Lecture 4 Cardio

Question 1

Entire peripheral vascular system is lined with ___

Answer 1

endothelial cells

Question 2

Capillaries are ONLY ___

Answer 2

Endothelial cells

Question 3

Other peripheral vascular vessels (other than capillaries) have varying amounts of ___ and ___

Answer 3

connective tissue and vascular smooth muscle

Question 4

Aorta and large systemic arteries serve primarily as conduits to… and the resistance they offer to blood flow is ___

Answer 4

move blood from the L ventricle to more distant parts of the peripheral vascular system

low

Question 5

During systole, the amount of blood entering the aorta from the left ventricle is ___ than the amount leaving the aorta toward the peripheral arteries

Answer 5

greater

Question 6

During systole, the BP in the aorta…

Answer 6

increases and its volume increases (greater amount of blood entering than leaving)

Question 7

Max pressure achieved during systole is called

Answer 7

systolic pressure (SP)

Question 8

As the ventricle relaxes and blood is no longer flowing into the aorta, the aortic pressure __ because …

Answer 8

falls because blood is continuing to leave the aorta toward the peripheral vascular network

Question 9

As the ventricle relaxes, the aortic pressure will continue to decrease until the

Answer 9

aortic valve opens at the beginning of the next systole

Question 10

The min pressure in the aorta before ejection begins is called ___

Answer 10

diastolic pressure

Question 11

The difference between the peak systolic pressure and the minimum diastolic pressure is called the ___

Answer 11

pulse pressure

Question 12

Mean arterial pressure in the CENTRAL AORTA can be estimated by the equation:

Answer 12

mean arterial pressure (MAP) = DP+ 1/3 PP

Question 13

The magnitude of the pulse pressure is determined by:

Answer 13

1. amount of blood ejected by the ventricle per beat (stroke volume)
2. rate of ejection of blood from the ventricle
3. compliance of the arterial system

Question 14

what is compliance?

Answer 14

indicates how easily an elastic structure can be stretched

compliance = delta volume/delta pressure

change in volume divided by change in pressure

Question 15

Vascular resistance is determined by the

Answer 15

arterioles

Question 16

Vascular resistance depends largely on the

Answer 16

4th power of the radius of the blood vessel through which the blood is flowing

Question 17

Vascular smooth muscle exhibits ___ that sets the baseline level of vascular constriction

Answer 17

intrinsic tone

Question 18

Baseline tone in vascular smooth muscle can be increased or decreased by…

Answer 18

neurotransmitters or other external factors

Question 19

What is active hyperemia?

Answer 19

increased blood flow as a result of increased metabolic activity

Question 20

Active hyperemia is a result of the …

Answer 20

production or loss of certain materials in the immediate vicinity or within the vascular bed

examples: decreased O2, increased CO2, adenosine, or potassium

Question 21

What is flow autoregulation?

Answer 21

maintenance of blood flow in the face of changes in the mean arterial pressure

Question 22

Flow autoregulation occurs by

Answer 22

the same mechanism as active hyperemia - production or loss of certain materials in the immediate vicinity or within the vascular bed

Question 23

increases in sympathetic nerve activity, through the release of norepinephrine, cause ___ by…

Answer 23

cause vasoconstriction by activating alpha-adrenergic receptors

Question 24

The sympathetic nerves normally exhibit some degree of ___ which produces some degree of ___

Answer 24

vascular tone

vascular constriction

Question 25

Increasing the amount of sympathetic discharge further increases the ___ while decreasing the sympathetic discharge ___ the smooth muscle and produces ____

Answer 25

vasoconstriction relaxes; vasodilation

Question 26

The effects of sympathetic discharge occur ___ and not useful in controlling blood flow into a ____

Answer 26

throughout the body specific organ bed

Question 27

The most common use of sympathetic control occurs during...

Answer 27

regulation of arterial blood pressure

Question 28

Parasympathetic activity plays no important role in...

Answer 28

vascular smooth muscle activity

Question 29

Noncholinergic, nonadrenergic autonomic neurons release ___ which is a ___ these are important in the control of..

