CARDIO- overview of cardiovascular system

Question 1

what is passive diffusion

Answer 1

movement of molecules down a concentration gradient

Question 2

what is convective transport

Answer 2

movement of solutes / fluids down a pressure gradient

Question 3

what are the features of passive diffusion

Answer 3

random
undirected
thermal movement of molecules
occurs via equation - time is proportional to distance squared

passive diffusion is good over short distances but not good for long distances

Question 4

why is a cardiovascular system required to maintain body function

Answer 4

establishment of convective transport for perfusion to organs / peripherals

Question 5

what are the roles of the heart and blood vessels in the cardiovascular system

Answer 5

transport oxygen and substrates to cells
transport carbon dioxide and metabolites for excretion
distribution of hormones
transport of defence mechanisms
thermoregulation

Question 6

outline the electrical conduction of the heart

Answer 6

SA node
atrium
AV node
bundle branches 
purkinje fibres
ventricles

Question 7

what is the function of elastic vessels

Answer 7

large arteries
accommodate stroke volume
convert intermittent ejection onto continuous flow

Question 8

what is the function of resistance vessels

Answer 8

resistance vessels - arterioles - control arterial BP - control local blood flow

Question 9

what is the function of capacitance vessels

Answer 9

venules, veins

control filling pressure - reservoir of blood

Question 10

what is the function of exchange vessels

Answer 10

capillaries

nutrient delivery to the cells

tissue, water and lymph formation

removal of metabolic waste

Question 11

define HR

Answer 11

number of heart beats per min

Question 12

define stroke volume

Answer 12

volume of blood ejected from the heart per beat

Question 13

define total peripheral resistance

Answer 13

resistance of blood vessels to blood flow

Question 14

what is cardiac output

Answer 14

hr x sv

Question 15

what is blood flow

Answer 15

arterial BP / TPR

Question 16

what controls cardiac output

Answer 16

filling pressure - hypovolemia

sympathetic / parasympathetic autonomic nerves - excercise

chemical factors - adrenaline

afterload - hypertension

Question 17

describe the vessel circulation of blood

Answer 17

arteries 
arterioles
capillaries
diffusion
venules
veins
vena cava

Question 18

explain pressure differences that maintain blood flow

Answer 18

oscillating pressure in aorta

arterioles pressure drops

pressure drops in capillaries

pressure maintains low through venules and veins

Question 19

outline the velocity of blood flow through the circulation

Answer 19

remains high in the aorta
drops in capillaries - aids exchange
out of capillaries and into venules - increases velocity

Question 20

where is most of the blood circulation at any one time

Answer 20

capillaries

Question 21

what is the equation for calculating blood velocity

Answer 21

blood flow / cross sectional area

Question 22

outline the blood flow and pressure relationship

Answer 22

development of appropriate blood pressure is essential for maintaining blood flow and oxygen transport to tissues /organs

Question 23

what is the blood pressure of systemic circulation

Answer 23

120 / 80

Question 24

what is the blood pressure in pulmonary circulation

Answer 24

25 / 15

Question 25

hat affects blood pressure

Answer 25

CO and TPR

Question 26

what effect will a decrease in CO have

Answer 26

decrease in blood volume - reduce BP and produce poor blood flow to tissues

Question 27

what effect will an increase in TPR have

Answer 27

excessive arteriole constriction will switch off blood flow to tissues associated with an increase in BP upstream on constriction - potential cause and consequence of hypertension

Question 28

what is meant by the saying the cardiovascular system in a dual circulation

Answer 28

in parallel - cardiac output is split up - safeguards oxygen supply - most of the organs are supplied this way therefore if there is an occlusion in say the lower part of the body the upper part is unaffected in series - some organs use 'used' blood - liver and kidney - can be an issue for these organs if the CVS is compromised

Question 29

true / false - the cardiovascular system is a closed system

Answer 29

true