BIO 431- EXAM 4- BLOOD VESSELS
& ANATOMY QUESTIONS WITH
COMPLETE ANSWERS
Compare/contrast arteries and veins in the terms of the following: Proportionally,
which have more smooth muscle cell (SMC) thickness, and tunica adventitia. -
ANSWER-Arteries
Which (arteries or veins) has: better elastic recoil - ANSWER-arteries
Which (arteries or veins) has: larger lumens - ANSWER-veins
Which (arteries or veins) has: higher pressures - ANSWER-arteries
Which (arteries or veins) has: a fixed capacitance - ANSWER-arteries
Which (arteries or veins) has: more compliance - ANSWER-veins
Which have pre-capillary sphincters? - ANSWER-arterioles
How many layers (tunics) do large arteries and veins have? 1,2 or 3? - ANSWER-3
How many layers do arterioles have? - ANSWER-2
How many layers do capillaries have? - ANSWER-1
How many layers do veins have? - ANSWER-3
Which have the highest elastin levels for the pressure reservoir function? -
ANSWER-Elastic arteries
Why are arterioles called your "resistance vessels"? - ANSWER-An arteriole is a
very small branch of an artery that delivers blood to a capillary. Through
vasoconstriction and vasodilation arterioles play major roles in: regulating blood flow
from arteries to capillaries, regulating blood pressure. Arterioles are therefore known
as resistance vessels.
How does NO (nitric oxide) affect arteriolar resistance? - ANSWER-Nitric oxide is
produced in response to high blood flow or other signaling molecules, and promotes
systemic and localized vasodilation.
How are veins modified to help maintain venous return under low pressure? -
ANSWER-Large lumens, valves, skeletal muscle pump,respiratory pump.
, Discuss venous valves - ANSWER-Veins have valves. Prevent backwards flow of
blood
Discuss the skeletal muscle pump - ANSWER-The valves in conjunction with
skeletal muscle pump, help accomplish venous return.
Discuss the respiratory pump - ANSWER-Lies horizontal. Elimante hydrostatic
pressure. Inspiration increase thoracic volume, decrease pressure in chest veins.
(pump)
Discuss the fact that veins have large lumens - ANSWER-Compared to arteries
veins have very large lumens. There are more layers with decreased R to blood flow.
Continous capillary - ANSWER-Most common and allow passage of fluids and small
solutes, least leaky, in skin and muscles.
Fenestrated capillary - ANSWER-more permeable to fluids and solutes, in kidney
filter plasma, in intestines absorb food. Endocrine glands.
Sinusoidal capillary - ANSWER-Whole cells can cross capillary wall. Bone marrow,
lymph tissue.
How do capillary hydrostatic pressure and blood colloid osmotic pressure (oncotic
pressure) affect fluid exchange in the capillary? - ANSWER-Hydrostatic pressure
forces fluid out of the capillary. Colloid osmotic pressure within the capillary pulls
fluids into the capillary.
What role does DIFFUSION play in metabolite (nutrients, blood gases) exchange? -
ANSWER-Metabolite exchange depends on diffusion. O2 and nutrients diffuse OUT.
NO net diffusion. CO2 and waste diffuse IN.
Is there a NET fluid filtration or NET fluid reabsorption on the arterial side of the
capillary bed? - ANSWER-net fluid filtration
What occurs at the capillary midsection? - ANSWER-No net diffusion
On the venous side? - ANSWER-net fluid reabsorption
Hydrostatic pressure - ANSWER-In the vertical plane. Pressure against gravity. Ah2-
h1.
Transmural Pressure - ANSWER-Pressure difference across vessel wall.
Ptrans=P(in)-P(out) Baroreceptors can detect changes in Ptrans located in the
cartoid sinus, aortic arch. Located inside the vessel wall.
Driving pressure - ANSWER-Along the axis of the vessel. Its the pressure gradient
that determines flow.
& ANATOMY QUESTIONS WITH
COMPLETE ANSWERS
Compare/contrast arteries and veins in the terms of the following: Proportionally,
which have more smooth muscle cell (SMC) thickness, and tunica adventitia. -
ANSWER-Arteries
Which (arteries or veins) has: better elastic recoil - ANSWER-arteries
Which (arteries or veins) has: larger lumens - ANSWER-veins
Which (arteries or veins) has: higher pressures - ANSWER-arteries
Which (arteries or veins) has: a fixed capacitance - ANSWER-arteries
Which (arteries or veins) has: more compliance - ANSWER-veins
Which have pre-capillary sphincters? - ANSWER-arterioles
How many layers (tunics) do large arteries and veins have? 1,2 or 3? - ANSWER-3
How many layers do arterioles have? - ANSWER-2
How many layers do capillaries have? - ANSWER-1
How many layers do veins have? - ANSWER-3
Which have the highest elastin levels for the pressure reservoir function? -
ANSWER-Elastic arteries
Why are arterioles called your "resistance vessels"? - ANSWER-An arteriole is a
very small branch of an artery that delivers blood to a capillary. Through
vasoconstriction and vasodilation arterioles play major roles in: regulating blood flow
from arteries to capillaries, regulating blood pressure. Arterioles are therefore known
as resistance vessels.
How does NO (nitric oxide) affect arteriolar resistance? - ANSWER-Nitric oxide is
produced in response to high blood flow or other signaling molecules, and promotes
systemic and localized vasodilation.
How are veins modified to help maintain venous return under low pressure? -
ANSWER-Large lumens, valves, skeletal muscle pump,respiratory pump.
, Discuss venous valves - ANSWER-Veins have valves. Prevent backwards flow of
blood
Discuss the skeletal muscle pump - ANSWER-The valves in conjunction with
skeletal muscle pump, help accomplish venous return.
Discuss the respiratory pump - ANSWER-Lies horizontal. Elimante hydrostatic
pressure. Inspiration increase thoracic volume, decrease pressure in chest veins.
(pump)
Discuss the fact that veins have large lumens - ANSWER-Compared to arteries
veins have very large lumens. There are more layers with decreased R to blood flow.
Continous capillary - ANSWER-Most common and allow passage of fluids and small
solutes, least leaky, in skin and muscles.
Fenestrated capillary - ANSWER-more permeable to fluids and solutes, in kidney
filter plasma, in intestines absorb food. Endocrine glands.
Sinusoidal capillary - ANSWER-Whole cells can cross capillary wall. Bone marrow,
lymph tissue.
How do capillary hydrostatic pressure and blood colloid osmotic pressure (oncotic
pressure) affect fluid exchange in the capillary? - ANSWER-Hydrostatic pressure
forces fluid out of the capillary. Colloid osmotic pressure within the capillary pulls
fluids into the capillary.
What role does DIFFUSION play in metabolite (nutrients, blood gases) exchange? -
ANSWER-Metabolite exchange depends on diffusion. O2 and nutrients diffuse OUT.
NO net diffusion. CO2 and waste diffuse IN.
Is there a NET fluid filtration or NET fluid reabsorption on the arterial side of the
capillary bed? - ANSWER-net fluid filtration
What occurs at the capillary midsection? - ANSWER-No net diffusion
On the venous side? - ANSWER-net fluid reabsorption
Hydrostatic pressure - ANSWER-In the vertical plane. Pressure against gravity. Ah2-
h1.
Transmural Pressure - ANSWER-Pressure difference across vessel wall.
Ptrans=P(in)-P(out) Baroreceptors can detect changes in Ptrans located in the
cartoid sinus, aortic arch. Located inside the vessel wall.
Driving pressure - ANSWER-Along the axis of the vessel. Its the pressure gradient
that determines flow.