Answer 29

nitric oxide vasodilator blood flow in the GI system and in the penis (mediate erection)

Question 30

Several __ play important roles in controlling vascular smooth muscle

Answer 30

hormones

Question 31

Epinephrine (from adrenal medulla) has both__ and __ activity

Answer 31

alpha-adrenergic beta-2 adrenergic

Question 32

Vascular smooth muscle cells contain both ___ and ___ but in most vascular beds, the alpha receptors predominate and the effect of epinephrine is ___ an important exception - in coronary and skeletal vascular smooth muscle, the ___ predominates and the effect of epinephrine is ___

Answer 32

alpha and beta-2 receptors vasoconstriction beta-2 receptors vasodilation

Question 33

Other hormones that directly affect vascular smooth muscle are...

Answer 33

1. angiotensin II (vasoconstrictor) 2. Vasopressin (vasoconsrictor) 3. atrial natiuretic peptide (vasodilator)

Question 34

Vascular endothelial cells are capable of secreting several ___ that diffuse to nearby vascular smooth muscle cells and induce either vasoconstriction or vasodilation

Answer 34

paracrine

Question 35

___ is continuously released from endothelial cells and induces vasodilation

Answer 35

nitric oxide

Question 36

___ is not continuously released as in NO but a number if inputs stimulate its release and trigger vasodilation

Answer 36

prostacyclin (PGI2)

Question 37

___ is an important paracrine vasoconstrictor

Answer 37

endothelin (ET-1)

Question 38

The capillaries are the ..

Answer 38

major site of exchange of nutrients and metabolic end products between the cardiovascular system and the interstitial fluid

Question 39

With capillaries and exchange, the ___ are small and this exchange is efficient in that it occurs rapidly with relatively small ___

Answer 39

diffusion distances concentration differences

Question 40

A typical capillary is a?

Answer 40

thin-walled tube of endothelial cells one layer thick resting on a basement membrane without surrounding smooth muscle of elastic tissue.

Question 41

Endothelial cells are not ...

Answer 41

attached tightly to one another but are separated by intercellular clefts

Question 42

capillary blood flow is dependent on the state of

Answer 42

contraction or relaxation of upstream arterioles

Question 43

Some capillary networks have ___ interposed between the arterioles and the capillaries

Answer 43

metasterioles

Question 44

____ control blood flow from the metarterioles into the capillaries and they ___ or ___ in response to local metabolites

Answer 44

precapillary sphincters contract or relax

Question 45

Blood flow in capillaries is...

Answer 45

much less than that occurring in the arterioles

Question 46

At EACH LEVEL of the circulatory system... (equation)

Answer 46

V = F/A V=blood flow velocity F = blood flow A = total cross sectional area at THAT LEVEL of the circulatory system

Question 47

Except in the brain, ___ is the only important means of exchange of materials at the capillary level

Answer 47

diffusion

Question 48

____ substances (O2, CO2) easily diffuse through the capillary plasma membrane

Answer 48

lipid-soluble

Question 49

Ions and polar molecules pass through ____ in the endothelial lining

Answer 49

small water-filled channels

Question 50

Only small amount of ___ get through the small water channels in most capillary beds

Answer 50

protein

Question 51

No proteins get through___ by ___ whereas most proteins get through the ___ by ____

Answer 51

No proteins get through brain capillaries by diffusion whereas most proteins get through the liver capillaries by diffusion

Question 52

The sequence of movement of a nutrient is..

Answer 52

from the blood plasma through the capillary wall into the interstitial fluid and then into the cell.

Question 53

Since cells are continually using nutrients, there is always an ____ between the plasma and the interior of the cell

Answer 53

overall concentration gradient

Question 54

___ moves across the capillary wall

Answer 54

protein-free plasma

Question 55

The purpose of bulk flow is not the ___ or the ___ but accomplishes the goals of ___

Answer 55

The purpose of bulk flow is not the delivery of nutrients or the removal of metabolic end products but accomplishes the goals of distributing (or redistributing) the extracellular fluid

Question 56

Movement of fluid across the capillary wall is governed by:

Answer 56

Starlings law of the Capillary

Question 57

Net filtration pressure =

Answer 57

(Pc-Pif) - (Pi p - Pi if) P c - Pi if - P if - Pi p like, what??

Question 58

In systemic capillary beds, there is a (describe movement):

Answer 58

net movement of fluid OUT of the capillaries at the arterial end and a net movement of fluid INTO the capillaries at the venous end

Question 59

In the pulmonary capillaries, the same concepts (as with systemic) apply but the magnitude of the forces involved in the process is different. The end result is that...

Answer 59

normally net reabsorption occurs along the entire length of pulmonary capillaries and is a result of the lower BP in the pulmonary system.