cardiovascular

Question 1

functions of the cardiovascular system

Answer 1

Transport substances like oxygen and nutrients to cells
Transport metabolic wastes from cells and organs
Transport hormones, WBC, clotting proteins
Homeostasis (thermoregulation) (pH, hormones etc)

Question 2

explain the flow of blood through the heart

Answer 2

Deoxygenated blood enters the right atrium through the vena cava, then it enters the pulmonary valve which then transports blood to the lungs.
At the lungs the oxygen undergoes gas exchange, it becomes oxygen rich.
The blood then travels around the body in veins, it then return to the left atrium, then into the left ventricle, then it travels out into the pulmonary veins, around the bodies.

Question 3

what is ECG

Answer 3

Electrocardiogram (ECG) a visual display of the electricity polarisation in the heart.

Question 4

describe the two hear sounds and what happens

Answer 4

First heart sounds (soft dubb as the AV valves close simultaneously)
Second heart sounds (louder dubb as the semilunar valves close simultaneously)

Question 5

describe the artery and their function

Answer 5

tubular structure, very thick arterial walls that carry the blood away from the heart. They have thick smooth muscles, then endothelial layers internally. There are then arterioles, they are smaller arteries that lead into the capillaries that aid in blood regulation levels.

Question 6

describe the vein and their function

Answer 6

carries deoxygenated back to the heart. They have thinner walls than arteries, not the vena cava is the largest vein and venules are smaller branches of arteries that connect to the capillaries. Note that they have venous valves, they are surrounded by skeletal muscle that contract to move the blood, the valves close if the blood moves in the wrong direction.

Question 7

describe the capillary and their function

Answer 7

exchange the blood oxygenated and deoxygenated, they are a network that connect to both veins and arteries, they are the site of exchange plasma and interstitial fluid.) they hold no muscular walls, they do have pore that allow for passive movement.

Question 8

what is cardiac output

Answer 8

Cardiac output is the amount of blood the heart pushes outward in a minute (stroke volume x heart rate)

Question 9

define heart rate

Answer 9

Heart rate is the number of beats per minute.

Question 10

define stroke volume

Answer 10

Stroke volume - the amount of blood that the heart outputs in a single beat. (end diastolic volume - end systolic volume)

Question 11

define venous return

Answer 11

Venous return is determined by the muscles contraction (increased by exercise)
the blood theat return to the heart

Question 12

Sympathetic innervation

Answer 12

increase contractility of the ventricle, increasing the stroke volume.

Question 13

what are the two impacts on stroke volume

Answer 13

venous return
sympathetic innervation

Question 14

what is the symathetic nervous sytem influence on heart rate

Answer 14

increase the heart rate by stimulating the SA node by pumping adrenaline which controls the B - adrenoceptors, these receptors speed the SA node, increasing heart rate. this is largley due to the thoracic and cervical nerves (accelatory centre)

Question 15

what is the parasympathetic system influence on heart rate

Answer 15

decrease the heart rate. The heart muscle cells have ion channels. When potassium is pumped in the heart slows as the SA node reacts. This is largley connected to the vagus nerve

Question 16

define blood pressure

Answer 16

force exerted on the walls measured in mmHg (millimetres of mercury) arteries have the highest and vein the lowest. Blood pressure is pulsatile, it changes depending on the phase of the heart cycle

Question 17

Define diastolic pressure

Answer 17

where is minimum pressure is (80)

Question 18

define systolic pressure

Answer 18

where the maxim pressure is (120)

Question 19

define pulse pressure

Answer 19

the difference between the diastolic and systolic pressure

Question 20

define mean arteial pressure

Answer 20

average blood pressure over several heart beats.

Question 21

define baroreceptor reflex

Answer 21

Baroreceptors are pressure sensory receptors that respond by either stretching the arteries or contracting. They are located in the aortic arch and the carotid sinus.

Question 22

what are the two mechanism of autoregulaton of blood flow

Answer 22

metabolic and myogenic

Question 23

deifne myogenic mechanisim of blood flow

Answer 23

contraction of the vascular smooth muscle decreases the friction that the blood undergoes and increases the blood flow.

Question 24

define metabloic mechanisim of blood flow

Answer 24

supply and demand, when needed to the blood vessels will increase blood flow of nutrients towards a tissue. This is situational (consider injury).

Question 25

what are the regulatory pressure of mean arterial pressure (MAP)

Answer 25

There are short term regulation (heart and blood vessels, chemical control) or long term regulation (kidneys, hormonal)

Question 26

what are they two factors that influence the MAP

Answer 26

cardiac output
Total peripheral resistance.
- Diameter of the vessels
- Length of the vessels
- Smoothness of the vessels
- Viscosity of the blood

Question 27

what is the name for the ‘heart strings’ and the mucles that move them

Answer 27

chordae tendeae and the palpitory mucles

Question 28

what is the name of the valve that connects the right atrium and right ventricle, and why is it called that

Answer 28

tricuspid
tricuspid means three, as there are three segments tin the valve.

Question 29

what is the name of the valve that connects the left atrium and left ventricle, and why is it called that

Answer 29

bicuspid (matrial)
bicuspid mean 2 as the vavle has two function segments

Question 30

what is the pace maker of the heart

Answer 30

Sinoatrial node

Question 31

what is the second electricle nod of the heart and what does it connect to that aids in eletrical conduction

Answer 31

Atrioventritular node, which is connected to bundle branchs that are around the ventricles.

Question 32

what are the four phases of the cardiac cycle

Answer 32

1. ventricular filling
2. isovolumetric ventricular contraction
3. ventriculare ejection
4. isovolumetric ventricular relaxation