Chapter 12: The Heart

Question 1

What is the approximate weight of the heart

Answer 1

less than one pound

Question 2

where is the heart located

Answer 2

the mediastinum

Question 3

What are the membranous layers of the heart

Answer 3

The outer fibrous pericardium (pericardial sac), parietal pericardium, visceral pericardium (epipericardium), pericardial cavity

Question 4

What are the layers of the heart wall

Answer 4

epicardium, myocardium, endocardium

Question 5

what makes the lub sound

Answer 5

closing of the av valves

Question 6

what makes the dub sound

Answer 6

closing of semilunar valves

Question 7

what is the pulmonary circuit

Answer 7

superior and inferior vena cava, right atrium, tricuspid valve, right ventricle, pulmonary semilunar valve, pulmonary trunk, lungs

Question 8

What is the systemic circuit

Answer 8

lungs, pulmonary veins, left atrium, bicuspid valve, left ventricle, aortic semilunar valve, aorta, body tissues

Question 9

what is the coronary circuit

Answer 9

lungs, pulmonary veins, left atrium, bicuspid valve, left ventricle, aortic semilunar valve, aorta, heart tissue, coronary sinus, cardiac veins

Question 10

define atherosclerotic plaque

Answer 10

fatty deposits in the lining of coronary arteries

Question 11

define angina pectoris

Answer 11

chest pain from exertion that subsides when the activity is stopped

Question 12

define myocardial infarction (MI)

Answer 12

when there is a 100% blockage in a coronary artery

Question 13

define angioplasty

Answer 13

procedure using a catheter with a small balloon that is inflated at sites of atherosclerosis to widen the lumen

Question 14

define coronary bypass

Answer 14

procedure where a vessel is grafted onto the heart to go around a partially blocked region

Question 15

what ions prolong the peak of the action potential in cardiac muscle

Answer 15

calcium ions

Question 16

what does a myogram do

Answer 16

measures the tension produced by muscle

Question 17

what is the conduction system in order

Answer 17

sinoatrial node, atrioventricular node, atrioventricular bundle, R+L bundle, purkinje fiber

Question 18

what does the p wave represent on an ECG

Answer 18

atrial depolarization

Question 19

what is the QRS complex representing

Answer 19

ventricular depolarization

Question 20

what does the t wave represent

Answer 20

ventricular repolarization

Question 21

define arrhythmia

Answer 21

any abnormality in the electrical activity of the heart; many types; can be detected with electrocardiograms

Question 22

define tachycardia

Answer 22

heart rate greater than 100 bpm

Question 23

define bradycardia

Answer 23

heart rate less than 60 bpm

Question 24

define fibrillation

Answer 24

out of phase electrical activity, heart is useless as a pump

Question 25

What are the steps in the cardiac cycle

Answer 25

1. Heart in diastole - av valves open and ventricles fill 2. Atrial systole 3. Begin ventricular systole - av valves close 4. Mid to late Ventricular systole - ventricular psi is greater than artery psi 5. Being ventricular diastole - ventricular psi less than psi in artery; semilunar valves close

Question 26

How do you determine Cardiac Output

Answer 26

multiple bpm by the rest of the stroke volume

Question 27

what is cardiac output

Answer 27

volume of blood pumped by the heart in one minute

Question 28

what is stroke volume

Answer 28

volume of blood pumped per ventricle in one beat

Question 29

what is EDV (preload)

Answer 29

volume of blood in the ventricle at the end of diastole

Question 30

What is ESV

Answer 30

volume of blood in the ventricle at the end of systole

Question 31

what is preload

Answer 31

degree to which ventricles are stretched at EDV

Question 32

what is afterload

Answer 32

pressure against which the ventricles must pump

Question 33

stretching of the atria stimulates this reflex

Answer 33

atrial/ bainbridge reflex

Question 34

when there is a ______ in venous, there is a ________ in heart rate and force of contraction

Answer 34

increase; increase

Question 35

in venous return and filling time tachycardia has a ______ in filling time

Answer 35

decrease

Question 36

in venous return and filling time in bradycardia has a ______ in filling time

Answer 36

increase

Question 37

stretching the ventricles stimulates this reflex

Answer 37

starlings law of the heart (more in=more out)

Question 38

The Cardioregulatory Center is in which part of the brain

Answer 38

medulla oblongata

Question 39

The parasympathetic NS is associated with which nerves

Answer 39

vagus nerves

Question 40

The sympathetic NS is associated with which nerves

Answer 40

cardiac nerves

Question 41

What is the neurotransmitter in the parasympathetic NS

Answer 41

acetylcholine

Question 42

what is the role of acetylcholine in the parasympathetic NS

Answer 42

decrease the Heart Rate and Stroke Volume

Question 43

what is the neurotransmitter in the sympathetic NS

Answer 43

norepinephrine

Question 44

what is the role of norepinephrine in the sympathetic NS

Answer 44

increase Heart Rate and Stroke Volume

Question 45

What does the suprarenal (adrenal) medulla secrete

Answer 45

epinephrine and norepinephrine

Question 46

What is the baroreceptor reflexes

Answer 46

response to increased BP

Question 47

when CO is increased, BP is ______

Answer 47

increased

Question 48

when CO is decreased, BP is ________

Answer 48

decreased

Question 49

What is the Baroreceptor Reflex stimulus

Answer 49

increased BP

Question 50

what are the Baroreceptor Reflex receptors

Answer 50

baroreceptors pertaining to the carotid sinus and aortic arch

Question 51

what are the Baroreceptor Reflex sensory nerves

Answer 51

the glossopharyngeal and the vagus nerve

Question 52

what are the Baroreceptor Reflex effectors

Answer 52

cardioregulatory center of medulla oblongata (PNS, SNS)

Question 53

what are the Baroreceptor Reflex response

Answer 53

decreased blood pressure

Question 54

What is the role of the Renin-Angiotensin-Aldosterone Mechanism

Answer 54

Regulates blood volume + BP

Question 55

What is renin?

Answer 55

an enzyme produced by kidneys

Question 56

what does renin do?

Answer 56

convert angiotensinogen into angiotensin 1

Question 57

What is aldosterone

Answer 57

a hormone produced by the adrenal cortex

Question 58

what does aldosterone do?

Answer 58

Targets kidneys to reabsorb Na+ and secrete K+

Question 59

What is ADH

Answer 59

a hormone produced by the hypothalamus, and stored in the posterior pituitary

Question 60

What does ADH do

Answer 60

targets the kidneys to reabsorb H2O and increase blood volume + blood pressure