Ap 2 - Ch 21 - Blood Vessels

Front 1

Growth of new blood vessels.

Back 1

Angiogenesis

Front 2

Forces involved in circulating blood & blood vessels.

Back 2

Hemodynamics

Front 3

Blood vessel that carries blood away from heart to tissues.

Back 3

Artery

Front 4

Small artery that connect to capillaries.

Back 4

Arteriole

Front 5

Site of substance exchange b/w blood & tissues.

Back 5

Capillary

Front 6

Blood vessel that connect capillaries to larger veins.

Back 6

Venules

Front 7

Blood vessel that bring blood from tissue back to heart.

Back 7

Veins

Front 8

Small blood vessels that supply the walls of arteries/veins.

Back 8

Vaso vasorum

Front 9

What are the 3 layers that line BV from innermost to outermost?

Back 9

Tunica interna (intima), tunica media, tunica externa

Front 10

Innermost layer of tunica interna made of simple squamous epithelium that is continuous w/ endocardial heart lining. Influence blood flow, secrete chemical mediators, assist w/ capillary permeability.

Back 10

Endothelium

Front 11

Middle layer of tunica interna that provides support base for epithelial layer. Collagen fibers affords basal lamina tensile strength & resilience for stretching, recoil.

Back 11

Basement membrane

Front 12

Outermost layer of tunica interna. Thin sheet of elastic fibers w/ openings that allow diffusion from tunica interna to tunica media.

Back 12

Internal elastic lamina

Front 13

Which layer of the BV is most variable?

Back 13

Tunica media

Front 14

Middle layer of BV made of smooth mm & elastic fibers called ___ separating layer from tunica externa. Regulates BV diameter --> flow/pressure, contract when BV damaged to limit blood loss.

Back 14

Tunica media. External elastic lamina.

Front 15

Outer layer of BV that anchors vessel to surrounding tissues & contains nerves, vaso vasorum. Made of elastic, collagen fibers.

Back 15

Tunica externa

Front 16

In arteries, which layer is the thickest?

Back 16

Tunica media

Front 17

What are the 2 functional properties of arteries?

Back 17

Elasticity (elastic fibers allows high pressure blood flow), contractility (smooth mm allow vasodilation/constriction & can limit blood loss).

Front 18

How does increase vs. decrease in SNS firing affect vasodilation/vasoconstriction of arteries?

Back 18

Increase SNS - vasoconstriction. Decrease SNS - vasodilation.

Front 19

What are 7 elastic arteries in the body?

Back 19

Aorta, brachiocephalic, common carotid, subclavian, vertebral, pulmonary, common iliac.

Front 20

Large BV w/ more elastic fibers & less smooth mm. Well-defined internal/external elastic laminae, thick tunica media w/ more elastic fibers (elastic lamellae).

Back 20

Elastic arteries

Front 21

Elastic arteries are also called ___ b/c they conduct blood from heart to mid-sized mm arteries.

Back 21

Conducting arteries

Front 22

Elastic arteries function as ___ by storing mechanical energy so they can ___ during what phase of the heart?

Back 22

Pressure reservoir. Recoil. Diastole.

Front 23

BV w/ large amount of smooth mm in thick walls & distribute blood to various parts of body. Well-defined internal elastic lamina, thin external elastic lamina. Capable of vasoconstriction/dilation. Also called ___.

Back 23

Muscular arteries. Distributing arteries.

Front 24

Ability of smooth mm to contract & maintain partial contraction in BV is called ___. Important in maintaining pressure/blood flow.

Back 24

Vascular tone

Front 25

Union of branches of 2+ arteries supplying same region. Provide alternate routes for blood to reach tissue/organ.

Back 25

Anastomoses

Front 26

Alternate flow of blood to a body part through anastomoses.

Back 26

Collateral circulation

Front 27

Arteries that don't anastomose are known as ___. Obstruction of this can lead to death of the segment.

Back 27

End arteries

Front 28

Transitional vessel b/w arteriole & capillaries. Proximal end has some smooth mm, distal end none.

Back 28

Metarteriole

Front 29

Ring of smooth mm at metarteriole-capillary junction that regulate blood flow into capillaries & alter blood pressure.

