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chamberlain BIOS 255 CHAPTER 21 Exam
Questions and Answers 100% Pass
tunica interna (intima) - ANSWER ✔✔-the innermost layer of a blood vessel, closest to lumen, direct
contact with blood. consist of inner endothelium and basement membrane.
tunica media - ANSWER ✔✔-The middle and thickest layer of tissue of a blood vessel wall, composed of
elastic tissue and smooth muscle cells that allow the vessel to expand or contract in response to changes
in blood pressure and tissue demand.
tunica externa - ANSWER ✔✔-outer layer of a blood vessel which connects it to surrounding tissues and
forms protective layer.
Arteries - ANSWER ✔✔-carry blood away from the heart
functional properties of arteries - ANSWER ✔✔-elasticity- elastic tissue in tunica internal and media,
allows arteries to accept blood under pressure from contraction of ventricles
contractility- smooth muscle in tunica media, allows arteries to increase or decrease lumen size and limit
bleeding from wounds.
anastomoses - ANSWER ✔✔-anastomoses is the union of all pathways
- provide alternate route for blood flow arteries that do not anastomoses are know as end arterties.
- if end artery particular region of body and narcosis can occur.
type of arteries - ANSWER ✔✔-Elastic arteries( conducting arteries)
- Large diameter, more elastic fibers, less smooth muscle, function as pressure reservoirs
Created by Grace Amelia © 2025, All Rights Reserved.
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Muscular arteries ( distributing arteries)
- Medium diameter, more smooth muscle, fewer elastic fibers, distribute blood to various of body.
Capillaries - ANSWER ✔✔-capillaries are microscopic vessels that connect arterioles and venules.
the primary function is the exchange of nutrients and wastes between the blood and tissue cells through
interstitial fluid.
composed of a single layer( endothelium) cells and a basement membrane.
three type of capillaries - ANSWER ✔✔-continuous - layered in the endothelium cell. located in fat
muscle, and nervous system.
fenestrated - holes for nutrients and gases to pass. located in endocrine glands, kidneys, glomeruli
sinusoids - incomplete basement membrane. located in the liver, bone marrow, spleen
venules - ANSWER ✔✔-smallest veins
small vessels that are formed by the union of several capillaries drain capillaries into veins
veins - ANSWER ✔✔-veins have thinner tunica interna and media and thicker tunica externa
veins have less elastic tissue and less smooth muscles than arteries
veins contain valve and weak valve can lead to varicose veins
blood distribution - ANSWER ✔✔-largest portion of blood is in systematic veins and venules which are
called blood reservoirs. principles reservoirs are the veins of the abdominal organs ( inner spleen) and
skin.
reabsorption ( in bulk flow) - ANSWER ✔✔-reabsorption is a pressure-driven movement of fluid and
solutes from the interstitial fluid into blood capillaries
interstitial fluid hydrostatic pressure (IFHP) and blood colloid osmotic pressure promote reabsorption
Created by Grace Amelia © 2025, All Rights Reserved.
chamberlain BIOS 255 CHAPTER 21 Exam
Questions and Answers 100% Pass
tunica interna (intima) - ANSWER ✔✔-the innermost layer of a blood vessel, closest to lumen, direct
contact with blood. consist of inner endothelium and basement membrane.
tunica media - ANSWER ✔✔-The middle and thickest layer of tissue of a blood vessel wall, composed of
elastic tissue and smooth muscle cells that allow the vessel to expand or contract in response to changes
in blood pressure and tissue demand.
tunica externa - ANSWER ✔✔-outer layer of a blood vessel which connects it to surrounding tissues and
forms protective layer.
Arteries - ANSWER ✔✔-carry blood away from the heart
functional properties of arteries - ANSWER ✔✔-elasticity- elastic tissue in tunica internal and media,
allows arteries to accept blood under pressure from contraction of ventricles
contractility- smooth muscle in tunica media, allows arteries to increase or decrease lumen size and limit
bleeding from wounds.
anastomoses - ANSWER ✔✔-anastomoses is the union of all pathways
- provide alternate route for blood flow arteries that do not anastomoses are know as end arterties.
- if end artery particular region of body and narcosis can occur.
type of arteries - ANSWER ✔✔-Elastic arteries( conducting arteries)
- Large diameter, more elastic fibers, less smooth muscle, function as pressure reservoirs
Created by Grace Amelia © 2025, All Rights Reserved.
, 2|Page
Muscular arteries ( distributing arteries)
- Medium diameter, more smooth muscle, fewer elastic fibers, distribute blood to various of body.
Capillaries - ANSWER ✔✔-capillaries are microscopic vessels that connect arterioles and venules.
the primary function is the exchange of nutrients and wastes between the blood and tissue cells through
interstitial fluid.
composed of a single layer( endothelium) cells and a basement membrane.
three type of capillaries - ANSWER ✔✔-continuous - layered in the endothelium cell. located in fat
muscle, and nervous system.
fenestrated - holes for nutrients and gases to pass. located in endocrine glands, kidneys, glomeruli
sinusoids - incomplete basement membrane. located in the liver, bone marrow, spleen
venules - ANSWER ✔✔-smallest veins
small vessels that are formed by the union of several capillaries drain capillaries into veins
veins - ANSWER ✔✔-veins have thinner tunica interna and media and thicker tunica externa
veins have less elastic tissue and less smooth muscles than arteries
veins contain valve and weak valve can lead to varicose veins
blood distribution - ANSWER ✔✔-largest portion of blood is in systematic veins and venules which are
called blood reservoirs. principles reservoirs are the veins of the abdominal organs ( inner spleen) and
skin.
reabsorption ( in bulk flow) - ANSWER ✔✔-reabsorption is a pressure-driven movement of fluid and
solutes from the interstitial fluid into blood capillaries
interstitial fluid hydrostatic pressure (IFHP) and blood colloid osmotic pressure promote reabsorption
Created by Grace Amelia © 2025, All Rights Reserved.
