intro to cardiovascular system

Question 1

function of the cardiovascular system

Answer 1

transfer of oxygen and carbon dioxide
transfer of nutrients
transfer of hormones
transfer of heat

Question 2

why is the cardiovascular system very reliable

Answer 2

this is because the pump can vary output
the vessels can redirect blood
vessels can store blood

Question 3

arrangement of the pumps

Answer 3

arranged in series in order for the output to be equal to the input

Question 4

arrangement of the vascular beds

Answer 4

arranged in parallel so that all tissues can get oxygenated blood and this allows redirection of blood.

Question 5

what is the flow of blood

Answer 5

blood flow is the pressure gradient /resistance

Question 6

relationship between flow and pressure

Answer 6

flow is directly proportional to pressure and inversely proportional to resistance

Question 7

function of arterioles

Answer 7

they are taps that control resistance to each of the vascular bed

Question 8

regional redirection of blood flow

Answer 8

occurs in the arteries

Question 9

function of veins

Answer 9

storage of blood ; there is blood pooling in the veins 2/3 of the blood

Question 10

control of fractional distribution of blood

Answer 10

veins

Question 11

control of regional distribution if blood

Answer 11

arteries

Question 12

structure of an artery

Answer 12

muscular
wide lumen
strong thick and non elastic wall
low resistance conduit

Question 13

Septum

Answer 13

Separates the left and the right side

Question 14

Mitral valve

Answer 14

Located between the atrium and the ventricle of the left side

Question 15

Tricuspid valve

Answer 15

Located between the atrium and the ventricle of the right hand side

Question 16

Papillary muscle

Answer 16

Holds the atrioventricular valves and prevents regurgitation

Question 17

Aortic valve

Answer 17

Valve at the bottom of the aorta

Question 18

Pulmonary valve

Answer 18

Valve at the bottom of the pulmonary artery

Question 19

Pulmonary trunk

Answer 19

Pulmonary artery

Question 20

What causes contraction in the myocytes of the heart

Answer 20

Influx of calcium ions

Question 21

Is there tetanus in cardiac muscle cells

Answer 21

No ;this is to enable the cells to relax so there is filling up of the heart

Question 22

Intercalated discs

Answer 22

Electrically connected via the gap junctions
Physically connected via desmosomes

Question 23

Action potential in a cardiac muscle

Answer 23

Longer than action potential in normal muscle cells

Question 24

Pacemaker cells

Answer 24

They have unstable membrane potential
This means they do not need a stimulus to generate the action potential

Question 25

Action potential of a non pacemaker

Answer 25

Entry of sodium ions into the cell upto a certain positive membrane potential Permeability of sodium ions reduces Permeability of potassium ions decreases while the permeability of calcium ions increases This is at the plateau phase . The permeability of potassium ions increases while calcium ions decreases

Question 26

Resting membrane potential of the non pacemaker action potential

Answer 26

There is permeability of potassium ions

Question 27

Pacemaker pre potential

Answer 27

Very unstable Andean it is controlled by the funny ion channels which enables the cells to reach the threshold for shooting of an action potential allow the sodium ions and a decrease in the potassium levels as well as the late increase in calcium ions

Question 28

how is the action potential of the pacemaker cells generated

Answer 28

The funny ion channels close ; tiny calcium ion channels at the start ;at the end there are more L -type calcium ions that open

Question 29

Action potential of the pacemaker cells

Answer 29

Increas in calcium ions to the most. Positive threshold ;before the calcium ions close and there is increased in the permeability of potassium ions until it reaches negative

Question 30

Sinoatrial node

Answer 30

Pacemaker that releases the signals

Question 31

Atrioventricular node

Answer 31

Delaying the spread of the electrical signals which is to enable the atrium to contract before spreading in wave

Question 32

Bundle his and purkinje fibres

Answer 32

There is rapid conduction of electrical signals

Question 33

Atrial excitation

Answer 33

Sinoatrial node releases. The signal waves to the AVN. ,the atrium contracts

Question 34

Atrial fibrillation

Answer 34

There is loss of the p wave

Question 35

Ventricular fibrillation

Answer 35

There is loss of the qrs complex

Question 36

Systolic pressure

Answer 36

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