cardiovascular

Question 1

what does diastole mean?

Answer 1

pressure decrease in ventricles where blood flows into the ventricle

Question 2

what does systole mean?

Answer 2

pressure increase in ventricle where AV valves close and semilunar valves open.

Question 3

what is the purpose of the valves in the heart?

Answer 3

blood only flows in one way

Question 4

what are the principles of pressure and flow?

Answer 4

pressure (impels fluid to move), and resistance (opposes the flow)

Question 5

what are the heart sounds?

Answer 5

S1 - AV valves opening
S2 - SL valves opening

Question 6

what are the properties of cardiac conduction?

Answer 6

automaticity (spontaneous depolarization to a threshold).
Rhythmicity (regular generation of action potentials by heart conduction system)

Question 7

how do electrical signals travel throughout the heart?

Answer 7

through gap junctions

Question 8

where do electrical impulses begin?

Answer 8

the Sinoatrial node through pace maker cells

Question 9

what is the P wave?

Answer 9

atria begin depolarizing

Question 10

what is the QRS complex?

Answer 10

ventricle depolarization begins at apex then ventricular depolarization completes

Question 11

what is the T wave?

Answer 11

ventricular repolarization beginning at apex and progresses superiorly.

Question 12

what is the stroke volume?

Answer 12

volume of blood pumped with each beat

Question 13

what is a proprioceptor?

Answer 13

receive information from muscles and joints

Question 14

what is a baroreceptor

Answer 14

detects pressure in aorta and internal corotid arteries

Question 15

what is a chemoreceptor?

Answer 15

detects the blood pH, CO2 and O2 levels

Question 16

what is atherosclerosis?

Answer 16

fat build up in arteries

Question 17

what is pulse pressure?

Answer 17

this is the difference between systolic and diastolic pressures, measures stress on small arteries generated by heart

Question 18

what are the factors affecting resistance?

Answer 18

viscosity
vessel length
vessel radius

Question 19

what is laminar flow?

Answer 19

flows in layers where it is faster in the centre

Question 20

what is vasoconstriction?

Answer 20

smooth muscles contract the vessels

Question 21

what is vasodilation?

Answer 21

smooth muscles relax increasing diameter

Question 22

what are vasoreflexes?

Answer 22

quick and powerful ways of regulating blood pressure and flow

Question 23

what is autoregulation?

Answer 23

ability of tissues to regulate own blood supply

Question 24

what are vasoactive chemicals

Answer 24

substances secreted by platelets, endothelial cells and perivascular tissue

Question 25

what is the vasomotor centre of the medulla?

Answer 25

this controls the sympathetic reactions of the blood vessels in the body

Question 26

what is a chemoreflex?

Answer 26

autonomic response to alterations in blood chemistry

Question 27

which hormones control blood pressure?

Answer 27

angiotensin II, Atrial natriuretic peptide, ADH, epinephrin and norepinephrine

Question 28

what is capillary exchange

Answer 28

two way movement of fluid across capillary walls

Question 29

what mechanisms are involved in capillary exchange?

Answer 29

diffusion, transcytosis, filtration, reabsorption.

Question 30

what are the opposing forces of capillary exchange?

Answer 30

blood hydrostatic pressure, colloid osmotic pressure

Question 31

what is venous return?

Answer 31

flow of blood back to the heart

Question 32

what is venous return affected by?

Answer 32

pressure gradient, gravity, skeletal muscles, thoracic pump.