TAMU BIOL 320 TEST 2 EXAM 2025
QUESTIONS AND ANSWERS
In which specific structure is blood pressure highest? - ANS The aorta
Blood ____________ (leaving/entering) the heart is at its highest pressure. - ANS Leaving
What are the three layers of a blood vessel from most deep to most superficial? - ANS -
Tunica intima
- Tunica media
- Tunica externa
What type of tissue is tunica intima comprised of? - ANS Endothelial tissue
What type of cells is tunica media comprised of? - ANS Smooth muscle tissue
What type of cells is tunica externa comprised of? - ANS Collagen fibers
Which tunic is significantly smaller in a vein when compared to and artery? - ANS Tunica
media
What are the two layers of a capillary? - ANS Basement membrane and endothelial cells
What are the three types of arteries? - ANS - Elastic
- Muscular
- Arteriole
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,What are the two types of veins? - ANS Venule and veins
What are the functions of tunica externa? - ANS - Anchoring
- Protection
- House vaso vasorum
Define: Vaso vasorum - ANS Network of blood vessels that feel the blood vessels of the body;
micro circulatory system
What structure about veins prevents backflow? - ANS Valves
What are the major functions of elastic arteries? - ANS - Reduce shock
- EVEN OUT FLOW
T/F: Elastic and muscular arteries vasoconstrict while arterioles cannot vasoconstrict. -
ANS False: Muscular arteries and arterioles CAN vasoconstrict while elastic arteries CANNOT
vasoconstrict
What is the major function of muscular arteries? - ANS Limit flow of blood to less
important/nonessential tissues
What is the function of arterioles? - ANS To connect arteries to capillaries
How thick are capillary walls? - ANS 1 cell thick
Define: Thoroughfare (wrt capillaries) - ANS Structures that allow blood to pass through
closed capillary beds unhindered
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,What are the functions of pericytes? - ANS Stabilize the walls of capillary beds
What are the functions of precapillary sphincters? - ANS To constrict and dilate to open and
close capillary beds as needed
In what tissues can you find continuous capillary walls? - ANS Skin, muscle, and brain
What sort of permeability do continuous capillary walls have? - ANS Very restricted: Only
allow for select solutes and chemicals to move
What are the two subcategories of fenestrated capillaries? - ANS With and without a
diaphragm
In what tissues are fenestrated capillaries found? - ANS Intestine, kidneys, and endocrine
glands
Fenestrated capillaries allow for ____________ (a lot/very little) solute movement. - ANS A
lot
In what tissues are sinusoidal capillaries found? - ANS Tissues that are involved with blood:
Liver, marrow, spleen
Define: Fenestra - ANS Gaps within capillary walls that allow for the movement of solutes
and blood cells
List the capillary types in order from least to most leaky (include both types of fenestrated
capillaries). - ANS - Continuous
- Fenstrated w/ diaphragm
- Fenestrated w/out diaphragm
- Sinusoidal
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, What causes hemorrhoids and varicose veins? - ANS Ruptured vein valves
What % of blood exists in veins and venules? - ANS 60%
What % of blood exists in arteries and arterioles? - ANS 15%
What % of blood can be found in pulmonary blood vessels? - ANS 12%
What % of blood is found in the heart? - ANS 8%
Define: Blood flow - ANS Volume of blood passing through a *Defined area* at a *given
time*
Define: Blood pressure - ANS The amount of force exerted on a vessel wall
Define: Resistance - ANS Opposition to flow
What are the factors that play into resistance? - ANS - Viscosity
- Length of the vessel
- Vessel diameter
________ (longer/shorter) vessels INCREASE viscosity. - ANS Longer
Define: Laminar flow - ANS Relatively uniform flow of a liquid through a vessel
________ flow is responsible for the sounds of the heart. - ANS Turbulent
Blood flow is measured in ______. - ANS mL/min
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QUESTIONS AND ANSWERS
In which specific structure is blood pressure highest? - ANS The aorta
Blood ____________ (leaving/entering) the heart is at its highest pressure. - ANS Leaving
What are the three layers of a blood vessel from most deep to most superficial? - ANS -
Tunica intima
- Tunica media
- Tunica externa
What type of tissue is tunica intima comprised of? - ANS Endothelial tissue
What type of cells is tunica media comprised of? - ANS Smooth muscle tissue
What type of cells is tunica externa comprised of? - ANS Collagen fibers
Which tunic is significantly smaller in a vein when compared to and artery? - ANS Tunica
media
What are the two layers of a capillary? - ANS Basement membrane and endothelial cells
What are the three types of arteries? - ANS - Elastic
- Muscular
- Arteriole
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,What are the two types of veins? - ANS Venule and veins
What are the functions of tunica externa? - ANS - Anchoring
- Protection
- House vaso vasorum
Define: Vaso vasorum - ANS Network of blood vessels that feel the blood vessels of the body;
micro circulatory system
What structure about veins prevents backflow? - ANS Valves
What are the major functions of elastic arteries? - ANS - Reduce shock
- EVEN OUT FLOW
T/F: Elastic and muscular arteries vasoconstrict while arterioles cannot vasoconstrict. -
ANS False: Muscular arteries and arterioles CAN vasoconstrict while elastic arteries CANNOT
vasoconstrict
What is the major function of muscular arteries? - ANS Limit flow of blood to less
important/nonessential tissues
What is the function of arterioles? - ANS To connect arteries to capillaries
How thick are capillary walls? - ANS 1 cell thick
Define: Thoroughfare (wrt capillaries) - ANS Structures that allow blood to pass through
closed capillary beds unhindered
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,What are the functions of pericytes? - ANS Stabilize the walls of capillary beds
What are the functions of precapillary sphincters? - ANS To constrict and dilate to open and
close capillary beds as needed
In what tissues can you find continuous capillary walls? - ANS Skin, muscle, and brain
What sort of permeability do continuous capillary walls have? - ANS Very restricted: Only
allow for select solutes and chemicals to move
What are the two subcategories of fenestrated capillaries? - ANS With and without a
diaphragm
In what tissues are fenestrated capillaries found? - ANS Intestine, kidneys, and endocrine
glands
Fenestrated capillaries allow for ____________ (a lot/very little) solute movement. - ANS A
lot
In what tissues are sinusoidal capillaries found? - ANS Tissues that are involved with blood:
Liver, marrow, spleen
Define: Fenestra - ANS Gaps within capillary walls that allow for the movement of solutes
and blood cells
List the capillary types in order from least to most leaky (include both types of fenestrated
capillaries). - ANS - Continuous
- Fenstrated w/ diaphragm
- Fenestrated w/out diaphragm
- Sinusoidal
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, What causes hemorrhoids and varicose veins? - ANS Ruptured vein valves
What % of blood exists in veins and venules? - ANS 60%
What % of blood exists in arteries and arterioles? - ANS 15%
What % of blood can be found in pulmonary blood vessels? - ANS 12%
What % of blood is found in the heart? - ANS 8%
Define: Blood flow - ANS Volume of blood passing through a *Defined area* at a *given
time*
Define: Blood pressure - ANS The amount of force exerted on a vessel wall
Define: Resistance - ANS Opposition to flow
What are the factors that play into resistance? - ANS - Viscosity
- Length of the vessel
- Vessel diameter
________ (longer/shorter) vessels INCREASE viscosity. - ANS Longer
Define: Laminar flow - ANS Relatively uniform flow of a liquid through a vessel
________ flow is responsible for the sounds of the heart. - ANS Turbulent
Blood flow is measured in ______. - ANS mL/min
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