Circ/martini

Front 1

The walls of areteries and veins contain 3 distinct layers. What are they?

Back 1

1. Tunica intima
2. Tunica media
3. Tunica externa

Front 2

In general, the walls of arteries are thicker than those of veins. The tunica media of an artery contains more smooth muscle and elastic fibers than does that of a vein. TRUE/FALSE

Back 2

TRUE.

Front 3

What are elastic arteries?

Back 3

They are large vessels with diameters up to 2.5 cm. They transport large volumes of blood away from the heart.

Front 4

What is a muscular artery?

Back 4

They are medium sized arteries or distribution arteries, to skeletal muscles and the bodys organs. A typical muscular artery has a lumen diameter of app. 0.4 cm.

Front 5

Give several examples of muscular arteries/

Back 5

1. carotid
2.brachial
3.mesenteric
4. femoral.

Front 6

A typical capillary consists of an endothelial tube inside a delicate basal lining(lamina), neither a tunica media nor externa is present. The average diameter is app. 8um(close to that of a single RBC). TRUE/FALSE

Back 6

TRUE.

Front 7

What are the 2 types of capillaries?

Back 7

1. Continuous
2. Fenestarted

Front 8

What is the general pathogenesis of plaque formation?

Back 8

1. When cholesterol levels are chronically elevated, cholesterol rich lipo-proteins remain in the circulation.
2.Circulating monocytes remove them from the bloodstream, and these monocytes become filled with lipid droplets.(Foam cells)
3. These foam cells attach to the endothelial walls of blood vessels, where they release cytokines.
4. These growth factors stimulate the division of smooth muscle cells near the tunica intima thickening the vessel wall.

.

Front 9

Estrogens may slow plaque formation, which could account for the lower incidence of coronary disease. TRUE/FALSE

Back 9

TRUE.

Front 10

What is a continuous capillary?

Back 10

The endothelium is a complete lining. In a large continuous artery several endothelial cells may represent the thickness. In a small one, one cell may be represented.
They permit the passage of water, small solutes, and lipid soluble materials into the surrounding interstitial fluid.(Blood brain barrier0

Front 11

What is a fenestrated capillary?

Back 11

These capillaries contain pores that penetrate the endothelial lining. They permit rapid exchange of water and solutes as large as small peptides between plasma and interstitial fluid. They are found in the hypothalamus, pituitary pineal and thyroid glands.

Front 12

What is a sinusoid?

Back 12

They resemble fenestrated capillaries that are flattened and irregularly shaped. They have gaps between adjacent endothelial cells. Permit the free exchange of water and solutes as large as plasma proteins between blood and interstitial fluid.

Front 13

What are arteriovenous anastomoses?

Back 13

They are direct connections between arterioles and venules. Blood can at times bypass the capillary bed and flow directly into the venous circulation.

Front 14

An average venule has an internal diameter of roughly 20um. TRUE/FALSE

Back 14

TRUE.

Front 15

What are capacitance vessels?

Back 15

veins are capacitance vessels, which expand easily. They can accommodate large changes in blood volume.

Front 16

Capillary blood flow is determined by the interplay between pressure(P) and resistance(R). TRUE?FALSE

Back 16

TRUE. The heart must must overcome the resistance of blood flow. Increased pressure yields increased flow, and inversely proportional to resistance(increased resistance yields decreased flow.
In formulary terms;
Flow is proportional to the difference of pressure over resistance.

Front 17

What is Capillary hydrostatic pressure?

Back 17

It is the pressure within capillary beds. Pressures range from 35mm/Hg to 18mm/Hg.

Front 18

The pressure gradient from the venules to the right atrium is only about 18mm/Hg. TRUE/FALSE

Back 18

TRUE.

Front 19

Increasing the length of a blood vessel increases friction. TRUE/FALSE

Back 19

TRUE. If 2 vessels are equal in diamter, but one is twice as long as the other, the longer vessel offers twice as much resistance. But for two vessels of equal, one twice the diameter of the other, the narrower one offers, 16 times as much resistance to blood flow.
In formulary terms;
Resistance is proportional to the length over the 4th power of the radius.

Front 20

What is viscosity/

Back 20

Is resistance to flow caused by interactions among molecules and suspended materials in a liquid.(water has a viscosity of 1)

Front 21

What is turbulence?

Back 21

High flow rates, irregular surfaces, and sudden changes in vessel diamter upset the smooth flow of blood creating eddies and swirls.

Front 22

What is "pulse"?

Back 22

A pulse is a rhythmic pressure oscillation that accompanies each heart beat. The difference between systolic and diastolic pressures is the pulse pressure.

Front 23

What is "mean arterial pressure"?

