PNB 2275 Exam 2

studied byStudied by 0 people
0.0(0)
get a hint
hint

blood must circulate so that it can…

1 / 182

Tags and Description

Biology

183 Terms

1

blood must circulate so that it can…

deliver nutrients and remove waste, provide immune protection and clotting functions, maintain homeostasis

New cards
2

rank hydrostatic pressure in arteries, capillaries, and veins

arteries (80-120 mmHg) > capillaries (15-35 mmHg) > veins (0-20 mmHg)

New cards
3

coronary arteries

deliver oxygenated blood to heart cells

New cards
4

coronary veins

drain into coronary sinus, which opens into right atrium; return deoxygenated blood from the heart cells back to the general circulation

New cards
5

functional classification of vessels

distribution, exchange, collection

New cards
6

characteristics of arteries

hold ~13% blood volume, need to withstand high pressure during ventricular systole

New cards
7

types of arteries

elastic, muscular, arteriole

New cards
8

elastic artery

large diameter, buffer changes in blood pressure because of pressure-storing ability due to lots of elastic tissue, conducting

New cards
9

muscular artery

medium diameter, most common type, distribution

New cards
10

arteriole

small diameter, no tunica externa (smooth muscle tunica media is on the outside instead), can alter peripheral resistance and effect blood pressure

New cards
11

how is diameter controlled in arterioles?

because there is no tunica externa, diameter can be controlled by local, autonomic, and hormonal factors

New cards
12

capillary characteristics

holds ~9% of blood volume, permit bi-directional flow, have thin walls made up of a single layer of endothelium cells and a connective basement membrane essential for exchange

New cards
13

capillary bed

large surface area, thin-walled vessels, mesh like network, contains thoroughfare channels and metarterioles

New cards
14

thoroughfare channels

within the capillary bed, direct flow between arteries and veins

New cards
15

metarterioles

small vessels with precapillary schincters (individal smooth-muscle cells in place of tunica media to regulate flow within and between beds)

New cards
16

Arteriovenous anastomosis

proximal to the capillary bed, allow alternate route of bloodflow in event of blockage

New cards
17

types of capillaries

continuous, fenestrated (window), sinusoid (large holes)

New cards
18

continuous capillaries

exchange small molecules without loss of RBCs or plasma protein, found in most tissue, thin continuous walls

New cards
19

fenestrated (window) capillaries

exchange small peptides; fenestrations = windows; found in hypothalamus, pituitary, intestine, kidneys

New cards
20

sinusoid (large holes) capillaries

exchange blood proteins and blood cells; like fenestrated but with larger windows and 5 times larger diameter; found in liver, marrow, spleen

New cards
21

characteristics of veins

accommodate low pressure on return to heart, hold ~64% of blood volume, thin walls allow veins to expand without rupture

New cards
22

how to veins deal with low pressure

skeletal muscle pump and respiratory pump

New cards
23

skeletal muscle pump for veins

Veins pass through skeletal muscles → when skeletal muscles contract, they push on the veins and move the blood; valves in the veins keep this flow unidirectional and prevent backflow during diastole

New cards
24

respiratory pump for veins

The drop in pressure in the chest cavity during inhalation reduces pressure on the veins; allows blood to flow back towards the heart

New cards
25

types of veins

venule, medium-diameter vein, large vein

New cards
26

venule

small diameter, no muscle (no real tunica media)

New cards
27

medium-diameter vein

medium diameter, some have valves (made of in-folding of the tunica intima), expand easily to accommodate volume changes (high compliance)

New cards
28

large veins

large diameter, can hold large blood volume, has three layers, but the layers are relatively thin

New cards
29

vein functions

low-resistance conduit of blood back to right atrium, venous blood reserve (central reflexes can decrease compliance to increase arterial blood volume)

New cards
30

the layers of arteries are ___ than the layers of veins

thicker

New cards
31

3 layers of arteries and veins

tunica externa, tunica media, tunica intima

New cards
32

tunica externa

outer layer, support, connective tissue made of collagen and elastic fibers, some smooth muscle

New cards
33

tunica media

middle layer, contraction, primarily smooth muscle surrounded and contained by internal/external elastic membranes, transverse elastic fibers

New cards
34

tunica intima

inner layer, lining, endothelial cells, longitudinal elastic fibers running the length of the vessel, subendothelial connective tissue

New cards
35

blood pressure =

cardiac output * total peripheral resistance

New cards
36

total peripheral resistance is also called

systemic vascular resistance

New cards
37

flow =

change in pressure/resistance = (P arterial - P venous)/resistance

New cards
38

flow occurs when system circulatory pressure is ___ total peripheral resistance

greater than

New cards
39

resistance

  • friction between blood and vessel wall

  • L = length

  • n = viscosity

  • r = radius

New cards
40

arrangement of vessels affects resistance…parallel arrangement has ___ resistance than series arrangement

lower

New cards
41

example of parallel arrangement of vessels

capillaries

New cards
42

flow =

velocity * area

New cards
43

with a constant flow, velocity and area are ___ proportional

inversely

New cards
44

how does surface area play a role in capillaries?