Back 29

Precapillary sphincter

Front 30

Arterioles AKA ___ b/c they regulate resistance in BV through constriction/dilation.

Back 30

Resistance vessels

Front 31

Resistance is opposition of blood flow determined by amount of ___ b/w vessel walls & blood flowing through.

Back 31

Friction

Front 32

Flow of blood through capillaries is called ___.

Back 32

Microcirculation

Front 33

Capillary distribution varies w/ ___ of tissue.

Back 33

Metabolic activity

Front 34

Which structures have high metabolism = more capillaries? Which have less? Which don't have any capillaries?

Back 34

Mm, liver, kidneys, nervous system (a lot). Tendons, ligaments (less). Lens, cornea, interstitial fluid (none).

Front 35

Capillaries have endothelium, basement membrane, but no ___ to allow diffusion.

Back 35

No tunica media/externa.

Front 36

What effect does capillary branching have on the body?

Back 36

Increases surface area to allow rapid exchange of large quantities of material.

Front 37

Network of 10-100 capillaries that arise from single metarteriole.

Back 37

Capillary bed

Front 38

Intermittent contraction/relaxation of precapillary sphincters. At rest blood flows through 25% capillaries.

Back 38

Vasomotion

Front 39

When precapillary sphincters contract, blood is restricted to ___ of metarteriole. This provides a direct route from arteriole-venule, bypassing capillaries.

Back 39

Thoroughfare channel

Front 40

What are the 3 types of capillaries?

Back 40

Continuous, fenestrated, sinusoids

Front 41

Type of capillary that is continuous tube of endothelial cells w/ intercellular clefts for diffusion in tissues. Most common. Skeletal/smooth mm, connective tissue, lungs.

Back 41

Continuous capillary

Front 42

Type of capillary w/ pores in endothelial cells for easier diffusion. Kidneys, small intestine villi, endocrine glands, brain ventricles.

Back 42

Fenestrated capillary

Front 43

Type of capillary w/ large fenestrations. Basement membrane incomplete or absent & large intercellular clefts. Liver, spleen, red bone marrow, endocrine glands.

Back 43

Sinusoid

Front 44

Type of venule that receives blood from capillaries & function as exchange site of nutrients, wastes, WBC emigration.

Back 44

Postcapillary venule

Front 45

Type of larger venule w/ thicker walls so exchange w/ interstitial fluid no longer occurs.

Back 45

Muscular venule

Front 46

Which layer in the vein is thick vs. thin? How does elastic tissue/smooth mm differ from arteries?

Back 46

Thinner tunica interna/media. Thicker tunica externa. Less elastic tissue/smooth mm so thinner-walled than arteries.

Front 47

Veins contain ___ that prevent blood backflow, especially in lower limbs. Derived from tunica interna.

Back 47

Valves

Front 48

What 2 factors move venous blood back to heart?

Back 48

Heart pumping (major factor), skeletal mm contraction.

Front 49

Veins w/ very thin walls & no smooth mm to alter diameters. Ex, brain superior sagittal sinus, coronary sinus of heart.

Back 49

Vascular (venous) sinus

Front 50

What are 3 types of veins? Which is the major pathway for upper limbs vs. lower limbs?

Back 50

Anastomotic, superficial (subQ layer) - upper limb, deep (b/w skeletal mm) - lower limb.

Front 51

Weak valves in veins can lead to ___.

Back 51

Varicose veins

Front 52

What are common sites for varicose veins? Which vein is very susceptible?

Back 52

Esophagus, superficial veins of lower limbs, veins in anal canal. Saphenous vein most susceptible.

Front 53

At rest, largest portion of blood is in ___ & ___, collectively called ___.

Back 53

Systemic veins & venules. Blood reservoirs.

Front 54

What are the principle blood reservoirs?

Back 54

Veins of abdominal organs (liver, spleen) & skin.

Front 55

What are the 3 methods that substances enter/leave capillaries? Which is the most important method?

Back 55

Diffusion, transcytosis, bulk flow (filtration/reabsorption). Most important - simple diffusion.

Front 56

What are 3 ways substances may cross capillary walls?

Back 56

Intercellular clefts, fenestrations, through endothelial cells.

