blood vessels

Question 1

Blood Vessels

Answer 1

Closed circulatory system
Arteries
Arterioles
Veins
Venules
Capillaries
3 tunics
lumen

Question 2

Distribution of blood
Exchange of materials with tissues
Return of blood back to the heart

Answer 2

Blood Vessels

Question 3

Structures:
Most have same basic structure
- 3 layers surrounding the lumen

Answer 3

Blood Vessels

Question 4

Arteries and Veins are composed of 3 tunics

Tunica interna (intima)
Tunica media
Tunica externa

Answer 4

Tunica interna (intima)
Tunica media
Tunica externa

Question 5

Modifications account for 5 types of blood vessels and their structural/ functional differences

Answer 5

arteries,
arterioles;
the capillaries,
the venules;
the veins,

Question 6

Capillaries are composed of ________

Answer 6

endothelium

Question 7

Inner lining in direct contact with blood

Endothelium continuous with endocardial lining of heart

Active role in vessel-related activities

Presents in all vessels

Answer 7

Tunica interna (intima)

Question 8

Muscular and connective tissue layer – Elastin

Greatest variation among vessel types

Layer of smooth muscle regulates diameter of lumen

Supplied by sympathetic division of ANS

Answer 8

Tunica media

Question 9

Elastic and collagen fibers
Vasa vasorum
Helps anchor vessel to surrounding tissue

Answer 9

Tunica externa

Question 10

Types of Vessels:

Answer 10

Arteries – carry blood AWAY from the heart
Arterioles
Capillaries – site of exchange
Venules
Veins – carry blood TO the heart

Question 11

to deliver nutrients and oxygen to arterial and venous walls and to remove “waste” products, either produced by cells in the wall or introduced by diffusional transport through the endothelium of the artery or vein

Answer 11

vasa vasorum

Question 12

CLASSIFICATION OF ARTEIES:

Answer 12

Elastic
Muscular
Arterioles

Question 13

Aorta & its Major branches

Answer 13

Elastic

Question 14

Renal, Testicular, Radial, Tibial etc

Answer 14

Muscular

Question 15

<0.1 mm

Terminal arterioles
Meta-arterioles
Thoroughfare
channel/ preferred

Answer 15

Arterioles

Question 16

Largest arteries
Largest diameter but walls relatively thin
Function as pressure reservoir

Help propel blood forward while ventricles relaxing

Answer 16

Elastic Arteries

Question 17

Also known as conducting arteries – conduct blood to medium-sized arteries

Answer 17

Elastic Arteries

Question 18

Tunica media contains more smooth muscle and fewer elastic fibers than elastic arteries

Walls relatively thick

Capable of great vasoconstriction/ vasodilatation to adjust rate of blood flow

Answer 18

Muscular arteries

Question 19

Also called distributing arteries

Answer 19

Muscular arteries

Question 20

Union of the branches of 2 or more arteries supplying the same body region
Provide alternate routes – collateral circulation

Answer 20

Anastomoses

Question 21

Abundant microscopic vessels

Answer 21

Arterioles

Question 22

_________has precapillary sphincter which monitors blood flow into capillary

Answer 22

Metarteriole

Question 23

Sympathetic innervation and local chemical mediators can alter diameter and thus blood flow and resistance

Resistance vessels – resistance is opposition to blood flow

Vasoconstriction can raise blood pressure

Answer 23

Arterioles

Question 24

Smallest blood vessels connect arterial outflow and venous return

Answer 24

Capillaries

Question 25

flow from metarteriole through capillaries and into postcapillary venule

Answer 25

Microcirculation

Question 26

primary function is exchange between blood and interstitial fluid

Answer 26

Exchange vessels

Question 27

Lack tunica media and tunica externa Substances pass through just one layer of endothelial cells and basement membrane

Answer 27

Capillaries

Question 28

arise from single metarteriole

Answer 28

Capillary beds

Question 29

intermittent contraction and relaxation

Answer 29

Vasomotion

Question 30

bypasses capillary bed

Answer 30

Throughfare channel

Question 31

Types of Capillaries:

Answer 31

1. Continuous 2. Fenestrated 3. Sinusoids

Question 32

Endothelial cell membranes from continuous tube

Answer 32

Continuous capillaries

Question 33

Have fenestrations or pores

Answer 33

Fenestrated capillaries

Question 34

Wider and more winding Unusually large fenestrations

Answer 34

Sinusoids capillaries

Question 35

Large irregular vascular space (30-40 micron) eg.Liver, Spleen, Bone marrow, suprarenal, Parathyroid etc

Answer 35

SINUSOIDS

Question 36

Structural changes not as distinct as in arteries In general, very thin walls in relation to total diameter

Answer 36

Veins

Question 37

veins have the Same 3 layers

Answer 37

Tunica interna thinner than arteries Tunica interna thinner with little smooth muscle Tunica externa thickest layer

Question 38

Not designed to withstand high pressure Valves – folds on tunica interna forming cusps Aid in venous return by preventing backflow

Answer 38

Veins

Question 39

blood passes through second capillary bed Hepatic or hypophyseal

Answer 39

Portal vein

Question 40

Thinner walls than arterial counterparts Postcapillary venule – smallest venule Form part of microcirculatory exchange unit with capillaries Muscular venules have thicker walls with 1 or 2 layers of smooth muscle

Answer 40

Venules

Question 41

typically consist of two elastic flaps of tissue that open and close in alternation. Venous valves work in conjunction with the musculoskeletal system. Muscles constantly contract and release, causing the blood to flow toward the heart.

Answer 41

Venous Valves

Question 42

Thin Walled Large irregular lumen Have valves Dead space around Types: Large Medium Small

Answer 42

VEINS

Question 43

Veins without valves:

Answer 43

SVC & IVC Hepatic, Renal Uterine, Ovarian not Testicular Facial Pulmonary Umbilical Emissary Portal Veins <2mm

Question 44

Veins without Muscular tissue:

Answer 44

Dural venous sinuses Pial Veins Retinal Veins of erectile tissue of sex organs Veins of spongy bones

Question 45

Factors responsible for venous return:

Answer 45

Muscle contraction Negative intrathoracic pressure Pulsation of arteries Gravity Valves

Question 46

Communication between vessels

Answer 46

ANASTOMOSIS

Question 47

Palmar, plantar, Circle of Willis, Labial Intestinal arcade, etc.

Answer 47

Actual( end to end & convergent)

Question 48

Coronary, around joints etc.

Answer 48

Potential

Question 49

ARTERIOVENOUS ANASTOMOSIS:

Answer 49

1. Skin of nose 2. Lips 3. External Ear 4. Mucus membrane of GI & nose 5. Erectile tissue of sex organ 5. Thyroid 6. Tongue

Question 50

END ARTERIES:

Answer 50

1. Central artery of retina 2. Arteries of spleen, liver, kidneys, metaphyses of long bones 3. Central branches of cerebral cortex

Question 51

Largest portion of blood at rest is in ___ & ____ Blood reservoir

Answer 51

systemic veins and venules

Question 52

reduces volume of blood in reservoirs and allows greater blood volume to flow where needed

Answer 52

Venoconstriction