EAC Cardio-Vascular CV System

Question 1

functions of the CV system

Answer 1

To transport essential foodstuffs, oxygen, water, enzymes and hormones to the cells of the body

To remove waste products that are produced by cell metabolism to the excretory organs

Question 2

components of the CV system

Answer 2

Heart

Blood vessels

Blood

Question 3

CV circulation divisions

Answer 3

Systemic: passage of blood around the body

Pulmonary: passage of blood through the lungs

Coronary: supply of blood to/from the heart muscle

Hepatic Portal: supply of blood to/from the liver (is a branch of systemic)

Question 4

describe:

structure of the heart

Answer 4

The heart is a hollow cone shaped muscular organ

In an average adult it is the size of the owners clenched fist

Question 5

state the location of the heart

Answer 5

The heart is situated within the thoracic cavity.

It lies in the mediastinum behind the sternum, in front of the spine, between the lungs and above the diaphragm.

The base lies behind the sternum and extends to the 2nd rib

The apex is approx. 9cm to the left of the midline, in the mid-clavicular line at the 5th intercostal space

Question 6

describe the structure of the heart

Answer 6

The walls of the heart are composed of three main layers:

Pericardium (outer)

Myocardium (mid)

Endocardium (inner)

Question 7

Pericardium consists of

Answer 7

Fibrous pericardium

Parietal pericardium

Pericardial space fill with Pericardial fluid

Visceral pericardium

Question 8

function of:
Pericardium

Answer 8

The pericardium prevents over distension of the heart and the pericardial serous fluid allows for smooth frictionless movement when the heart beats.

Question 9

function of:
Myocardium

Answer 9

Muscle of the heart, thickest around the left ventricle. has automaticity which means it doesn’t require outside stimulus to produce muscle contraction.

Question 10

function of:
Endocardium

Answer 10

A thin smooth squamous epithelial membrane to ensure smooth flow of blood through the heart.

It lines the chambers of the heart and the valves.

Its continuous with the lining of blood vessels.

Helps to prevent local blood clotting.

Question 11

flow of blood through the heart (right side)

Answer 11

Inferior and superior vena cava

Right atrium

Tricuspid valve

Chordae tendineae

Papillary muscle

Right ventricle

Pulmonary valve

Pulmonary trunk

Left and right pulmonary artery

Lungs

Question 12

flow of blood through the heart (left side)

Answer 12

Lungs

left and right pulmonary vein

Left atrium

Bicuspid valve

Chordae tendineae

Papillary muscle

Left ventricle

Aortic valve

Arch of aorta

Aorta

Rest of body

Question 13

Describe:

Coronary circulation

Answer 13

Coronary circulation is the circulation of blood in the blood vessels of the heart muscle.

Right coronary artery

Left coronary artery
-which the Circumflex artery branches off

Question 14

Describe:

Cardiac Cycle

Answer 14

Atrial systole - contraction of atria - 0.1 sec

Ventricular systole - contraction of ventricles - 0.3 sec

Cardiac diastole - relaxation phase - 0.4 sec

Question 15

Describe:

Electrical Conduction System of the heart

Answer 15

specialised cardiac cells that produce electrical impulses to cause the heart to contract

Sino-Atrial node SA
Atrio-Ventricular node AV
Left and Right bundle branches
Purkinje Fibres

Question 16

Explain:

Nervous Control of the heart

Answer 16

Cardiovascular centre located within the medulla oblongata

sympathetic/Parasympathetic nervous control regulates heart rate

Question 17

Average heart rates

Answer 17

60-100 = adult

100-120 = 6-12yrs

120-140 = 1-5yrs

140-160 = 1mnth-1yr

Question 18

factors that increase heart rate

Answer 18

position

age/sex

exercise

emotion

cardiac/medical conditions

shock and blood loss

drugs/chemicals

Question 19

factors that decrease heart rate

Answer 19

age

general health

vagal stimulation

cardiac conditions

medical conditions

drugs

Question 20

define:

Bradycardia

Answer 20

Slow heart rate of less then 60bpm

Question 21

define:

Tachycardia

Answer 21

Rapid heart rate of more then 100bpm

Question 22

name the 5 types of blood vessel

Answer 22

Arteries
Arterioles
Capillaries
Venules
Veins

Question 23

describe:

structure of blood vessels

Answer 23

Three layers:

outer fibrous sheath = Tunica Adventitia

middle layer of muscle and elastic fibre = Tunica Media

smooth inner lining of endothelium = Tunica Intima

Question 24

describe the structure and function of:

Arteries

Answer 24

carry blood away from the heart

they have a strong outer (tunica adventitia) coat and thick muscle layer (tunica media)

Question 25

describe the structure and function of:

Arterioles

Answer 25

these are smaller arteries

dilate or contract to control the blood flow into the capillary bed

Question 26

describe the structure and function of:

Capillaries

Answer 26

Have very thin walls. A single layer of cells.

they allow for the interchange of gases and transfer of nutrients and waste products

Question 27

describe the structure and function of:

Venules

Answer 27

these are smaller veins

Venules dilate or contract to control the blood flow out of the capillary bed

Question 28

describe the structure and function of:

Veins

Answer 28

Veins carry blood back to the heart

they have thinner walls then arteries

some veins have valves to prevent back-flow of blood

Question 29

Define:

Venous Return

Answer 29

The amount of blood returning to the heart. The force of contraction of the left ventricle is not sufficient on its own to ensure effective return of the blood to the heart via the veins.

Question 30

Four factors that assist in venous return

Answer 30

Position of the body

Muscular contraction

Respiratory movements

Suction of the heart

Question 31

Define:

Pulse

Answer 31

a rhythmical pulsation of the arteries as blood is propelled through them, typically as felt in the wrists (radial) or neck (carotid)

Question 32

what information can be obtained from a pulse

Answer 32

Pulse rate

A rough blood pressure

circulatory issues i.e. no pedal pulse in fractured leg/ankle/foot

Question 33

Define:

Blood Pressure

Answer 33

The force or pressure exerted on the walls of the blood vessels by the blood.

This pressure is higher in the arteries than in the veins.

Question 34

Define:

Pulse Pressure

Answer 34

the difference between systolic and diastolic pressures

Question 35

the component parts of blood

Answer 35

Liquid part:
Plasma 55%

Solid part:
Erythrocytes
Leucocytes
Thrombocytes

Question 36

the 7 main functions of blood

Answer 36

carry o2 and co2

carry nutrients and water

carry waste products

protect body from infection

sealing of wounds

distribute the secretions of glands

distributes heat

Question 37

State the normal range of blood volumes

Answer 37

70ml per kg of body weight

Question 38

describe the blood clotting process

Answer 38

Damage platelets release the enzyme Thrombokinase around site of injury

Thrombokinase, calcium salts and prothrombokinase (plasma protein) all combine to form an activating enzyme called thrombin

Thrombin converts fibrinogen (plasma protein) into fibrin threads

Fibrin threads entrap blood cells and bind them to the tissues to form a clot

Question 39

position and function of the spleen

Answer 39

The spleen is an organ in the upper far left part of the abdomen, to the left of the stomach.

It acts as a filter for blood as part of the immune system. Old red blood cells are recycled in the spleen, and platelets and white blood cells are stored there.