Lecture 13 - Blood Vessels

Question 1

What are the three major types of blood vessels?

Answer 1

Arteries
Capillaries
And veins

Question 2

Arteries

Answer 2

Carry blood away from heart

In systemic circulation the carrry oxygenate blood
In pulmonary circulation carry deoxygenated

Question 3

Veins

Answer 3

Carry blood toward heart

In systemic circulation the carrry deoxygenated blood
In pulmonary circulation carry oxygenated

Question 4

Capilaries

Answer 4

Can directly exchange gases and nutrients with tissues o meet cellular demands

Connect arterioles an venules

Question 5

What are the three walls of blood vessels?

Answer 5

Tunica intima (endothelium)

Tunica media (smooth muscle and elastin)

Tunica externa (loosely woven collagen fibers)

Question 6

Tunica intima

Answer 6

reduces friction between the vessel walls and blood.

Question 7

Tunica media

Answer 7

controls vasoconstriction and vasodilation of the vessel.

Question 8

Tunica external

Answer 8

protects, reinforces, and anchors the vessel to
surrounding structures.

Question 9

Elastic/conducting arteries

Answer 9

contain large amounts of elastin, allowing these vessels to withstand the pressure changes of the cardiac cycle

Question 10

Muscular/distributing arteries

Answer 10

deliver blood to specific body organs and have the greatest proportion of tunica media of all vessels, making them more active in vasoconstriction.

Question 11

Arterioles

Answer 11

smallest arteries and regulate blood flow into capillary beds through vasoconstriction and vasodilation.

Question 12

Continuous capillaries

Answer 12

most common and allow passage of fluids and small solutes.

Question 13

Fenestrated capillaries

Answer 13

more permeable to fluids and solutes than continuous capillaries.

helps with absorption in the small intestines and filtration in the kidneys.

Question 14

Sinusoid capillaries

Answer 14

leaky capillaries that allow large molecules to pass between the blood and surrounding tissues, such as in the liver, spleen or bone marrow.

Question 15

Anastomosis

Answer 15

connection between blood vessels that supply blood to the same region of the body.

allow blood to have alternative routes to reach tissues and return to heart, in case one blood vessel is damaged or blocked.

Question 16

Metarterioles

Answer 16

unique feature of the circulatory system around the intestines

A cuff of smooth muscle called a precapillary sphincter surrounds each capillary and acts as a valve to regulate blood flow into the capillary or keep the blood in thoroughfare channels.

Question 17

Venules

Answer 17

formed where capillaries converge and allow fluid and white blood cells to move easily between the blood and tissues.

Join to form veins

Question 18

Lumen

Answer 18

Space in middle o blood vessel where blood passes

Question 19

Blood flow

Answer 19

volume of blood flowing through a vessel, organ, or the entire circulation in a given period and may be expressed as mL/min.

Question 20

Blood pressure

Answer 20

the force per unit area exerted by the blood against a blood vessel wall and is expressed in millimeters of mercury (mmHg).

Question 21

Resistance

Answer 21

measure of the friction between blood and the blood vessel walls.

related to blood viscosity, blood vessel length, and blood vessel diameter.

Question 22

Why happen to blood flow when blood pressure increases?

Answer 22

Blood flow increases

Question 23

What happen to blood flow when resistance increases?

Answer 23

Blood flow decreases

Question 24

Peripheral circulation

Answer 24

refers to circulation in all of the blood vessels outside of the heart and coronary vessels.

Question 25

Peripheral resistance

Answer 25

most important factor influencing local blood flow.

Vasoconstriction or vasodilation can dramatically alter local blood flow, while systemic blood pressure remains unchanged.

Question 26

Systemic blood pressure

Answer 26

highest in the aorta and declines throughout the pathway until it reaches 0 mmHg in the right atrium.

Question 27

Arterial blood pressure

Answer 27

relatively high because the arteries close to the heart can be stretched and a large volume of blood is forced into them at during ventricular systole.

Question 28

Diastolic pressure

Answer 28

occurs when the ventricles enter diastole, the aortic valve closes, and the walls of the aorta recoil

maintains pressure at 70-80 mmHg, so that blood continues to flow forward into the smaller vessels.

Question 29

Pulse pressure

Answer 29

difference between diastolic and systolic pressure

Question 30

Capillary blood pressure

Answer 30

is low, ranging from 15–40 mm Hg, which protects the capillaries from rupture but still adequate to ensure exchange between blood and tissues.

Question 31

Venous blood pressure

Answer 31

is low, not pulsatile, and changes very little during the cardiac cycle, reflecting cumulative effects of peripheral resistance.

Question 32

Hypertension

Answer 32

High blood pressure

Increase in systolic/ diastolic pressure

Question 33

Hypotension

Answer 33

Low blood pressure

Due to individual variation, only concern if blood flow to tissues becomes inadequate

Question 34

Capillary blood pressure

Answer 34

low, ranging from 15–40 mm Hg, which protects the capillaries from rupture but is still adequate to ensure exchange between blood and tissues.

Question 35

Venous blood pressure

Answer 35

low, not pulsatile, and changes very little during the cardiac cycle, reflecting cumulative effects of peripheral resistance.

Question 36

Circulatory shock

Answer 36

any condition in which blood volume is inadequate and cannot circulate normally, resulting in blood flow that cannot meet the needs of a tissue.

Question 37

Hypovolemic shock

Answer 37

results from a large-scale loss of blood

It may be characterized by an elevated heart rate and intense vasoconstriction.

Question 38

Vascular shock

Answer 38

occurs with normal blood volume but extreme vasodilation, resulting in poor circulation and a rapid drop in blood pressure.

Question 39

Transient vascular shock

Answer 39

due to prolonged exposure to heat, such as while sunbathing, resulting in vasodilation of cutaneous blood vessels.

Question 40

Cardiogenic shock

Answer 40

occurs when the heart is too inefficient to sustain normal blood flow