Chapter 21 - Blood Vessels and Circulation

Question 1

What do arteries do?

Answer 1

Carry blood away from the heart

Question 2

What are arterioles?

Answer 2

Smallest branches of the arteries that lead to capillary beds

Question 3

What is the function of capillaries?

Answer 3

Location of exchange between blood and interstitial fluid

Question 4

What are venules?

Answer 4

Smaller branches of veins that collect blood from capillaries

Question 5

What is the primary role of veins?

Answer 5

Return blood to the heart

Question 6

What is the tunica intima?

Answer 6

Inner layer of a blood vessel that includes an endothelial lining

Question 7

What does the tunica media contain?

Answer 7

Concentric sheets of smooth muscle

Question 8

What is the tunica externa?

Answer 8

Outer layer of a blood vessel that contains connective tissue

Question 9

How do arteries differ from veins in terms of wall thickness?

Answer 9

Arteries have thicker walls with more smooth muscle and elastic fibers

Question 10

What is a key difference between arteries and veins regarding shape when cut?

Answer 10

Arteries stay circular while veins collapse

Question 11

True or False: Veins have valves to prevent backflow.

Answer 11

True

Question 12

What are elastic arteries?

Answer 12

Largest arteries, closest to the heart, that can stretch and recoil

Question 13

What is elastic rebound?

Answer 13

Walls stretch with increasing pressure during systole and recoil during diastole

Question 14

What are muscular arteries?

Answer 14

Medium-sized arteries with lots of smooth muscle

Question 15

What are arterioles also known as?

Answer 15

Resistance vessels

Question 16

Fill in the blank: Vasoconstriction is the _______ of arterial smooth muscle.

Answer 16

Contraction

Question 17

Fill in the blank: Vasodilation is the _______ of arterial smooth muscle.

Answer 17

Relaxation

Question 18

What do continuous capillaries have?

Answer 18

Complete endothelial lining

Question 19

What are fenestrated capillaries characterized by?

Answer 19

Pores in the endothelial lining

Question 20

What are sinusoids?

Answer 20

Gaps between adjacent endothelial cells

Question 21

What do venules collect?

Answer 21

Blood from capillaries

Question 22

What is a key feature of medium-sized veins?

Answer 22

Have three tunic layers

Question 23

What is the function of venous valves?

Answer 23

Prevent blood from flowing backward

Question 24

What are capacitance vessels?

Answer 24

Veins that are distensible and act as blood reservoirs

Question 25

What determines blood flow (F)?

Answer 25

Pressure (P) and resistance (R)

Question 26

What is the pressure gradient (∆P)?

Answer 26

Pressure difference from one vessel end to the other

Question 27

What is Poiseuille’s Law used for?

Answer 27

To calculate blood flow (Q)

Question 28

What does total peripheral resistance refer to?

Answer 28

The resistance of the entire cardiovascular system

Question 29

What causes vascular resistance?

Answer 29

Friction between blood and vessel walls

Question 30

What is blood viscosity?

Answer 30

Resistance caused by interactions between molecules and suspended materials in blood

Question 31

What is turbulence in blood flow?

Answer 31

Swirling action that disturbs smooth blood flow

Question 32

What is systolic pressure?

Answer 32

Peak arterial pressure during ventricular systole

Question 33

What is diastolic pressure?

Answer 33

Minimum arterial pressure at the end of ventricular diastole

Question 34

What is pulse pressure?

Answer 34

The difference between systolic and diastolic pressures

Question 35

Fill in the blank: Mean arterial pressure (MAP) is calculated by _______.

Answer 35

Diastolic pressure + pulse pressure

Question 36

What defines hypertension?

Answer 36

Abnormally high blood pressure greater than 140/90

Question 37

What is hypotension?

Answer 37

Abnormally low blood pressure

Question 38

What assists venous return to the heart?

Answer 38

Venous valves, muscular pump, and respiratory pump

Question 39

What is capillary exchange?

Answer 39

Chemical and gaseous exchange between blood in capillaries and interstitial fluid

Question 40

What drives filtration in capillaries?

Answer 40

Hydrostatic pressure

Question 41

What is osmosis?

Answer 41

Movement of water across a membrane from lower to higher solute concentration

Question 42

What is bulk flow?

Answer 42

Continuous net movement of water out of capillaries through tissues back to the bloodstream

Question 43

What factors make diffusion efficient?

Answer 43

* Short distances involved * Steeper concentration gradient * Smaller solute size

Question 44

What is capillary filtration?

Answer 44

Water and small solutes are forced across the capillary wall

Question 45

What happens during reabsorption?

Answer 45

Movement of water back into capillaries driven by osmosis