  • Capillaries have very narrow diameters, so we would think the velocity is high → this would give them no time to exchange which is bad since that’s their main job

  • BUT when you combine many capillaries, there is an aggregate cross-sectional area that is VERY HIGH

    • High area results in very slow blood velocity → this gives enough time for gas/nutrient exchange

New cards
45

Poiseuille’s Law

  • predicts blood flow rate in a vessel

  • delta P: pressure gradient

  • r: radius

  • n = viscosity

  • L = length of vessel

New cards
46

methods of capillary exchange

diffusion, transcytosis, bulk exchange

New cards
47

what happens at the arterial end of the capillaries

forces water OUT of the capillaries, hydrostatic pressure is the driving force

New cards
48

net hydrostatic pressure (NHP) =

capillary hydrostatic pressure (CHP) - interstitial hydrostatic pressure (IHP)

New cards
49

what values of NHP show flow in/out of capillaries

  • NHP > 0 → fluid flows out of capillaries

  • NHP < 0 → fluid flows into capillaries

New cards
50

what happens at the venous end of the capillaries

reabsorption, draws water INTO the capillaries, oncotic pressure is the driving force

New cards
51

oncotic

colloid osmotic pressure (COP) = osmotic pressure for large solutes

New cards
52

oncotic pressure =

molarity * RT (high concentration = high oncotic pressure)

New cards
53

net colloid osmotic pressure (NCOP) =

blood COP - interstitial COP

New cards
54

equation for net filtration pressure =

NHP (net hydrostatic pressure) - NCOP (net colloid osmotic pressure)

New cards
55

positive net filtration pressure indicates

net flow out

New cards
56

negative net filtration pressure indicates

net flow in

New cards
57

exchange equation that incorporates filtration coefficient and reflection coefficient

NFR = Kf (Pc - Pi) - σ (πc - πi)

New cards
58

reflection coefficient (σ)

  • an adjustment for oncotic pressure

  • high σ = low protein permeability (ex. glomerulus, brain)

  • low σ = high protein permeability (ex. liver, spleen)

New cards
59

filtration coefficient (Kf)

  • high Kf = high H2O permeability (ex. kidneys)

  • low Kf = low H2O permeability

New cards
60

major functions of lymphatic system

  • homeostatic re-circulation: collects excess leaked fluid from the capillaries and returns it to the blood circulation

  • absorption: transport absorbed fat to blood via lacteals

  • immune: Production, maintenance, and distribution of lymphocytes (T-cells and B-cells); delivery of pathogens, antigens, and dendritic cells to lymph nodes

New cards
61

lacteals

specialized structures in intestinal villi that transport absorbed fat

New cards
62

how does lymphatic flow occur? what is the speed?

  • slow

  • occurs by skeletal muscle pump and peristaltic smooth muscle contraction

  • helped by valves

New cards
63

what happens when the lymphatic system doesn’t recover excess fluid?

edema

New cards
64

what could cause edema?

increased capillary pressure, decreased plasma proteins, increased capillary permeability, blockage of lymph return

New cards
65

Viagra → ___ PDE3 → does not allow conversion of cGMP and cAMP to GMP and AMP → more cGMP and cAMP → smooth muscle ___ → blood vessels ___ → more blood flow → PENILE ERECTION!!!

inhibits, relaxes, dilate

New cards
66

does smooth muscle have sarcomeres?

no

New cards
67

does smooth muscle have troponin?

no

New cards
68

Opening of IP3 receptors (and some RyR) on sarcoplasmic reticulum release ___ into the cytoplasm

Ca2+

New cards
69

what regulates contraction in smooth muscles

myosin light chain (MLC)

New cards
70

MLC is regulated by ___, which leads to ___

calmodulin/MLC kinase (MLCK), contraction

New cards
71

MLC phosphatase reverses ___ function, leading to ___

MLCK, relaxation

New cards
72

Smooth muscle activity constricts and dilates ___

blood vessels

New cards
73

epinephrine functions

increases cardiac output, heart rate, stroke volume, and contractile force

New cards
74

pathway for increased contractile force

epi → beta-1 adrenergic receptor → Gsa → cAMP → PKA

New cards
75

what receptor does epi bind to increase blood pressure?

alpha-1 adrenergic on smooth muscle of blood vessels

New cards
76

pathway for increasing blood pressure

thromboxane → Gq g-protein signaling → IP3 receptors on sarcoplasmic reticulum are activated → calcium is released into cytoplasm → increased contraction of smooth muscle → elevates BP

