4. CIRCULATORY SYSTEM

Question 1

arteries

Answer 1

taking blood away from the heart
-absorbs and stores pressure to even flow to capillary bed

Question 2

veins

Answer 2

returning blood to the heart

Question 3

lymphatics

Answer 3

thin walled vessels, blind ended
- collect fluid and return it to primary circulatory system

Question 4

endothelial cells

Answer 4

prevent clotting, allow macrophages to infiltrate tissue, help control growth

Question 5

what do endothelial cells secrete?

Answer 5

paracrine factors

Question 6

what pressure does the pulmonary circuit work at?

Answer 6

low pressure

Question 7

what happens if the lungs are at high pressure

Answer 7

edema

Question 8

what is edema?

Answer 8

lungs fill w fluid and no gas exchange can occur

Question 9

what 4 things make up the pulmonary circuit?

Answer 9

pulmonary veins
pulmonary arteries
right atrium
right ventricle

Question 10

what makes up systemic circulation

Answer 10

left atrium
left ventricle
aorta to systemic arteries
systemic veins

Question 11

what pressure does the systemic circuit operate at?

Answer 11

high pressure bc long distances

Question 12

myogenic

Answer 12

contracts spontaneosly

Question 13

autorythmic

Answer 13

controlled by sinoatrial node (pace makers set rythm)

Question 14

right ventricle

Answer 14

delivers blood to polmonary circuit

Question 15

pericardium

Answer 15

fluid filled sac
reduces friction from heart beating (reduces damage)

Question 16

perkinje fibres

Answer 16

conducting systm in ventricles

Question 17

where does contraction of the ventricles start?

Answer 17

at the apex which forces blood up

Question 18

what does the left ventricle do?

Answer 18

muscular-pumps to the systemic circuit

Question 19

what is the endocardium made up of?

Answer 19

endothelium –> squamous cells

Question 20

what is the subendocordial layer

Answer 20

conducting signal for contraction

Question 21

what does the subendocordial layer possess?

Answer 21

modified myocytes, fewer myofibrils, purkinje fibres

Question 22

what are mesothelial cells important for?

Answer 22

fluid secretion (into pericardium)

Question 23

epicardium

Answer 23

outer wall of heart

Question 24

coronary vessels

Answer 24

blood supply to the heart

Question 25

windkessel

Answer 25

elastic resevoir in artery walls for an even flow

Question 26

venules, veins

Answer 26

functions at low pressure acts as volume resevoir

Question 27

velocity =

Answer 27

1/ x-sectional area

Question 28

mesothelium

Answer 28

present in blood vessels in cavity not present when vessel is embedded in tissue/organ

Question 29

artery vs vein

Answer 29

arteries -thick wall and small lumen -more elastic -low compliance veins -have thin wall and large lumen - high compliance

Question 30

elasticity

Answer 30

tendency to return to intial structure thats being distended (recoil)

Question 31

from inside in what are the layers of arteries and veins?

Answer 31

intima endothelium subendothelial layer internal elastic lamina media external elastic lamina adventitia vasa vasorum

Question 32

what is vaso vasorum

Answer 32

like a coronary vessel in heart (but for large blood vessels) - oxygenated + nutrient rich blood delivery

Question 33

why is the adventitia bigger in veins then arteries?

Answer 33

takes up more space in veins to replace area

Question 34

what is intima made up of?

Answer 34

squamous epithelia; loose connective tissue -may have some smooth muscle - fenestrated

Question 35

what is media made of?

Answer 35

concentric layers of helically arranged smooth muscle - reticular fibres and proteoglycans

Question 36

what is adventitia made of?

Answer 36

connective tissue layer, type i collagen , elastic fibres

Question 37

function of the muscular artery

Answer 37

distribution of blood + organs help regulate blood pressure + blood flow

Question 38

muscular artery ; vasoconstriction

Answer 38

smaller diameter

Question 39

muscular artery; vasodilation

Answer 39

larger diameter

Question 40

what does smooth muscle do?

Answer 40

wrap arterioles and metarterioles - regulate blood flow and contribute to blood pressure regulation

Question 41

what is the metarteriole

Answer 41

the terminal arteriole branch before capillary bed

Question 42

relaxed precapillary sphincters

Answer 42

ring of smooth muscle cells relaxed blood flow to capillary beds

Question 43

shunting

Answer 43

temperature regulation (avoid blood going to skin)

Question 44

capillaries

Answer 44

smallest vessel thin wall extensive surface area optimized for exchange

Question 45

pericycle role?

Answer 45

contractile secretes ECM regulates permeability of capillaries

Question 46

three types of capillaries

Answer 46

1. continuous capillary 2. fenestrated capillary 3. sinusoid

Question 47

continuous capillary

Answer 47

most common least permeable regulates and transcellular exchange

Question 48

fenstrates capillary

Question 49

fenstrates capillary

Answer 49

holes and gaps within endothelial cells junctions in between more leaky

Question 50

sinusoid

Answer 50

very large gaps/holes high rate of exchange = important in liver

Question 51

where are fenstrated capillary found?

Answer 51

intestine and kidney

Question 52

where are sinusoidal capillary found?

Answer 52

bone marrow and liver

Question 53

venous return

Answer 53

1. smooth muscle contraction- movement 2. muscle pumping surrounding skeletal muscle 3. valves- prevent unidirectional flow

Question 54

lymphatic capillary

Answer 54

blind ended collection no red blood cells

Question 55

lymphatic vessels

Answer 55

go to lymnodes then return to the venus system

Question 56

three major tunics/ layers of blood vessels

Answer 56

intima, media, adventitia