UTA A&P II CH. 21 BLOOD VESSELS &
HEMODYNAMICS EXAM QUESTIONS
AND ANSWERS 100% PASS 2026/2027
Venules - ANS Collect blood from capillaries
Largest Blood Vessels attach to heart - ANS Pulmonary trunk
Aorta
3 layers of vessel walls - ANS Tunica interna (intima)
Tunica media
Tunica externa
Tunica Interna- - ANS innermost layer, includes
Endothelial lining, direct contact with blood, continuous with endocardial lining of heart
Basement membrane, deep to endothelium- physical support for endothelial layer
Internal elastic membrane - ANS Arteries only- Layer of elastic fibers in outer margin
Openings, look like Swiss cheese- facilitate diffusion of materials through tunica interna to
tunica media
@2026 ALLRIGHTS RESERVED 1
,Tunica Media- - ANS middle layer
Contains concentric sheets of smooth muscle in loose connective tissue, regulates vessel
diameter
Contract- vasoconstriction, relax- vasodialation
Sympathetic stimulation- constricts
NO, H+, lactic acid- dilate
Thickest layer in artery
External elastic membrane- - ANS separates tunica media from tunica externa (arteries only)
Tunica Externa- - ANS outer layer
Connective tissue sheath- collagen & elastic fibers
Contains lots of nerves & vessels supply tissue of vessel (vasa vasorum)
Anchors vessel to adjacent tissues in arteries
In veins, thicker than tunica media, contains elastic fibers and smooth muscle cells
From heart to capillaries arteries change to: - ANS elastic arteries
To muscular arteries
To arterioles
Elastic Arteries - ANS (conducting arteries)
Largest vessels in body (pulmonary trunk and aorta)
Transport large volumes of blood
Characterized by well-defined internal & external elastic laminae
Push blood onward as ventricles relax, accommodate large surge of blood out of heart
@2026 ALLRIGHTS RESERVED 2
, Tunica media of elastic arteries - ANS thick, with many elastic fibers (elastic lamellae), few
muscle cells- absorb pressure, elastic rebound
Muscular Arteries- - ANS (distribution arteries)
Medium sized (most arteries)
Muscle lends ability to contract & maintain state of partial contraction- vascular tone
Vascular tone stiffens vessel wall, important in maintaining vessel pressure & efficient blood
flow
Tunica media of muscular arteries - ANS more smooth muscle, fewer elastic fibers than
elastic arteries
Capable of vasoconstriction & vasodilation to adjust rate of blood flow
Anastomoses - ANS Union of branches of two or more arteries supplying the same body
region
Provide alternative route for blood
Alternative route of blood flow through anastomosis-collateral circulation
End arteries- - ANS arteries that do not anastomose
Arterioles - ANS Abundant microscopic vessels that regulate blood flow into capillary
networks
Small, little or no tunica externa
Thin or incomplete tunica media
Thin tunica interna with a thin, fenestrated (small pores) internal elastic lamina that disappears
at the terminal end
@2026 ALLRIGHTS RESERVED 3
HEMODYNAMICS EXAM QUESTIONS
AND ANSWERS 100% PASS 2026/2027
Venules - ANS Collect blood from capillaries
Largest Blood Vessels attach to heart - ANS Pulmonary trunk
Aorta
3 layers of vessel walls - ANS Tunica interna (intima)
Tunica media
Tunica externa
Tunica Interna- - ANS innermost layer, includes
Endothelial lining, direct contact with blood, continuous with endocardial lining of heart
Basement membrane, deep to endothelium- physical support for endothelial layer
Internal elastic membrane - ANS Arteries only- Layer of elastic fibers in outer margin
Openings, look like Swiss cheese- facilitate diffusion of materials through tunica interna to
tunica media
@2026 ALLRIGHTS RESERVED 1
,Tunica Media- - ANS middle layer
Contains concentric sheets of smooth muscle in loose connective tissue, regulates vessel
diameter
Contract- vasoconstriction, relax- vasodialation
Sympathetic stimulation- constricts
NO, H+, lactic acid- dilate
Thickest layer in artery
External elastic membrane- - ANS separates tunica media from tunica externa (arteries only)
Tunica Externa- - ANS outer layer
Connective tissue sheath- collagen & elastic fibers
Contains lots of nerves & vessels supply tissue of vessel (vasa vasorum)
Anchors vessel to adjacent tissues in arteries
In veins, thicker than tunica media, contains elastic fibers and smooth muscle cells
From heart to capillaries arteries change to: - ANS elastic arteries
To muscular arteries
To arterioles
Elastic Arteries - ANS (conducting arteries)
Largest vessels in body (pulmonary trunk and aorta)
Transport large volumes of blood
Characterized by well-defined internal & external elastic laminae
Push blood onward as ventricles relax, accommodate large surge of blood out of heart
@2026 ALLRIGHTS RESERVED 2
, Tunica media of elastic arteries - ANS thick, with many elastic fibers (elastic lamellae), few
muscle cells- absorb pressure, elastic rebound
Muscular Arteries- - ANS (distribution arteries)
Medium sized (most arteries)
Muscle lends ability to contract & maintain state of partial contraction- vascular tone
Vascular tone stiffens vessel wall, important in maintaining vessel pressure & efficient blood
flow
Tunica media of muscular arteries - ANS more smooth muscle, fewer elastic fibers than
elastic arteries
Capable of vasoconstriction & vasodilation to adjust rate of blood flow
Anastomoses - ANS Union of branches of two or more arteries supplying the same body
region
Provide alternative route for blood
Alternative route of blood flow through anastomosis-collateral circulation
End arteries- - ANS arteries that do not anastomose
Arterioles - ANS Abundant microscopic vessels that regulate blood flow into capillary
networks
Small, little or no tunica externa
Thin or incomplete tunica media
Thin tunica interna with a thin, fenestrated (small pores) internal elastic lamina that disappears
at the terminal end
@2026 ALLRIGHTS RESERVED 3