Front 57

What area is an exception of diffusion of water-soluble materials across capillary walls?

Back 57

Blood-brain barrier

Front 58

Process where substances are enclosed in vesicles that enter endothelial cells by endocytosis, move across, exit other side by exocytosis. What hormone travels this way?

Back 58

Transcytosis. Insulin.

Front 59

Passive process where large number of ions/molecules/particles in fluid move together in same direction.

Back 59

Bulk flow

Front 60

Diffusion is more important for ___ exchange b/w plasma & interstitial fluid. Bulk flow is more important for regulation of ___ of blood & interstitial fluid.

Back 60

Solute. Volume.

Front 61

Movement out of blood into interstitial fluid.

Back 61

Filtration

Front 62

Movement from interstitial fluid into blood.

Back 62

Reabsorption

Front 63

What 2 pressures promote filtration?

Back 63

Blood hydrostatic pressure, interstitial fluid osmotic pressure.

Front 64

Pressure that water portion of plasma exerts against blood vessel walls. 35mmHg. Does it push/pull fluid in/out of capillaries?

Back 64

Blood hydrostatic pressure. Pushes fluid out of capillary.

Front 65

Pressure resulting from protein particles in IF. Does it push/pull fluid in/out of capillaries?

Back 65

Interstitial fluid osmotic pressure. Pulls fluid out of capillary.

Front 66

Main pressure promoting reabsorption of fluid into blood. Caused by large plasma proteins that pull fluid from interstitial spaces into capillaries.

Back 66

Blood colloid osmotic pressure.

Front 67

Does interstitial fluid hydrostatic pressure push/pull fluid into/out of capillary?

Back 67

Pushes fluid into capillary.

Front 68

At the arterial end, there is a net inflow/outflow.

Back 68

Outflow

Front 69

At the venous end, there is a net inflow/outflow. What is the blood hydrostatic pressure?

Back 69

Inflow. 16mmHg.

Front 70

Approx 85% of filtered substance is reabsorbed & excess fluid is picked up by ___ & returned to circulation.

Back 70

Lymphatic system

Front 71

What is Starling's law of capillaries?

Back 71

Near equilibrium at arterial/venous ends of capillary by which fluids exit/enter.

Front 72

Abnormal increase in IF when balance of filtration/reabsorption is disrupted.

Back 72

Edema

Front 73

What 5 factors can cause edema?

Back 73

Increased BHP, decreased plasma proteins, increased permeability of capillaries, increased ECF, blockage lymphatic vessels.

Front 74

How is net filtration calculated?

Back 74

NFP = (BHP + IFOP) - (BCOP - IFHP)

Front 75

Distribution of cardiac output depends on what 2 factors?

Back 75

Pressure difference (that drives blood flow), resistance to blood flow.

Front 76

Highest arterial pressure during systole vs. lowest arterial pressure during diastole.

Back 76

Systolic BP vs. diastolic BP

Front 77

Average blood pressure in arteries & rougly 1/3 way b/w systolic/diastolic pressure.

Back 77

Mean arterial pressure

Front 78

What are 2 ways MAP can be calculated?

Back 78

MAP = diastolic BP + 1/3(systolic BP - diastolic BP) OR MAP = CO x R

Front 79

What are 5 factors that affect blood pressure?

Back 79

Cardiac output, blood volume, viscosity, resistance, artery elasticity

Front 80

Opposition of blood flow as result of friction b/w blood & walls of BVs.

Back 80

Resistance

Front 81

Vascular resistance depends on what 3 factors?

Back 81

Size of lumen, blood viscosity, total BV length.

Front 82

In what type of population is high BP often present?

Back 82

Obese people

Front 83

All vascular resistances offered by systemic BVs; most resistance is in arterioles, capillaries, venules due to diameters.

Back 83

Systemic vascular resistance (total peripheral resistance)

Front 84

Why does venous return occur?

Back 84

Pressure gradient b/w venules (16mmHg) & R atrium (0 mmHg)

Front 85

What 3 factors help blood return to the heart?

Back 85

Skeletal mm pump, vein valves, respiratory pump.

Front 86

Blood flow caused by compression of vein valves.

