Circulatory System

Question 1

Are arteries or veins more fibrous? Which one carries high pressure blood

Answer 1

Veins are more fibrous. arteries carry high pressure blood

Question 2

What is the outer layer of arteries or veins

Answer 2

Tunica adventitia/externa

Question 3

What makes up tunica adventitia

Answer 3

connective tissue of collagen fibers, smooth muscle in veins, vasa vasorum and nerves

Question 4

What is the vasa vasorum

Answer 4

nourishing blood vessels, venules and arterioles

Question 5

What is the orientation of fibers of the tunica adventitia

Answer 5

longitudinal

Question 6

what is the middle layer of vessels

Answer 6

tunica media

Question 7

what makes up the tunica media

Answer 7

smooth muscle cells and elastictissue (especially in large elastic arteris like the aorta)

Question 8

what orientation is the tunica media

Answer 8

circumfrential

Question 9

what is the inner layer of vessel

Answer 9

tunica intima

Question 10

What lines the tunica intmia

Answer 10

endothelial cells (and internal elastic membrane for muscular arteries)

Question 11

Does every vessel have a a thick internal elastic membrnae? where is it?

Answer 11

nope just muscular arteries between the tunica intima and media

Question 12

Between companion arteries and veins which have a thicker wall?
a wider lumen?

Answer 12

veins have a thinner wall and a wider lumen

Question 13

When comparing veins and artieries which one has a more promiment t.a and which t.m

Answer 13

veins - tunica adventitia and arteries t.m.

Question 14

Where would an external elastic membrane be found

Answer 14

between t.a. and t.m. in muscular arteries.

Question 15

What is the equivalent layers in the hear

Answer 15

endocardium, myocardium, epicardium

Question 16

what is in the myocardium

Answer 16

thick layer of cardiac muscle cells (as opposed to smooth muscle cells)

Question 17

The valves of the heart are made of which layer?

Answer 17

elaboration of the endocardium

Question 18

How big is a large artery? medium? small? arteriole?

Answer 18

large: greater than 1 cm
medium: 2-10mm
small: 0.1-2mm
arteriole: 10-100um

Question 19

Where is the vasa vasorum

Answer 19

tunica adventitia

Question 20

where do the degenerative processes of arteries happen(which layers)

Answer 20

t. intima and t. media

Question 21

In medium arteries do you see elastic tissue in the TM

Answer 21

no

Question 22

WHat part of arterioles places a role in blood pressure

Answer 22

muscular layer, contraction raises resistance to blood flow and relaxation can increase blood flow (like to the gi system after a meal)

Question 23

How many layers thick is the tunica media or small arteries and arterioles? do they both have collagen fibers

Answer 23

small arteries is 8-10 cell layer and arterioles are 1-2 cell layers
only small arteries shows collagen gibers not arterioles

Question 24

DO small arteries or arterioles have an internal elastic membrnae

Answer 24

small arteries do but arterioles do not

Question 25

what is the TA of arterioles like

Answer 25

thin ill defined sheath of CT

Question 26

What is arteriosclerosis? what layers

Answer 26

rigidity and fibrosis of the vascular walls in elastic and muscular arteries. it is an accumulation of collagen and elastic fibers in the TI and loss of smooth muscle and elastic fibers in the TM (instead you see collagen fibers and mineral salts)

Question 27

What happens to the TI in slides with arteriosclerosis

Answer 27

you see displaces lines of elastin and cracks radiating from the lumen

Question 28

what is atherosclerosis? what layer?

Answer 28

deposition of plaques in the TI of large and medium arteries. it affects major blood vessels -slow progressive accumulaiton of lipids and then accelerated accumulation of smooth muscle cells and collagen then you can get thrombosis and hematoma

Question 29

With atherosclerosis do you only see an accumulation of lipid?

Answer 29

first you see lipid accumulation then you see an accumulation of smooth cells and collagen as it gets worse

Question 30

In someone with atherosclerosis what does the TI look like

Answer 30

it is greatly thickened

Question 31

What is an aneurysm

Answer 31

ballooning of an artery due to the breakdown of the arterial wall

Question 32

What size are most named veins

Answer 32

medium veins

Question 33

How big are medium veins, small veins and venules?

Answer 33

large: greater than 1 cm medium: 1-10 nm small 0.1-1mm venule 10-100 um

Question 34

What is the most pronounced layer in a large vein?

Answer 34

TA extensive vasa vasorum, large smooth muscle bundle, clusters of collagen fibers

Question 35

Do capillaries have all the layers seen in other vessels

Answer 35

No, it is a single layer of endothelail cells and their basal lamina

Question 36

where do the vasodialating/constricting agents like Nitrous Oxide have effects to control blood flow

Answer 36

muscular arteries

Question 37

What are metaarterioles

Answer 37

final arterial step before capillaries , they have smooth muscle cells that act as pre capillary sphincters

Question 38

What type of cell lines capillaries? junctions between them

Answer 38

simple squamous endothelial with tight junctions

Question 39

Where are pericytes

Answer 39

surround the capillary wall but techinically not a part of the wall

Question 40

What is the function of pericytes

Answer 40

'stem cells' for the vascular system and can make endothelial , smooth muscle cells and more pericytes

Question 41

What are the three types of capillaries

Answer 41

continous, fenestrated, sinusoidal

Question 42

Which is three capillary types have the widest lumen

Answer 42

sinusoidal

Question 43

Where do you find continuous capillaries

Answer 43

muscle, skin, nervous and connective tissue | where movement is highly regulated

Question 44

What;s the identifying feature in continuous capillaries

Answer 44

pinocytotic vessicles (microvesicles)

Question 45

Whats a pinocyte

Answer 45

a microvesicle found in continuous capillary and fenestrated that transports things across the endothelial wall

Question 46

Where do you find fenestrated capillaries

Answer 46

GI, kidney, endocrine glands

Question 47

In fenestrated capillaries are the pores covered?

Answer 47

they may be covered by thin membranes or diaphragms which are thinner than a plasmalemma.

Question 48

Are there microvesicles in fenestrated capillaries

Answer 48

yes

Question 49

where do you find sinusoidal capillaries

Answer 49

liver, bone marrow, and lymph organs

Question 50

Is the basal lamina continuous in all three kinds of capillaries

Answer 50

no it is not in sinusoidal.

Question 51

What is the space of disse

Answer 51

perisinusoidal space in liver between hepatocytes and capillaries that is filled with plasma into which microvilli extend to absorb molecules.

Question 52

What are the two routes of movement across capillaries

Answer 52

large or small pore system

Question 53

how big is the small pore system?

Answer 53

9-11 nm think they are discontinuities between endothelial cell jxns

Question 54

WHat is the diameter of large pores

Answer 54

50-70 nm.

Question 55

What are examples of large pore movement

Answer 55

fenestrae and microvesicles

Question 56

What lumen do microvesicle open at

Answer 56

lumen or exterior side (abluminal) of the endothelial cells.