Quiz2

Question 1

(general) what is in the tunica media (types)

Answer 1

smooth muscle cells, elastic, reticular and collagenous fibers type III and IV
-external elastic lamina surrounds it

Question 2

(general) what is in the tunica intima

Answer 2

subendothelial layer( thin CT), endothelium, and internal elastic lamina around that.

Question 3

Which BVs:

1. pressure highest, lowest
2. muscle highest, lowest
3. vasa vasorum highest, lowest
4. elasticity highest lowest (none)
5. speed of blood

Answer 3

1. arteries, veins (huge drop in capillaries)
2. arterioles, capillaries (none)
   - – less in venules and veins than arteries,arterioles
3. arteries and veins, none in arterioles, capillaries and venules
4. highest in large arteries aka elastic arteries/conducting down from there and none in capillaries, back up venules and higher in veins- but not distinct laminae
5. highest in arteries, slowest in capillaries.

Question 4

which bvs does external elastic lamina start to diminish

Answer 4

starts in muscular (distributing) arties. less in small muscular arteries and none in arterioles

Question 5

which BVS does inner elastic lamina dissapear

Answer 5

arterioles

• still exists in the “transition” from muscular artery to arteriole
• none in arterioles, capillaries, then back again in venules and veins.

-slide 8

Question 6

how many layers of muscle are in arterioles

Answer 6

2-3 layers. terminal arterioles are 1 muscle cell thick.

Question 7

what is the junction of capillaries and arterioles

Answer 7

precapillary sphincter

Question 8

which bvs have most control over BP

Answer 8

arterioles (resistance)

Question 9

how to tell venule from arteriole

Answer 9

venules have larger lumens and less distinct muscular layers

Question 10

(general) what is in the tunica adventita`

Answer 10

loost connective tissue, blood vessels (vasa vasorum) , lymphatics and nerves (nervi vassorum)

Question 11

what are the 3 types of capillaries, where are they and defining features

Answer 11

1. continuous capillaries (muscles and CNS) : occluding junctions make the endothelium tight together. basement membrane wraps completely. gas exchange and pinocytosis, and transcytosis
2. fenestrated capillaries (endocrine glands, kidneys, small intestine) - fenestrations /openings in the endothelium can have diaphrams sometimes.basement membrane is continous throughout but more readily allow filtration nutrients etc across capillary wall.
3. discontinuous capillaries (liver, spleen, bone marrow) fenestrations are larger than in fenestrated, and basement membrane is DISCONTINUOUS!! red blood cells can leave in the spleen ONLY!

Question 12

what are the functions of endothelial cells

Answer 12

• permeability barrier
• modulates vascular tone
• promotes angiogenesis( dev of new BVs)
• trigggers blood coagulation
• inibits platelet adhesion
• regulates inflammatory cell migration

Question 13

what are anastomes

Answer 13

connection between blood vessels, could be arterioles and venules or even two arterioles or two venules. just means a direct conneciton between bvs

Question 14

what is collateral circulation

Answer 14

when there are alternative blood supply pathways!! like multiple arterioles going into a capillary bed, if ones cut off, the cap bad still provides blood all over the area.

Question 15

what are end arteries

Answer 15

when theres only ONE pathway to something like retina central artery, if its cut off, retina dies (unlike collateral)

Question 16

what are arteriovenous shunts

Answer 16

or AV shunt

• where theres a connection from an arteriole to a venule without going through a capillary bed, bypass of cap bed so we dont lose as much body heat through the skin, thats an inmportant function of it.
• also if jogging, dont need a lot of blood in walls of digestive tract, etc. shunt blood away

Question 17

what is a portal system (examples)

Answer 17

takes blood from one capillary bed directly to another capillary bed with no heart circulation in between.

• portal vein from gut to liver
• also in kidneys, pituitary gland etc

Question 18

what is the pathway of venous return?

Answer 18

capillary -> postcapillary venules -> collecting venules -> muscular venules -> small veins -> large veins

– gradually gets larger

Question 19

differences between arteries and veins

Answer 19

veins: larger lumen, t adventita is thickest layer, thinner wall overall . have valves. more numerous and variable than arteries. muscular tunica media is thinner than in arteries, smooth muscle fibers have irregular orientation, circular approximately.
arteries: thicker wall, thinner lumen. no valves.

