Histology: Heart and Vessels

Question 1

arteries

Answer 1

blood away from heart

Question 2

veins

Answer 2

blood toward heart

Question 3

exchange at capillaries?

Answer 3

nutrient, oxygen, waste

Question 4

capillary structure?

Answer 4

singe layer of simple squamous epithelium surrounded by basement membrane

Question 5

endothelium

Answer 5

the simple squamous epithelium lining vessels

Question 6

vessels?

Answer 6

all lined by epithelium

Question 7

red blood cell diameters?

Answer 7

7.5 microns

vessel is 8 microns (barely fits!)

Question 8

passive exchange

Answer 8

simple diffusion to capillaries

-small molecules (water-soluble) and water

Question 9

pinocytotic exchange

Answer 9

transport soluble high molecular weight molecules across endothelial wall

invaginations of cell membrane on both inner and outer surfaces

Question 10

diapedesis

Answer 10

ameboid migration movement that allows cells (WBCs and macrophages) to pass endothelium

also done by immune cells

Question 11

capillary junctions

Answer 11

adjacent cell membranes joined by tight junctions

prevent fluid loss
-not a strong adhesion

white blood cells can break these tight junctions

Question 12

red blood cells

Answer 12

can bend (flexible)

Question 13

fenestrae

Answer 13

in some organ capillary endothelium

thin windows
-pores closed by diaphragm thinner than unit membrane

Question 14

discontinuous capillary

Answer 14

sinusoid

Question 15

pericytes

Answer 15

cells surrounding capillaries and small venules

supportive - angiogenesis and vessel repair

may have contractile properties
-possible cause for constriction of vessels

Question 16

sinusoid

Answer 16

not continuous membrane (or basement membrane)

where you need an excessive amount of exchange

liver, spleen, bone marrow

Question 17

disse space

Answer 17

in liver
-allows direct communication between vascular space and parenchyma of organ

things can move back and forth

Question 18

phagocytic cells

Answer 18

in some sinusoids

-

Question 19

kupffer cells

Answer 19

liver sinusoids

Question 20

macrophages

Answer 20

bone marrow, spleen sinusoids

Question 21

tunica intima

Answer 21

nearest lumen

Question 22

tunica media

Answer 22

external to intima

Question 23

tinuca adventita

Answer 23

outermost vessel coat

aka tunica externa

Question 24

morphology tunica intima

Answer 24

endothelium surrounds lumen
basement membrane underlies endothelium

subendothelial connective tissue

fibroblasts and CT fibers some of which run longitudinally

Question 25

inner elastic lamina

Answer 25

IEL fenestarted layer composed of accumulated elastic fibers outermost component of tunica intima

Question 26

morphology of tunica media

Answer 26

consists largely of smooth muscle also connective tissue fibers circumferentially arranged -numerous CT fibers formed by specialized smooth muscle cells

Question 27

external elastic lamina

Answer 27

EEL concentration of elastic fibers form outermost component of tunica media

Question 28

morphology of tunica adventitia

Answer 28

largely connective tissue of moderate density longitudinally arranged** formed by fibroblasts merges with loose connective tissue

Question 29

classifications of arteries

Answer 29

arterioles medium sized - muscular arteries large sized - elastic arteries **continuous transitions between artery type

Question 30

arteriole

Answer 30

has less than 5 layers of smooth muscle*** tunica intima - very thin tunica media - 1-5 layers of smooth muscle -control blood flow, regulate BP, no visible external elastic lamina tunica adventitia - usually thinner than media (not well developed)

Question 31

capillary

Answer 31

have no smooth muscle

Question 32

medium arteries

Answer 32

muscular artery tunica intima - small amount of subendothelial CT present, also a well-developed IEL tunica media - 5-40 layers of smooth muscle smaller arteries have lower elastic fiber content, larger arteries have increasing quantities of elastin ANS control of smooth muscle regulates blood flow tunica adventitia -usually thinner than media, some elastic fiber near media, mostly composed of collagen

Question 33

elastic lamina

Answer 33

produced by smooth muscles help to create an elastic vessel want it to be able to maintain size** -efficient delivery

Question 34

what is larger?

Answer 34

veins larger than artery because it is lower pressure

Question 35

large artery

Answer 35

elastic artery tunica intima - endothelial cells may be polygonal subendothelial CT relatively thick with many fibers IEL present but not as distinct muscular arteries tunica media - smooth muscle fibers, much elastic fiber accumulation elastic lamina - numerous thin tubular elastic membranes tunica adventitia - thinner than media, exclusively CT

Question 36

radial artery

Answer 36

medium artery

Question 37

verhoefs stain

Answer 37

silver staining | elastic fibers take it up

Question 38

vasa vasorum

Answer 38

small nutrient arteries supplying walls of larger arteries blood supply to the wall of larger vessels

Question 39

carotid body

Answer 39

mass of epitheliod and nerve endings found at biurcation of common carotid to internal and external stimulates response in response to lowered blood O2

Question 40

carotid sinus

Answer 40

dilation of internal carotid artery contains specialized nerve endings in response to blood pressure

Question 41

vein classification

Answer 41

venules -post-capillary and muscular small veins medium veins large veins

Question 42

pericytic venules

Answer 42

post-capillary venules

Question 43

vein structure

Answer 43

``` tunica intima -diffuse IEL, only larger veins tunica media -major point of difference -not prominent layer in veins (but it is in arteries) tunca adventitia -where you find venous smooth muscle -thickest part of vein ```

Question 44

valves

Answer 44

in medium veins -and in lower limb paired invagination of tunica intima free edges face in direction of blood flow have intimal core -reinforced by collagen and elastic fibers absent in portal systems assist under low blood pressure

Question 45

venule structure

Answer 45

tunica adventitia - thickest part | primarily

Question 46

medium vein structure

Answer 46

see notes**

Question 47

large vein structure

Answer 47

see notes** vena cava, portal vein

Question 48

arteries versus veins

Answer 48

see notes**

Question 49

cardiac muscle

Answer 49

see notes**