Blood vessels

Question 1

What are the three main vessel types?

Answer 1

Veins, Arteries, Capillaries

Veins carry deoxygenated blood to the heart, arteries carry oxygenated blood away from the heart, and capillaries facilitate gas exchange.

Question 2

What are the three layers of artery and vein structure and what is the structure of each?

Answer 2

Tunica Interna, Tunica Media, Tunica Externa

Tunica Interna: lines inside blood vessels & repels WBC and RBC from sticking; Tunica Media: middle layer with muscle for contraction; Tunica Externa: outer layer anchoring the vessel.

Question 3

What is a key structural difference between arteries and veins?

Answer 3

Arteries are diverging and have a thicker tunica media; veins are converging, contain valves, and have larger lumens.

Question 4

What are the three types of capillaries?

Answer 4

• Fenestrated Capillary
• Continuous Capillaries
• Sinusoids

Fenestrated capillaries have filtration pores, found in kidneys, small intestine, absorption and filtration. continuous capillaries have tight junctions, least permeable. Sinusoids are the most permeable allow albumin and new blood cells

Question 5

How is blood flow regulated to the capillaries?

Answer 5

Capillary beds have precapillary sphincters that open/close to regulate blood flow to tissue. And vasomotion of arterioles.

Question 6

What distinguishes pulmonary arteries from other arteries?

Answer 6

They carry deoxygenated blood.

Question 7

What distinguishes pulmonary veins from other veins?

Answer 7

They carry oxygenated blood.

Question 8

What is the function of venous valves? What can happen if these fail?

Answer 8

They move blood in one direction and prevent backflow/pooling.

Failure = Varicose veins

Question 9

What type of vessel contains most of your circulating blood?

Answer 9

Veins.

Question 10

Which vessel type would remain open without blood flowing in it?

Answer 10

Artery.

Question 11

What is blood flow?

Answer 11

Amount of blood through an organ, tissue, or vessel.

Question 12

What is blood pressure and what three factors influence it?

Answer 12

Force of blood on a vessel; influenced by cardiac output, blood volume, and resistance.

Question 13

What is resistance in the context of blood flow?

Answer 13

Resistance of flow due to friction; sources include blood viscosity, vessel length, and vessel radius.

Question 14

What happens to resistance as vessel length increases?

Answer 14

Resistance increases.

Question 15

How does blood pressure change from arteries to capillaries to veins?

Answer 15

Blood pressure decreases with increased distance from the heart.

Question 16

What are the determinants of velocity in the three vessel types?

Answer 16

Distance traveled, radii, number of vessels in cross-section.

Question 17

Why do arteries pulse?

Answer 17

Increased blood flow during systole causes artery walls to expand.

Question 18

What is systolic pressure?

Answer 18

Pressure during ventricular contraction.

Question 19

What is diastolic pressure?

Answer 19

Pressure during ventricular relaxation.

Question 20

How is blood pressure controlled locally?

Answer 20

• Metabolic
• Myogenic
• Vasoactive chemicals

Includes factors like vasodilators such as histamine.

Question 21

What is reactive hyperemia?

Answer 21

Decreased blood flow followed by increased blood flow when a body part falls asleep.

Question 22

What is angiogenesis?

Answer 22

Creating new blood vessels.

Question 23

What is a normal blood pressure reading?

Answer 23

120/80.

Question 24

What defines hypotension?

Answer 24

Low resting blood pressure without a specific number.

Question 25

What defines hypertension?

Answer 25

Blood pressure greater than 130/80 at rest.

Question 26

What are the mechanisms of substance exchange in capillaries?

Answer 26

* Diffusion * Transcytosis * Filtration & Reabsorption ## Footnote Diffusion includes lipid-soluble substances; transcytosis involves transport of large molecules.

Question 27

What are three causes of edema?

Answer 27

* Increased capillary filtration * Decreased capillary reabsorption * Obstructed lymphatic drainage.

Question 28

What are the five mechanisms that aid venous return?

Answer 28

* Pressure gradient * Gravity/Vasomotion * Skeletal muscle pump * Thoracic (respiratory) pump * Cardiac suction.

Question 29

How does exercise alter venous return?

Answer 29

Increases heart rate, blood flow, skeletal muscle pump, and thoracic pump.

Question 30

What is circulatory shock?

Answer 30

Cardiac output insufficient for body needs.

Question 31

What is a TIA?

Answer 31

Brief episodes of cerebral ischemia, warning of impending stroke.

Question 32

What is a stroke (CVA)?

Answer 32

Sudden death of brain tissue due to ischemia.

Question 33

Why is an air embolism dangerous?

Answer 33

Bubbles can block vessels.

Question 34

What is ascites?

Answer 34

Abnormal distension due to serous fluid buildup in the peritoneal cavity.

Question 35

What are the different types of veins?

Answer 35

* Post capillary venules * Muscular venules * Medium venules * Large veins.

Question 36

What are the types of circulatory shock?

Answer 36

* Hypovolemic shock * Obstructed venous return shock * Venous pooling shock * Neurogenic shock.

Question 37

What is the physiological purpose of vasoreflexes

Answer 37

To raise/lower blood pressure throughout the body and selectively, modify perfusion by rerouting blood from one region to another

Question 38

Why does exercise increase Venus return?

Answer 38

Heartbeat, faster and harder, increasing cardiac output, and pressure

Question 39

How is increased muscle perfusion during exercise accomplished?

Answer 39

Arterial dilate from EPI/ NOR Blood diverted from kidneys and digestive track to working muscles.

Question 41

What is the order through which blood would pass beginning with blood entering the systemic system after exiting the heart?

Answer 41

Conducting arteries, distributing arteries, resistance arteries, arterioles, capillaries, post capillary venules, muscular venules, medium veins, Venous sinuses, large veins