Back 86

Milking

Front 87

Time required for drop of blood to travel from R atrium & back. Normal 1 min.

Back 87

Circulation time

Front 88

Blood flows most slowly where cross-sectional area is (greatest/smallest).

Back 88

Greatest

Front 89

Blood flow (increases/decreases) from aorta to arteries to capillaries & (increases/decreases) as it returns to heart.

Back 89

Decreases. Increases.

Front 90

Fainting/loss of consciousness followed by spontaneous recovery. 4 types: vasodepressor, situational, drug-induced, orthostatic.

Back 90

Syncope

Front 91

What type of BV is the main regulator of systemic vascular resistance? How does it do this?

Back 91

Arterioles - vasoconstriction/dilation.

Front 92

Group of neurons in medulla that regulate HR, contractility, BV diameter.

Back 92

Cardiovascular center

Front 93

Sympathetic impulses from CV travel via ___ to increase HR, contracility.

Back 93

Cardiac accelerator nn

Front 94

Parasympathetic impulses from CV travel via ___ to decrease HR.

Back 94

Vagus nn

Front 95

___ nerves send impulses to smooth mm resulting in vasoconstriction called ___.

Back 95

Vasomotor nn. Vasomotor tone.

Front 96

Baroreceptors detect ___ & are found in what 2 arteries?

Back 96

Stretch. Aorta, internal carotid arteries.

Front 97

Reflex that maintains normal BP in brain.

Back 97

Carotid sinus reflex

Front 98

Reflex that maintains general systemic BP.

Back 98

Aortic reflex

Front 99

If BP drops, CV center will decrease (PNS/SNS) stimulation of heart via ___ nn & increase (PNS/SNS) stimulation via ___ nn.

Back 99

PNS. Vagus nn. SNS. Cardiac accelerator nn.

Front 100

SNS stimulation for BP drop causes release of what 2 hormones from adrenal medulla?

Back 100

Epinephrine/norepinephrine

Front 101

Receptors that detect chemicals located in carotid sinus & arch of aorta. What 3 substances do they detect?

Back 101

Chemoreceptors. Oxygen, carbon dioxide, hydrogen ions.

Front 102

Which cranial nn conducts impulses to CV from baroreceptors in carotid sinuses & arch of aorta?

Back 102

Glossopharyngeal nn.

Front 103

What 5 hormones affect blood pressure/flow? In what 3 ways?

Back 103

Angiotensin II, epinephrine, norepinephrine, antidiuretic hormone, atrial natriuretic peptide. By altering cardiac output, systemic vascular resistance, total blood volume.

Front 104

How does aldosterone affect BP?

Back 104

Causes kidneys to reabsorb more Na+ which causes water to follow. Results in increased blood volume & BP.

Front 105

Which hormones raise BP by increasing CO (HR & heart contraction force)? How does it affect BV during exercise in skin, abdominal organs, cardiac/skeletal mm? Released by adrenal medulla.

Back 105

Epi/norepi. Vasoconstriction skin/abdominal organs. Vasodilation - cardiac/skeletal mm.

Front 106

Which hormone raises BP by causing vasoconstriction to increase vascular resistance & stimulates aldosterone secretion?

Back 106

Angiotensin II.

Front 107

Which hormone AKA vasopressin is released by hypothalamus & causes vasoconstriction to raise BP? Release due to dehydration/decreased blood volume.

Back 107

Antidiuretic

Front 108

Which hormone is released by atria & lowers BP by vasodilation & promotes salt/water loss in urine to decrease blood volume?

Back 108

Atrial natriuretic peptide

Front 109

Ability of tissue to adjust its own blood flow to match metabolic demand for O2, nutrients, waste removal.

Back 109

Autoregulation

Front 110

What 2 types of stimuli cause autoregulatory changes to blood flow?

Back 110

Physical (hot/cold), chemical (oxygen)

Front 111

Alternate expansion/elastic recoil of artery wall w/ each heartbeat.

Back 111

Pulse

Front 112

Which artery is most commonly used to feel pulse? Normal resting pulse range?

Back 112

Radial. 70-80 BPM.