Question 20

what are vein valves made up of

Answer 20

=projections into lumen of tunica intima. covered by endothelial cells, have a core of elastic fibers.

Question 21

what is arteriosclerosis

Answer 21

hardening and narrowing of arteries (loss of elasticity and thickening)
-within the tunica intima layer, between that and tunica media. its infiltration of cholesterol and other lipid substances into vessel wall, harden over time and become hard plaques.

(sclerosis means hardening)

-aneurysm is a weakness in blood vessel wall that allows ballooning out , may burst.

Question 22

what are embolus and thrombus

Answer 22

embolus is the large plaque that builds up in a arteri in arteriosclerosis. thrombus is it when it breaks free and enters circ system.

Question 23

what vessels have valves

Answer 23

veins and lymphatic vessels

large venuoles?

Question 24

how do lymph vessels drain

Answer 24

they are “blind ended” , blind lymphatic capillary endings, not actually connected to capillaries. (blunt openings)

Question 25

how do things move in lymphatic system

Answer 25

due to Surrounding muscle. no pericytes or muscle of its own. -takes 10%, other 90% goes to venous end.

Question 26

what are lymph vessels made up of, where does it pick up blood and how is it anchored

Answer 26

endothelium with little or no basement membrane, no pericytes, have valves,. - picks up through blind sacs. - anchoring filaments attach endothelial cells of lymph capillaries to connective tissue surrounding it, prevents lumen from collapse.

Question 27

how to tell lymph vessel from blood vessels on a histology slide

Answer 27

thin layer vs venule, but no red blood cells.

Question 28

whats a neurovascular bundle

Answer 28

artery, vein and nerve bundled together. | -can tell nerve bc it has nuclei of nerve fibers in lumen.

Question 29

what are the layers of the epidermis

Answer 29

top to bottom: - stratum corneum (cornified layer) - stratum lucidum (lucid layer) - stratum granulosum (keratohyaline granules, filaggrin, lamellar bodies) - stratum spinosum (desmosomes, tonofilaments- cytokeratins), basal layer (hemidesmosome, anchoring filaments, basal lamina (lucida and densa)

Question 30

which cells of epidermis derive from neural crest (that we know)

Answer 30

melanocytes and merkel cells.

Question 31

where do you find meissner corpuscle cells

Answer 31

(tactile) | - in dermal papillae attached to epidermis with collagen fibers.

Question 32

where do you find merkel cells

Answer 32

they extend up and the merkel disc/nerve ending is inserted into the bottom of the epidermis

Question 33

what are the components to the attachment of keratinocyte basal cells to the basal lamina

Answer 33

basal cells attach to the lamina lucida by hemidesmosomes. tonofibrils (cytokeratins) extending from the cytoplasm of the basal cell insert into the hemidesmosomes. - under hemidesmisome is a plate and then a plaque inserted into the plasma membrane. Integrins and bullous pemphigoid antigens insert into the plaque and extend into the lamina lucida. - also attached to anchoring filaments, laminin 5 of the lamina lucida layer of the basement membranes basal lamina

Question 34

what do pacinian corpuscles look like , where are they and what do they detect

Answer 34

they look like ONIONS! | -found deep in hypodermis. They sense pressure!

Question 35

what is in the granular layer

Answer 35

stratum granulosum -has keratohyaline granules , filaggrins which bind to keratin, and lamellar bodies (lipid based) which become the compound cellular envelope on the outside of the cell in the stratum LUCIDUM AND CORNEUM. also in stratums lucidum and corneums, proteins form cornified cell envelope on inside of plasma membrane .

Question 36

what is the nerve that senses stretching, where is it ?

Answer 36

in the dermis, its called ruffini end organ

Question 37

which cells of epidermis derive from neural crest (that we know)

Answer 37

melanocytes and merkel cells.

Question 38

where do you find meissner corpuscle cells

Answer 38

(tactile) | - in dermal papillae attached to epidermis with collagen fibers.

Question 39

where do you find merkel cells

Answer 39

they extend up and the merkel disc/nerve ending is inserted into the bottom of the epidermis

Question 40

what do nerve endings detect in skin and where are they

Answer 40

they extend from dermis into the epidermis. they detect pain and temperature

Question 41

what do pacinian corpuscles look like , where are they and what do they detect

Answer 41

they look like ONIONS! | -found deep in hypodermis. They sense pressure!