New cards
77

what does thyroid hormone do?

increases cardiac output, heart rate, stroke volume, and contractile force

New cards
78

how does TH increase contractile force

TH-receptor-mediated regulation of genes related to contractility; elevates Ca2+ ATPase pump and decreases phospholamban

New cards
79

how does TH effect blood pressure?

decreases it

New cards
80

what receptor does TH bind to to effect blood pressure

beta-2 adrenergic receptor

New cards
81

pathway of TH effect on blood pressure

TH increases expression of beta-2 adrenergic receptors → activates cAMP → inhibits MLCK → relaxes smooth muscle → dilation of blood vessels → decreased BP → elevated blood flow to skeletal muscles

New cards
82

hyperthyroidism

low systemic vascular resistance (dilation of BP), high heart rate, increased ejection fraction, increased cardiac output

New cards
83

nitric oxide

gasouse signaling molecule

New cards
84

where and in response to what is NO released

released by endothelial cells in response to shear force of blood flow (high BP)

New cards
85

NO activates guanylate cyclase (GC) → ___ → ___

increases cGMP; activates protein kinase G (PKG)

New cards
86

what does NO release do to blood pressure

decrease it

New cards
87

how does NO make blood pressure go down?

  • Increases MLC phosphatase → inactivates MLC → muscle relaxation → dilates blood vessels → blood pressure goes down

  • Inhibits IP3-R receptors on sarcoplasmic reticulum, so Ca+ is not released and can’t bind to calmodulin → MLCK does not get activates → inactivates MLC  → muscle relaxation → dilates blood vessels → blood pressure goes down

New cards
88

compliance

  • how easily a heart chamber of blood vessel expands when filled with blood

  • change in volume over change in pressure

New cards
89

what is compliance on a curve of volume v.s. pressure

slope of the curve

New cards
90

veins have ___ compliance because they need to ___

high, have a large change in volume in response to a small change in pressure

New cards
91

veins have ___ elasticity

low (store very little pressure even with large volume changes)

New cards
92

arteries have ___ compliance because ___

low, a massive change in pressure is required for a small change in volume

New cards
93

arteries have ___ elasticity

high (a small volume change results in a large pressure change)

New cards
94

what are the 3 lines of defense in the immune system?

prevention of infection → targeted destruction of pathogens → specific targeting of pathogens/immunological memory

New cards
95

the first two line of defense of the immune system are ___

nonspecific

New cards
96

the third line of defense of the immune system is ___

specific

New cards
97

1st line: prevention of infection

  • Skin

  • Mucous membranes

  • Secretions of skin and mucous membranes

New cards
98

2nd line: targeted destruction of pathogens

  • Phagocytic white blood cells

  • Antimicrobial proteins

  • The inflammatory response

New cards
99

3rd line: specific targeting of pathogens; immunological memory

  • Lymphocytes

  • Antibodies

New cards
100

nonspecific lines of defense

  • first line: physical barriers, inflammatory response

  • second line: phagocytes, immunological surveillance, interferon, complement, fever

New cards

Explore top notes

note Note
studied byStudied by 20 people
Updated ... ago
4.0 Stars(1)
note Note
studied byStudied by 144 people
Updated ... ago
5.0 Stars(2)
note Note
studied byStudied by 4 people
Updated ... ago
5.0 Stars(1)
note Note
studied byStudied by 11009 people
Updated ... ago
4.9 Stars(52)
note Note
studied byStudied by 63 people
Updated ... ago
4.0 Stars(1)
note Note
studied byStudied by 8 people
Updated ... ago
5.0 Stars(1)
note Note
studied byStudied by 2 people
Updated ... ago
5.0 Stars(1)
note Note
studied byStudied by 77 people
Updated ... ago
5.0 Stars(1)

Explore top flashcards

flashcards Flashcard39 terms
studied byStudied by 2 people
Updated ... ago
5.0 Stars(1)
flashcards Flashcard31 terms
studied byStudied by 11 people
Updated ... ago
5.0 Stars(1)
flashcards Flashcard40 terms
studied byStudied by 133 people
Updated ... ago
5.0 Stars(1)
flashcards Flashcard52 terms
studied byStudied by 15 people
Updated ... ago
5.0 Stars(1)
flashcards Flashcard37 terms
studied byStudied by 14 people
Updated ... ago
5.0 Stars(7)
flashcards Flashcard49 terms
studied byStudied by 5 people
Updated ... ago
5.0 Stars(1)
flashcards Flashcard31 terms
studied byStudied by 2 people
Updated ... ago
5.0 Stars(1)
flashcards Flashcard306 terms
studied byStudied by 5 people
Updated ... ago
5.0 Stars(1)