Introduction to the circulatory system

Question 1

what is the circulatory system

Answer 1

a system made up of the cardiovascular system and the lymphatic system

Question 2

what is the cardiovascular system

Answer 2

made up of the arterial system, the heart, and the venous system (function = distribute gases and other molecules for nutrition, growth and repair)

Question 3

Pulmonary circulation

Answer 3

right side of heart → lungs → left side of heart

Question 4

Systemic circulation

Answer 4

left side of heart → capillary beds of organs and tissues → right side of heart

Question 5

Endocardium(internal):

Answer 5

continuous with endothelium of blood vessels connecting with the heart

Question 6

Epicardium(external):

Answer 6

visceral serous pericardium

Question 7

Myocardium(middle):

Answer 7

cardiac muscle layer

Question 8

conduction system of the heart 1

Answer 8

Electrical impulse starts at SA node - atria contract

Question 9

conduction system of the heart 2

Answer 9

Impulse travels to AV node at AV septum

Question 10

conduction system of the heart 3

Answer 10

Impulse travels down left and right bundles in the IV septum

Question 11

conduction system of the heart 4

Answer 11

Impulse spreads out to myocardium through conducting fibers - ventricles contract

Question 12

The arterial system

Answer 12

Each artery (and its branches) carries oxygenated blood to a territory

Question 13

Tunica intima(internal):

Answer 13

endothelium

Question 14

Tunica media(middle):

Answer 14

smooth muscles and elastic fibres

Question 15

Tunica adventitia(external):

Answer 15

connective tissue

Question 16

VASODILATION

Answer 16

Relaxation of the smooth muscle and widening of the lumen to INCREASE blood flow to the organ/tissue supplied

Question 17

VASOCONSTRICTION

Answer 17

Contraction of smooth muscle to REDUCE blood flow to the organ/tissue supplied

Question 18

Sympathetic tone:

Answer 18

background, low level contraction of smooth muscle in arterioles
- Due to tonic production of action potentials to arterioles by sympathetic nerves

Question 19

anastomoses:

Answer 19

where arteries connect to each other without an intervening capillary network

Question 20

what else do anastomoses do?

Answer 20

• Provides alternative routes for blood flow to supply cells distal to an arterial occlusion
• Each alternate route given by an anastomosis is called acollateral

Question 21

End artery:

Answer 21

the only arterial blood supply to a given area of the body

Question 22

infarction:

Answer 22

irreversible cell death due to hypoxia caused by loss of arterial bloody supply

• Result of untreated occlusion of an end artery

Question 23

what do the left and right coronary arteries do?

Answer 23

supply blood to the heart muscle

Question 24

what do branches of the arch of the aorta do?

Answer 24

supply blood to the upper limbs and head

Question 25

what does the descending aorta supply

Answer 25

thorax and abdomen

Question 26

within the abdomen what does the abdominal aorta branch into

Answer 26

2 common iliac arteries that provide blood to the pelvis and lower limbs

Question 27

what does the venous system do

Answer 27

veins drain deoxygenated blood from a territory

Question 28

How is venous blood pumped back to the heart

Answer 28

through
- venous valves
- skeletal muscle pump
- accompanying veins

Question 29

superficial veins

Answer 29

smaller, run within the superficial fascia, drain into deep veins

Question 30

Deep veins:

Answer 30

larger, run deep to the deep fascia in cavities, often in neurovascular bundles

Question 31

Hepatic portal venous system:

Answer 31

drains venous blood from absorptive parts of the GI tract and associated organs for cleaning

Question 32

Systemic venous system:

Answer 32

drains venous blood from all of the organs and tissues into the superior or inferior vena cavae

Question 33

what does the lymphatic system do?

Answer 33

Lymphatic capillaries collect tissue fluid (lymph)

Question 34

describe lymphatic circulation 1

Answer 34

Lymphatics carry lymph through lymph nodes

Question 35

describe lymphatic circulation 2

Answer 35

2. Eventually lymph is returned into the central veins in the root of the neck

Question 36

ymph from superficial lymphatics →

Answer 36

deep lymphatics

Question 37

Lymph from right lymphatic duct →

Answer 37

right venous angle

Question 38

Lymph from thoracic duct →

Answer 38

left venous angle