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Flashcards in structure and function of circulation Deck (25)
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1
Q

what structures are in all blood vessels?

A

lumen, tunica intima , and media (all but capillaries) , and tunica externa (all but capillaries)

2
Q

what is tunica intima?

A

layer of endothelial cells on basement membrane

3
Q

what does tunica media contain?

A

elastic tissue + muscle (composition vaires)

4
Q

what can tunica externa contain?

A

collagen (strength)
nerves (large vein and arteries)
vasa vorium (large artery+vein)
lymphatics (larger vessels)

5
Q

what is vasa vorium?

A

network of blood vessels in outer layer of large arteries and veins

6
Q

what is medial layer in aorta/elastic arteries like?

A

smooth muscle in medial layer is replaced by many layers of ELASTIC TISSUE (cope with ejection pressures——
windkessel effect)

7
Q

what is composition of media in muscular arteries?

A

thick layer of smooth muscle

8
Q

what is ateriosclerosis?

A

thickening/toughening of arterial walls
involves ca depositation
aging disease diabetes

9
Q

what is athersclerosis?

A

lipid + monocyte deposition in tunica media
high LDLs, low Apoe
cholesterol

10
Q

what are arterioles?

A

smaller than arteries within tissues.

have 3 or less layers of smooth muscle (control)

11
Q

what do ACE inhibitors do?

A

reduce BP (ramipril, perindopril)

12
Q

what does angiotensin II do?

A

cause vasoconstriction (raise BP)
responds to drops in BP
can effect hypothalamus

13
Q

how many amino acids does AngiotensinII have?

A

8

14
Q

what are capillaries?

A

endothelial cells on basement membrane.

15
Q

what are fenestrations?

A

pores in capillaries

if large fenestrations -is discontinuous

16
Q

compare venules to arterioles

small vein

A

venules are less muscular than arterioles- more prone to collapse.

17
Q

compare veins to arteries

A

veins are less muscular but can open up more (more distensible ) . and veins can store blood

18
Q

what is structure of large veins?

A

have bundles of smooth muscle, (more muscular than venules)

contain pocket valves

19
Q

what are pocket valves?

A

folds in tunica intima - stop blood flowing in wrong direction.

20
Q

what are varacous veins form by?

A

poor valves (build up of blood)

21
Q

what is lympahtic system?

A

diffuse system that delivers excess tissue fluid to CVS.

central venous system

22
Q

what is caused by impaired flow in lympahtics?

A

oedema

23
Q

give some properties of lymphatics

A

blind ended, freely permeable, flap valves

24
Q

how do lymphatic system and CVS link?

A

via lymphatic ducts

25
Q

what causes elephantiasis?

A

wuchereria bancrofti

issues in lymph