Back 23

It is used to report a single blood pressure value. It is calculated by adding one/third of the pulse pressure to the diastolic pressure;

MAP= diastolic pressure+ pulse pressure
---------------
3
For a systolic pressure of 120mm/Hg and a diastolic pressure of 90mm/, the MAP can be calculated;

MAP= 90+ 120-90
------- = 90 + 10 = 100mm/HG 3
3

Front 24

What is a concentration gradient?

Back 24

Diffusion is the net movement of ions or molecules from an area where their concentration is higher to an area where their concentration is lower. The difference between the higher and lower concentrations represents a concentration gradient.

Front 25

Plasma proteins are normally unable to cross the endothelial lining anywhere except in sinusoids, such as those of the liver. TRUE/FALSE

Back 25

TRUE.

Front 26

What is Osmotic pressure?

Back 26

It is an indication of the force of osmotic water movement, the pressure that must be applied to prevent osmotic movement across a membrane. The higher the solute concentration of a solution, the greater the solutions osmotic pressure.
The osmotic pressure of the blood is also called blood colloid osmotic pressure(BCOP), because only suspended proteins are unable to cross the capillary walls.

Front 27

What is "net hydrostatic pressure"?

Back 27

This pressure tends to push water and solutes out of capillaries and into the interstitial fluid.
It is the difference between the "capillary hydrostsic pressure and the "hydrostatic pressure of the interstitial fluid(IHP).

Front 28

What is "net colloid osmotic pressure"?

Back 28

It tends to pull water and solutes into a capillary from the interstitial fluid.
It is the difference between;
blood colloid osmotic pressure(app. 25mm/Hg) and the interstitial fluid colloid osmotic pressure(ICOP).

Front 29

What is "net filtration pressure"?

Back 29

It is the difference between the net hydroststic pressure and the net osmotic pressure. When this value is positive, it indicates that fluid will tend to move out of the capillary and into interstitial fluid. At the venous end of the capillary, the net filtration pressure will be minus, and this indicates that fluid tends to move into the capillary, that is ,reabsorption is occurring.

Front 30

If the CHP(capillary hydroststic pressure) rises or the BCOP(blood colloid osmotic pressure) declines, fluid moves out of the blood and builds up in peripheral tissues, acondition of edema exists. TRUE/FALSE

Back 30

TRUE.

Front 31

List three factors that influence tissue perfusion?

Back 31

1. Cardiac output
2. Peripheral resistance
3. Blood pressure

Front 32

List 6 factors that promote local vasodilation.

Back 32

1. Decreased tissue O2 levels or increased CO2 levels.
2. Lactic acid
3. Nitric oxide(NO)
4.Rising levels of K+ ions or H+ ions in the interstitial fluid.
5. Histamine
6. Elevated temperature.

Front 33

List several compounds that cause local vasoconstriction.

Back 33

1.Prostaglandins/Thromboxanes-released by activated platelets and WBC.
2. Endothelins

Front 34

The neurons innervating peripheral blood vessels in most tissues are adrenergic, that is they release the neurotransmitter norepinephrine(NE). The response to this is the stimulation of smooth muscle in the walls of arterioles, producing vasoconstriction. TRUE/FALSE

Back 34

TRUE.

Front 35

The most common vasodilator synapses are cholinergic, their synoptic knobs release ACh. ACh stimulates endothelial cells in the area to release NO, resulting in vasodilation. TRUE/FALSE

Back 35

TRUE. Other vasodilator synapses are "nitroxidergic", the synoptic knobs release NO as a neurotransmitter.

Front 36

The resistance of a maximally constricted arteriole is roughly 80X that of a fully dilated arteriole. TRUE/FALSE

Back 36

TRUE.

Front 37

What is the Valsalva maneuver?

Back 37

`Exhaling forcefully against a closed glottis, causes reflexive changes in blood pressure and cardiac output due to compression of the aorta and venae cavae.

Front 38

A steep rise in CSF CO2 levels will trigger the vasodilation of cerebral vessels, but will produce vasoconstriction in most other organs. the result is increased blood flow, and increased O2 delivery to the brain. TRUE/FALSE

Back 38

TRUE.

Front 39

Give some examples of how the endocrine system provides both short and long term regulation of cardiovascular performance.

Back 39

E. and NE from the adrenal medulla stimulate CO and peripheral vasoconstriction. Other hormones important in CO regulation are; ADH/Angiotensin 11/EPO/ANP and BNP.

Front 40

What is angiotensin 11?

Back 40

This appears in the blood after the release of the enzyme renin by juxtaglomerular cells, in response to a fall in blood pressure.
Renin converts angiotensinogen, a plasma protein produced by the liver to angiotensin 1. In pulmonary capillaries, angiotensin converting enzyme(ACE) then modifies angiotensin 1 to angiotensin 11, an active hormone.