Chapter 21: Circulatory System

Question 1

Types of blood vessels

Answer 1

arteries, arterioles, capillaries, venules, veins

Question 2

Arteries

Answer 2

carry blood away from the heart

Question 3

Arterioles

Answer 3

smallest branches of arteries

Question 4

Capillaries

Answer 4

smallest blood vessels, responsible for material exchange between blood and interstitial fluid

Question 5

Venules

Answer 5

collect blood from capillaries

Question 6

Veins

Answer 6

return blood to heart

Question 7

Where are the largest blood vessels attached?

Answer 7

to the heart

Question 8

Aorta

Answer 8

the largest, elastic artery sends blood from LV to the systemic circulation

Question 9

Pulmonary Trunk

Answer 9

major vein that sends blood from the RV to the pulmonary circulation

Question 10

Differences between arteries and veins

Answer 10

-arteries and veins run side to side
-arteries have thicker walls and higher pressures
-relaxed artery has small, round lumen
-vein typically has a large, flat lumen
-vein endothelium contracts (not so for arteries)
-arteries are more elastic
-veins have valves but arteries do not

Question 11

Smooth muscle tissue structure

Answer 11

long, slender, and spindle-shaped with central nucleus
-no T-tubules, myofibrils or sarcomeres
-scattered myosin fibers
-thin filaments attached to dense bodies, which transmit contractions from cell to cell

Question 12

Smooth muscle control of contractions

Answer 12

-multiunit smooth muscle cells innervated by motor neurons
-visceral smooth muscle cells are not connected to motor neurons
-rhythmic cycles of activity controlled by pacesetter cells

Question 13

Characteristics of capillary beds

Answer 13

aka capillary plexus
-connect one arteriole to one venule
-precapillary sphincters are found and guard entrances to each capillary; opens and closes, causing blood to flow in pulses

Question 14

Thoroughfare channels (metarterioles)

Answer 14

direct connections between arterioles and venules controlled by smooth muscle segments

Question 15

Collaterals

Answer 15

multiple arteries supplying one capillary bed

Question 16

Arterial anastomoses

Answer 16

the fusion of 2 collateral arteries

Question 17

Arteriovenous anastomoses

Answer 17

bypass capillary bed

Question 18

Arteriovenous anastomoses

Answer 18

bypass capillary bed

Question 19

Blood Colloid Osmotic Pressure (BCOP)

Answer 19

reabsorption at the capillary bed
-equal pressure required to prevent osmosis
-caused by blood proteins too large to cross capillary wall

Question 20

Capillary Hydrostatic Pressure

Answer 20

out of capillary

Question 21

Arteries carrying deoxygenated blood

Answer 21

-Pulmonary trunk; receives blood from RV
-Pulmonary arteries; deliver blood to the lungs
-Pulmonary arterioles; branch to capillary networks surrounding alveoli

Question 22

Veins carrying oxygenate blood

Answer 22

-Venules join alveolar capillary networks
-Pulmonary veins arise from the joining of venules

Question 23

Ascending Aorta

Answer 23

leaves the base of the heart and branches into aortic arch

Question 24

Coronary arteries

Answer 24

branch from aortic sinuses to supply blood to the myocardium

Question 25

Aortic arch branches into..

Answer 25

Brachiocephalic trunk, left common carotid artery, and left subclavian artery

Question 26

Descending Aorta

Answer 26

arises from downward turn of the aortic arch
-becomes the thoracic and abdominal aorta

Question 27

Superior Vena Cava

Answer 27

receives blood from head, neck, chest, shoulders, and upper limbs

Question 28

Inferior Vena Cava

Answer 28

collects blood from organs inferior to the diaphragm

Question 29

Hepatic Portal System

Answer 29

subdivision of systemic venous circulation
-detours venous blood from GI tract to liver on the way to the heart

Question 30

What forms the hepatic portal vein

Answer 30

splenic, superior mesenteric, and inferior mesenteric veins

Question 31

What veins merge with the portal vein?

Answer 31

gastric veins

Question 32

What does the portal vein deliver?

Answer 32

glucose and amino acids from the GI tract directly to the liver for storage, metabolic conversion, or excretion before sending deoxygenated blood to the heart