Front 113

Rapid resting heart/pulse rate (>100 bpm)

Back 113

Tachycardia

Front 114

Slow resting heart/pulse rate (<60 bpm)

Back 114

Brachycardia

Front 115

Pressure exerted by blood on artery wall when L ventricle undergoes systole then diastole. Clinically, usually measured in which artery?

Back 115

Blood pressure. Brachial a.

Front 116

Difference b/w systolic vs. diastolic pressure. Usually 40mmHg.

Back 116

Pulse pressure

Front 117

Inadequate cardiac output that results in failure of CV system to deliver oxygen, nutrients to meet cell metabolic needs. Results in cellular dysfunction, cellular metabolism abnormal & cell death.

Back 117

Shock

Front 118

What are 4 types of shock?

Back 118

Hypovolemic, cardiogenic, vascular, obstructive.

Front 119

Type of shock due to decreased blood volume. Sudden hemmorhage, body fluid loss, dehydration.

Back 119

Hypovolemic shock

Front 120

Type of shock due to poor heart function. Associated w/ heart attack which causes ischemia, valve problems, arythmia.

Back 120

Cardiogenic shock

Front 121

Type of shock due to inappropriate vasodilation.

Back 121

Vascular shock

Front 122

Type of vascular shock due to allergies.

Back 122

Anaphylactic shock

Front 123

Type of vascular shock due to head trauma damaging CV centre.

Back 123

Neurogenic shock

Front 124

Type of vascular shock from bacterial toxins that produce vasodilation. Most common - 100,000 deaths/yr US.

Back 124

Septic shock

Front 125

Type of shock due to obstruction of blood flow. Ex, pulmonary embolism.

Back 125

Obstructive shock

Front 126

What are 4 homeostatic responses to shock?

Back 126

Activation of renin-angiotensin-aldosterone system, ADH secretion, sympathetic NS activation, release local vasodilators.

Front 127

What are signs/symptoms of shock?

Back 127

Clammy cool pale skin, tachycardia, weak rapid pulse, sweating, hypotension (systolic pressure < 90mmHg), altered mental status, decreased urine output, thirst, acidosis.

Front 128

Aorta is divided into what 3 sections?

Back 128

Ascending, arch of aorta, descending (thoracic, abdominal)

Front 129

All systemic veins flow into what 3 veins which empty into R atrium?

Back 129

Superior/inferior venae caveae, coronary sinus

Front 130

From which organs does the hepatic portal circulation collect blood?

Back 130

Veins of pancreas, spleen, stomach, intestines, gallbladder.

Front 131

The GI tract drains blood into ___ vein of ___ (organ) before it returns to heart.

Back 131

Hepatic portal vein. Liver.

Front 132

A portal system carries blood b/w 2 ___. In the hepatic portal circulation, it is from ___ to ___.

Back 132

Capillary networks. Capillaries GI tract. Sinusoids liver.

Front 133

Hepatic portal circulation enables nutrient utilization & ___ by liver.

Back 133

Blood detoxification

Front 134

What 2 veins unite to form the hepatic portal vein? Which vein also receives blood from inferior mesenteric vein?

Back 134

Superior mesenteric, splenic vv. <-- receives blood from inf.

Front 135

Liver receives nutrient-rich deoxygenated blood from ___ & oxygenated blood from ___. These 2 mix in sinusoids & liver is drained via hepatic veins.

Back 135

Hepatic portal vein. Hepatic artery.

Front 136

Which 2 arteries are the only ones that carry deoxygenated blood?

Back 136

R/L pulmonary arteries

Front 137

Resistance to blood is low in pulmonary arteries due to what variables in diameter, BV wall thickness, elastic tissue?

Back 137

Larger diameter. Thinner wall. Less elastic tissue.

Front 138

Why is pulmonary edema usually prevented?

Back 138

Normal pulmonary capillary hydrostatic pressure is lower than systemic capillary hydrostatic pressure.

Front 139

What are 6 changes associated w/ aging & CV system?

Back 139

Loss of extensibility of aorta, reduced size cardiac mm fiber, loss of cardiac mm strength, reduced cardiac output, decline in max HR, increased systolic BP.

Front 140

What 3 CV pathologies increase w/ age?

Back 140

Coronary artery disease, congestive heart failure, arteriosclerosis.