A&p Ii Test #2

Front 1

Pulmonary Circuit

Back 1

The flow of blood from the heart through the lungs back to the heart
Picks up oxygen and releases carbon dioxide in the lungs

Front 2

System Circulation:

Back 2

The flow of blood from the heart through the body back to the heart
Delivers oxygen and picks up carbon dioxide in the body’s tissues

Front 3

Location, size and shape of the heart

Back 3

Location
Anterior to the vertebral column, posterior to the sternum
Left of the midline
Deep to the second to fifth intercostal spaces
Superior surface of diaphragm
Shaped like a blunt cone, with an apex and a base
Approximately the size of your fist

Front 4

Pericardial Sac that encloses the heart:

Back 4

a double-walled sac around the heart composed of
A superficial fibrous pericardium
A deep two-layer serous pericardium

Front 5

parietal layer

Back 5

lines the internal surface of the fibrous pericardium

Front 6

visceral layer

Back 6

lines the surface of the heart

Front 7

pericardial cavity

Back 7

Parietal and Visceral layer are separated by the fluid-filled (pericardial fluid)

Front 8

Three Layers of the Heart Wall:

Back 8

Epicardium
Myocardium
Endocardium

Front 9

Epicardium

Back 9

Visceral layer of the serous pericardium (visceral pericardium)
Provides protection against the friction of rubbing organs

Front 10

Myocardium

Back 10

Cardiac muscle layer forming the bulk of the heart
Responsible for contraction

Front 11

Endocardium

Back 11

Endothelial layer over crisscrossing, interlacing layer of connective tissue
Inner endocardium reduces the friction resulting from the passage of blood through the heart

Front 12

4 chambers of the heart:

Back 12

The two ventricles (right and left) are muscular chambers that propel the blood out of the heart (the right ventricle to the lungs, and the left ventricle to all other organs).
The two atria (right and left) hold the blood returning to the heart, and at just the right moment empty into the right and left ventricles.

Front 13

Atrioventricular (AV) valves

Back 13

lie between the atria and the ventricles
AV valves prevent backflow into the atria when ventricles contract

Front 14

Chordae tendineae

Back 14

anchor AV valves to papillary muscles

Front 15

Tricuspid valve:

Back 15

separates the right atrium and ventricle

Front 16

Bicuspid valve:

Back 16

separates the left atrium and ventricle

Front 17

Semilunar valves do what?

Back 17

prevent backflow of blood into the ventricles

Front 18

Two types of semilunar valves:

Back 18

Aortic semilunar valve: lies between the left ventricle and the aorta
Pulmonary semilunar valve: lies between the right ventricle and pulmonary trunk

Front 19

Route of Blood Flow through the heart: Blood from the body....

Back 19

flows through the right atrium into the right ventricle and then to the lungs

Front 20

Route of Blood Flow from the lungs....

Back 20

Blood returns from the lungs to the left atrium, enters the left ventricle, and is pumped back to the body

Front 21

Coronary arteries

Back 21

branch off the aorta to supply the heart
Blood returns from the heart tissues to the right atrium through coronary sinus and cardiac veins

Front 22

Fibrous Skeleton of the Heart

Back 22

Consists of a plate of fibrous connective tissue
Forms fibrous rings around the AV and SL valves for support
Provides a point of attachment for heart muscle
Electrically insulates the atria from the ventricles

Front 23

Cardiac Muscle Cells

Back 23

Are branched and have a centrally located nucleus
Actin and myosin are organized to form sarcomeres (striated)
T tubules and sarcoplasmic reticulum are not as organized as in skeletal muscle
Normal contraction depends on extracellular Ca2+
Rely on aerobic respiration for ATP production
They have many mitochondria and are well supplied with blood vessels
Joined by intercalated disks
Allow action potentials to move from one cell to the next, thus cardiac muscle cells function as a unit

Front 24

Action Potentials
(electrical activity of the heart)

Back 24

After depolarization and partial repolarization, a plateau phase is reached, during which the membrane potential only slowly repolarizes
The opening and closing of voltage-gated ion channels produce the action potential

Front 25

depolarization

Back 25

The movement of Na+ through Na+ channels

Front 26

During depolarization

Back 26

K+ channels close and Ca2+ channels begin to open

Front 27

Early repolarization results from ...

Back 27

closure of the Na+ channels and the opening of some K+ channels

Front 28

The plateau exists because ...

Back 28

Ca2+ channels remain open

Front 29

The rapid phase of repolarization results from

Back 29

the closure of the Ca2+ channels and the opening of many K+ channels

Front 30

2 Refractory Periods :

Back 30

Absolute refractory period
Cardiac muscle cells are insensitive to further stimulation
Relative refractory period
Stronger than normal stimulation can produce an action potential

Front 31

Why do cardiac muscles relax before AP causes a contraction?

