Part 1: The Systemic Circulation

Question 1

What happens to pulse pressure as you move further from the heart?

Answer 1

It widens (increases - larger difference between systolic and diastolic in vessels further from the body)

Question 2

Do capillaries and veins have a pulse pressure?

Answer 2

No

Question 3

Where is the greatest decrease in arterial pressure?

Answer 3

across the arterioles

Question 4

What plays a larger role in sculpting the mean arterial pressure?

Answer 4

diastolic

Question 5

What happens to the mean arterial pressure as you move throughout the circulatory system?

Answer 5

it decreases

Question 6

Which pressure increases further from the heart, systolic or diastolic?

Answer 6

Systolic

DIastolic DEcreases

Question 7

What are the three components of the vascular wall (both artery and vein)?

Answer 7

1) Tunica Intima
2) Tunica Media
3) Tunica Adventitia

Question 8

What cells line blood vessels and lymphatics?

Answer 8

endothelial cells

Question 9

How does arterial tunica intima differ from venous tunica intima?

Answer 9

It has an internal elastic lamina (IEL)

Question 10

What is the tunica intima?

Answer 10

subendothelial connective tissue

Question 11

How does venous tunica media differ from arterial?

Answer 11

It has fewer smooth muscle cells and NO external elastic lamina

Question 12

What is the tunica adventitia?

Answer 12

mostly connective tissue with some smooth muscle cells and vasa vasorum

Question 13

What do arteries have that veins do not?

Answer 13

1) elastic lamina
2) more smooth muscle
3) less connective tissue

Question 14

What layer of the vascular wall is more pronounced in veins?

Answer 14

tunica adventitia

Question 15

Rank these in order of increasing compliance:

elastic lamina, smooth muscle, collagen

Answer 15

collagen < smooth muscle < elastic lamina (highest compliance)

Question 16

Name the 3 types of capillaries

Answer 16

1) Continuous (tight junctions between cells; no holes)
2) Fenestrated (holes)
3) Discontinuous (sinusoidal) (endothelial cells are separated by wide spaces)

Question 17

Where are continuous capillaries found?

Answer 17

muscle, connective tissue

Question 18

Where are fenestrated capillaries found?

Answer 18

kidney, intestine

Question 19

Where are discontinuous capillaries found?

Answer 19

liver, bone marrow, spleen

Question 20

According to the LaPlace relationship, what ratio should be high to achieve the greatest control of vessel diameter and blood flow?

Answer 20

Wall thickness/lumen diameter

thick walls with thin diameter aka arteries

Question 21

What has the highest wall thickness/lumen diameter ratio?

Answer 21

pre-capillary sphincters

Question 22

Why do veins regulate volume more than flow or pressure?

Answer 22

because they have relatively small wall thickness/lumen diameter ratio

Question 23

Do lower or higher compliant aortas generate larger pulse pressures (greater difference between systolic and diastolic?)

Answer 23

lower compliant aortas do!

Why? stiffer walls create a higher afterload generating a larger systolic pressure. Diastolic pressure decreases creating larger pulse pressure

Question 24

How do highly compliant vessels generate pressure?

Answer 24

recoil (stiffer, low compliant vessels have less recoil)

Question 25

What is an increase in pulse pressure bad?

Answer 25

it changes afterload in the heart (usually causing more oxygen utilization)

Question 26

What is more dangerous, low or high compliant aorta?

Answer 26

low! creates larger afterload causing the heart to consume more O2

Question 27

What happens to compliance of a blood vessel as blood volume increases?

Answer 27

it decreases because load on the vascular wall is first borne by elastin and smooth muscle (high compliance) at lower volumes and lastly by collagen (low compliance) at huger volumes.

Question 28

What clinical danger do you need to look out for with blood volume expansion?

Answer 28

hypertension

Question 29

What is the importance of an highly compliant aorta?

Answer 29

the recoil that occurs after the aortic valve closes acts as a sort of second pump after systole that maintains constant flow during diastole. NEED TO HAVE HIGH COMPLIANCE

Question 30

What happens to aortic compliance as we age?

Answer 30

it decreases (less elastin (highly compliant) and more collagen (low compliance)

Question 31

What does a decrease in compliance of the aorta result in?

Answer 31

more cardiac work and a larger pulse pressure | afterload likely went up too causing an increase in O2 consumption

Question 32

Younger people get _________ (systolic or diastolic) hypertension

Answer 32

diastolic (D is earlier than S in the alphabet)

Question 33

Older people get __________ (systolic or diastolic) hypertension

Answer 33

systolic because aortic compliance has likely decreased

Question 34

What can an increased pulse pressure lead to?

Answer 34

1) congestive heart failure | 2) can contribute to systolic hypertension, cardiac hypertrophy, aortic distention, low exercise tolerance

Question 35

Because arteries maintain relatively low compliance, they are known as __________ vessels

Answer 35

resistance

Question 36

Conversely, because veins feature high compliance, they are known as __________ vessels

Answer 36

capacitance (meaning they can hold a lot of blood)

Question 37

What happens to the compliance of veins as arterial pressure dramatically increases?

Answer 37

venous compliance decreases | why saphenous vein can be used for coronary artery grafts even though they are morphologically different

Question 38

Where is the pressure pulse going to be the highest?

Answer 38

furthest from the heart (ex: femoral)

Question 39

As compliance decreases, what happens to the pressure pulse?

Answer 39

It INCREASES because it is easier for the energy wave to run quickly down a stiff tube