Lab 6: circulatory system

Question 1

name layers from lumen outwards

Answer 1

intima
media
adventitia

Question 2

describe intima

Answer 2

endothelium - simple squamous with BM
subendothelium - loose CT between endothelium and IELM
internal elastic membrane (IELM) - not in all vessels, like elastic fibers in tunica media but thicker

Question 3

describe media

Answer 3

smooth muscle
collagen type 3 - reticular fibers
elastic fibers

Question 4

describe elastic fibers of media

Answer 4

visible layers that separate smooth muscles into clear layers
fenestrated elastic membrane
not present in all vessel types

Question 5

describe adventitia

Answer 5

collagen type 1 (normal CT)
vasa vasorum - supply blood to large blood vessels, vessels of vessels
vasa nervosum

Question 6

describe plane of section for endothelium

Answer 6

run length of blood vessel

Question 7

describe plane of section for smooth muscle

Answer 7

when present = run circularly around blood vessel

Question 8

describe plane of section in cross section

Answer 8

endothelium in cross section
smooth muscle in longitudinal section

Question 9

describe plane of section in longitudinal section

Answer 9

endothelium in longitudinal section
smooth muscle in cross section

Question 10

describe capillaries - gen

Answer 10

only see endothelium (simple squamous with BM) and nucleus
smallest vessel
8-10um in diameter - enough to let one rbc 7um through
abundant in brain and heart

Question 11

what do capillaries not have

Answer 11

no media or adventitia

Question 12

describe lumen of capillaries

Answer 12

lined with 1-2 endothelial cells
allows only 1 rbc to fit through

Question 13

name the 3 types of capillaries

Answer 13

continuous
fenestrated
fenestrated sinusoids

Question 14

what do the 3 types of capillaries define

Answer 14

3 layers of permeabilization

Question 15

describe intima of arteriole

Answer 15

endothelium
Subendothelium thin
IELM likely absent

Question 16

describe media of arteriole

Answer 16

1-3 layers
appears longitudinal in cross section

Question 17

describe adventitia of arteriole

Answer 17

very little/no adventitia

Question 18

describe intima of venule

Answer 18

endothelium present
subendothelium thin
no IELM

Question 19

describe media of venule

Answer 19

no smooth muscle layers
incomplete or absent media

Question 20

describe adventitia of venule

Answer 20

very little/no adventitia

Question 21

how to distinguish venule from arterioles and capillaries

Answer 21

different from ateriole since no media
different from capillaries since more than one rbc can flow at a time
more than 2 endothelial cells surround lumen in cross section

Question 22

describe intima of muscular artery

Answer 22

endothelium (endothelial cell)
IELM very clear

Question 23

describe media of muscular artery

Answer 23

4-10 layers of smooth muscle

Question 24

describe adventitia of muscular artery

Answer 24

dense irregular CT
thin - in larger vessels can have vasa vasorum

Question 25

describe how smooth muscle cells look in cross section and longitudinal section of muscular artery

Answer 25

cross section = nuclei of smooth muscle appears longitudinal longitudinal section = smooth muscle appears in cross section

Question 26

describe intima of elastic artery

Answer 26

endothelial cell IELM present but difficult to differentiate between elastic fibers in media

Question 27

describe media of elastic artery

Answer 27

smooth muscle appears longitudinal (when in cross section) 10-50 layers of smooth muscle with distinct elastic fibers

Question 28

describe adventitia of elastic artery

Answer 28

vasa vasorum for nutrients and oxygen

Question 29

can elastic arteries be easily seen in light microscopy

Answer 29

NO so large that they may not be seen in light microscopy field all at once

Question 30

describe intima of large vein

Answer 30

no IELM (absent or undefined) endothelial cells

Question 31

describe media of large vein

Answer 31

can contain some smooth muscle but much less than artery of equivalent size

Question 32

describe adventitia of large vein

Answer 32

looks thicker than size of media has vaso vasorum