Back 31

Cardiac muscle has a prolonged depolarization and thus a prolonged absolute refractory period

Front 32

Some cardiac muscle cells are autorhythmic because ...

Back 32

spontaneous development of a prepotential
Prepotential: slowly developing local action potential

Front 33

sinoatrial (SA) node is...

Back 33

pacemaker of the heart
Collection of cardiac muscle cells capable of spontaneously generating action potentials

Front 34

Heart rate is determined by...

Back 34

duration of the prepotential

Front 35

Prepotential:

Back 35

slowly developing local action potential

Front 36

The sinoatrial (SA) node and the atrioventricular (AV) node are in

Back 36

The RIGHT atrium

Front 37

The AV node is connected to

Back 37

the bundle branches in the interventricular septum by the AV bundle

Front 38

Purkinje fibers:

Back 38

supply the ventricles and carry the impulse to the heart apex and ventricular walls

Front 39

What does the SA node initiate?

Back 39

Action potentials that spread across the atria and cause contraction

Front 40

Where do the Action potentials slow down?

Back 40

AV node. This allows atria to contract and blood to flow into the ventricles

Front 41

atrioventricular bundles

Back 41

pass the action potentials from atria to ventricles

Front 42

Where do the AV bundle splits into two pathways ?

Back 42

interventricular septum

Front 43

P wave

Back 43

corresponds to depolarization of the atria (SA node)

Front 44

QRS complex

Back 44

corresponds to ventricular depolarization

Front 45

T wave

Back 45

corresponds to ventricular repolarization

Front 46

Atrial repolarization record is masked by the...

Back 46

QRS complex

Front 47

ECGs can be used to diagnose

Back 47

heart abnormailities

Front 48

Atrial systole

Back 48

contraction of the atria

Front 49

Systole

Back 49

contraction of the ventricles

Front 50

Atrial diastole

Back 50

relaxation of the atria

Front 51

Diastole

Back 51

relaxation of the ventricles

Front 52

During systole ( 4 things happen)

Back 52

AV valves close
Pressure increases in the ventricles
Semilunar valves are forced to open
Blood flows into the aorta and pulmonary trunk

Front 53

At the beginning of diastole (2 things happen)

Back 53

Pressure in the ventricles decreases
Semilunar valves close to prevent backflow of blood from the aorta and pulmonary trunk into the ventricles

Front 54

When the pressure in the ventricles is lower than in the atria

Back 54

the AV valves open and blood flows from the atria into the ventricles

Front 55

During atrial systole

Back 55

the atria contract and complete the filling of the ventricles

Front 56

3 Events Occurring During Ventricular Systole

Back 56

1. Ventricular depolarization
2.The volume of blood in a ventricle just before it contracts is the end- diastolic volume
3.The volume of blood after contraction is the end- systolic volume

Front 57

Ventricular depolarization produces:

Back 57

the QRS complex
Initiates contraction of the ventricles, which increases ventricular pressure
The AV valves close
Semilunar valves open
Blood is ejected from the heart

Front 58

Aortic Pressure Curve

Back 58

Contraction of the ventricles forces blood into the aorta

Front 59

systolic pressure is

Back 59

Maximum pressure in the aorta

Front 60

diastolic pressure is

Back 60

Minimum pressure in the aorta

Front 61

Heart sounds (lub-dup) are associated with :

Back 61

First sound occurs as AV valves close and signifies beginning of systole (lub)
Second sound occurs when SL valves close at the beginning of ventricular diastole (dup)

Front 62

Mean arterial pressure is

Back 62

the average blood pressure in the aorta

Front 63

Cardiac output (CO) is

Back 63

product of heart rate (HR) and stroke volume (SV)
HR is the number of heart beats per minute
SV is the amount of blood pumped out by a ventricle with each beat

Front 64

Venous return is

Back 64

the amount of blood returning to the heart

Front 65

Starling’s law

Back 65

describes the relationship between preload and the stroke volume of the heart
An increased preload causes the cardiac muscle fibers to contract with a greater force and produce a greater stroke volume

Front 66

LaPlace Law

Back 66

Force=Diameter * Pressure (anurism)

Front 67

Pousilles law

Back 67

velocity of a liquid flowing through a capillary is directly proportional to the pressure of the liquid (viscosity as well included)

Front 68

Ischemia (caused by low CO)

Back 68

Inadequate blood flow that fails to meet the oxygen demands of tissues

Front 69

4 Factors that govern CO:

Back 69

1-preload (volume)
2-Afterload (BP)
3-Cardiac Contractility
4-Pulse rate