the heart

Question 1

overview

Answer 1

• The right side receives oxygen-poor blood from the body and tissues and then pumps it to the lungs to pick up oxygen and dispel carbon dioxide
• its left side receives oxygenated blood returning from the lungs and pumps this blood throughout the body to supply oxygen and nutrients to the body tissues

Question 2

strongest part of the heart

Answer 2

-left ventricle

Question 3

the heart simplified

Answer 3

• cone shaped
• 4 chambers - two atria and two ventricles
• double pump - the ventricles

Question 4

systemic circulation

Answer 4

-blood vessels that transport blood to and from all the body tissues

Question 5

pulmonary circulation

Answer 5

blood vessels that carry blood to and from the lungs

-much less pressure then systemic circulation

Question 6

base

Answer 6

-top of heart

Question 7

apex

Answer 7

-tip of heart

Question 8

location of heart

Answer 8

In mediastinum -> behind sternum and pointing left, lying on the diaphragm

Question 9

weight of heart

Answer 9

It weighs 250-350 gm (about 1 pound)

Question 10

pericardium layers

Answer 10

• Three layered:
• 1. Fibrous pericardium
• 2. Serous pericardium of layers (2) & (3)
     - Parietal layer of serous pericardium
     - Visceral layer of serous pericardium = epicardium: on heart and is part of its wall (Between the layers is pericardial cavity)

Question 11

myocardium

Answer 11

-muscle of the heart

Question 12

epicardium

Answer 12

-visceral layer of serous pericardium

Question 13

endocardium

Answer 13

-layer lining the chambers

Question 14

layers from out to in

Answer 14

• epicardium
• myocardium
• endocardium

Question 15

interatrial septum

Answer 15

-divides the left and right ventricles

Question 16

atrium

Answer 16

• prime the ventricles

- makes sure ventricles are able to enough contract blood

Question 17

interventricular septum

Answer 17

-separate left and right ventricles

Question 18

tricuspid valve

Answer 18

-from right atrium to right ventricle

Question 19

pulmonary or pulmonic valve

Answer 19

-right ventricle to pulmonary trunk (R and L branch)

Question 20

semilunar valves

Answer 20

-pulmonic and aortic valves

Question 21

mitral valve (bicuspid)

Answer 21

-left atrium to left ventricle

Question 22

aortic valve

Answer 22

-left ventricle to aorta

Question 23

flow

Answer 23

-Body to right heart to lungs to left heart to body
-Body, then via vena cavas and coronary sinus to RA, to RV, then to
lungs via pulmonary arteries, then to LA via pulmonary veins, to LV, then to body via aorta
-From body via SVC, IVC & coronary sinus to RA; then to RV through tricuspid valve; to lungs through pulmonic valve and via pulmonary arteries; to LA via pulmonary veins; to LV through mitral valve; to body via aortic valve then aorta

Question 24

relative thickness of muscular walls

Answer 24

• LV thicker than RV because it forces blood out against more resistance;
• systemic circulation is much longer than the pulmonary circulation
• Atria are thin because ventricular filling is done by gravity, requiring little atrial effort

Question 25

heartbeat

Answer 25

a single sequence of atrial contraction followed by ventricular contraction

Question 26

systole

Answer 26

contraction

Question 27

diastole

Answer 27

filling

Question 28

normal heart rate

Answer 28

60-100

Question 29

tachycardia

Answer 29

greater than 100

Question 30

bradycardia

Answer 30

-slower than 60

Question 31

S1 : Heart sound

Answer 31

-S1 is the closing of AV (Mitral and Tricuspid) valves at the start of ventricular systole

Question 32

S2 : Heart sound

Answer 32

- S2 is the closing of the semilunar (Aortic and Pulmonic) valves at the end of ventricular systole - Separation easy to hear on inspiration therefore S2 referred to as A2 and P2

Question 33

murmurs

Answer 33

- the sound of flow - Can be normal - Can be abnormal

Question 34

places to auscultate the heart

Answer 34

-Routine places are at right and left sternal border and at apex

Question 35

electrical conduction signal

Answer 35

- specialized cardiac muscle cells that carry impulses throughout the heart musculature, signaling the chambers to contract in the proper sequence - can create its own signal - originates in the SA node - AV node delays enough for the atria to contract before the ventricles - bundle of his - right and left bundle branches - right and left ventricles - purkinje fibers

Question 36

SA node

Answer 36

- sinoatrial - in wall of right atrium - sets basic rate (60-100) - is the normal pacemaker - impulse from SA to atria - impulse also to AV node via internodal pathway

Question 37

atria

Answer 37

-contract top down

Question 38

ventricle

Answer 38

-contract bottom up

Question 39

AV node

Answer 39

In interatrial septum | -40-60

Question 40

AV bundle (bundle of his)

Answer 40

- Into interventricular septum | - Divides R and L bundle branches become subendocardial branches (“Purkinje fibers”)

Question 41

contractions being at the

Answer 41

apex

Question 42

autonomic innervation

Answer 42

- Sympathetic -> Increases rate and force of contractions | - Parasympathetic (branches of Vagus nerve) -> Slows the heart rate

Question 43

AV node

Answer 43

40-60