the heart is the pump for the _____ circuit
pulmonary
the right atrium receives _____ blood
deoxygenated
carry blood away from the heart
arteries
smallest of the blood vessels; have a thin wall; main role is to allow the exchange of materials between the blood and body tissues
capillaries
carry blood toward the heart
veins
arteries carry ____ blood in the systemic circulation and carry _____ blood in the pulmonary circulation
oxygenated; deoxygenated
the smallest artery is a ____
arteriole
veins carry ____ in the systemic circulation and ____ blood in the pulmonary circulation
deoxygenated blood; oxygenated
smallest vein is a ____
venule
heart and blood vessel pathway
heart, arteries, arterioles, capillaries, venules, veins, heart
the walls of blood vessels (except the smallest) have three layers or tunics:
- tunica interna or tunica intima
- tunica media
- tunica externa or tunica adventitia
3 parts to the tunica interna or tunica intima
a. endothelium
b. basal lamina
c. subendothelial layer
contains rings of smooth muscle cells responsible for vasoconstriction and vasodilation; can also contain sheets or lamellae or laminae of elastin
tunica media
in larger vessels this tunic contains a vasa vasorum and a nervi vascularis
tunica externa or tunica adventitia
in cross section, ____ will appear more open and ____ more collapsed; additionally, the lumen of the ____ is much larger than that of the comparable artery
arteries; veins
in arteries, the thickest layer is the _____
tunica media
in veins, the thickest layer is the ____
tunica externa
largest diameter arteries (diameter is greater than 10 mm)
elastic or conducting arteries (large arteries)
walls of large arteries contain large amounts of _____; allows arteries to expand and recoil; important vessels important in helping to propel blood onward while ____ are relaxing
elastic fibers; ventricles
elastic fibers function as _____
pressure reserve
medium-sized arteries have a diameter of ___ to ___ mm; walls contain large amounts of _____
2; 10; smooth muscle
medium sized arteries also called _____ or ____
muscular or distributing arteries
medium arteries are important in regulating blood flow to specific body regions; smooth muscle cells in _____ orientation and are responsible for _____ and _____
circular; vasoconstriction (reduction in lumen diameter); vasodilation (increase in lumen diameter)
diameter of small arteries
0.1 mm to 2 mm
small arteries have as many as ____ layers of smooth muscle in their _____
eight; tunica media
smallest diameter artery; only one or two layers of smooth muscle in the tunica media
arterioles
diameter of arterioles
10 to 100 micrometers
capillaries have the smallest diameter of all blood vessels which is _____
4-10 micrometers
capillaries have thin walls consisting of ____ and its _____
endothelial cell; basal lamina
main role of capillaries is to allow the exchange of materials between the ____ and _____
blood; body tissues
4 types of arteries:
- elastic or conducting (large arteries)
- muscular or distributing (medium arteries)
- small arteries
- arterioles
smallest diameter vein; 10-100 micrometer diameter; receive blood from capillaries
venules
endothelial cell with basal lamina and pericytes; no tunica media and no adventitia
postcapillary venule
possess a tunica media with one or two layers of smooth muscle and a thin tunica adventitia; typically no pericytes here
muscular venule
small veins:
0.1 mm to 1 mm in diameter; receive blood from muscular venule
medium veins
1mm to 10mm in diameter; all three layers present.
large veins
larger than 10mm in diameter; all three layers present.
most veins in limbs have ____ which prevent backflow of blood
valves
thin folds of tunica intima- endothelial cells over a thin layer of connective tissue
valves
thickest layer in arteries
tunica media
thickest layer in veins
tunica externa/tunica adventitia
Found between the internal elastic membrane and the external elastic membrane, when these membranes are present
tunica media
Composed of endothelium, basal lamina, and subendothelial connective tissue
tunica interna
Composed of smooth muscle cells and elastic sheets
tunica media
May contain a vasa vasorum and a nervi vascularis in larger vessels.
tunica externa/adventitia
