Bio1008 - The Human Heart

Front 1

Cardiac Cycle

Back 1

Refers to the events that occur during a complete heartbeat

Front 2

Systole

Back 2

Contraction of the heart muscle

Front 3

Diastole

Back 3

Relaxation of the heart muscle

Front 4

Events of the cardiac cycle

Back 4

1. Blood returns to the heart and flows into the atria

2. Atrial systole

3. Ventricular systole

4. Ventricular diastole

Front 5

What happens during atrial systole?

Back 5

The pressure within the atria increases, forcing the remaining 30% of blood that did not flow directly into the ventricles through the AV valves

Front 6

What happens during ventricular systole?

Back 6

1. Atrial diastole

2. Pressure within the ventricles and the atria increases

3. Semilunar valves open and blood goes into either the ascending aorta or pulmonary trunk

Front 7

Why does the pressure in the atria increase during ventricular systole?

Back 7

Blood is forced against the AV valves, which push into the atria slightly

Front 8

What prevents the cuspid valves from opening into the atria?

Back 8

The contractions of the papillary muscles put tension on the chordae tendonae

Front 9

What occurs during ventricular diastole?

Back 9

The pressure in the ventricles lowers, allowing the AV valves to open

The semilunar valves close to prevent blood from flowing back into the ventricles from the higher pressure aorta and pulmonary trunk.

Blood begins to flow into the ventricles from the atria

Front 10

What term is used to describe heart sounds?

Back 10

Lub-Dub

Front 11

Lub

Back 11

Refers to the closure of the AV valves

Front 12

Dub

Back 12

Refers to the closure of the semilunar valves

Front 13

What are the specialized areas that are specially adapted to initiate and conduct impulses?

Back 13

1. Sinoatrial Node

2. Atrioventricular node

3. Bundle of His

4. Purkinje fibers

Front 14

What is the name of the machine that records the electrical impulses of the heart?

Back 14

Electrocardiograph

Front 15

In response to electric impulses, the electrocardiograph produces a series of ____ that are recorded onto a ______

Back 15

Deflection waves

Electrocardiogram

Front 16

Types of deflection waves

Back 16

P wave

QRS complex

T wave

Front 17

P wave

Back 17

Records electrical activity associated with atrial depolarization

Front 18

QRS complex

Back 18

Ventricular depolarization (main deflection)

Atrial repolarization

Front 19

T wave

Back 19

Ventricular repolarization

Front 20

What controls the heart rate?

Back 20

Autonomic nervous system

Front 21

Divisions of your autonomic nervous system

Back 21

Sympathetic

Parasympathetic

Front 22

What carries sympathetic impulses?

Back 22

Accelerator nerves

Front 23

What carries parasympathetic impulses?

Back 23

Vagus nerve

Front 24

Cardiac muscle depolarization leads to ____

Back 24

Systole

Front 25

Cardiac repolarization leads to ______

Back 25

Diastole

Front 26

Deoxygenated blood

Back 26

High CO2, low O2

Pumped by the right side of the heart

Front 27

Oxygenated blood

Back 27

High O2, Low CO2

pumped by the left side

Front 28

Septum

Back 28

A partition separating the atria or the ventricles

Prevents the mixing of oxygenated and deoxygenated blood

Front 29

Name of septum separating the atria?

Back 29

Interatrial septum

Front 30

Name of the septum separating the ventricles?

Back 30

Interventricular septum

Front 31

Valves

Back 31

Prevent the backflow of blood

Front 32

How many valves are in the heart?

Back 32

4

Front 33

Heart sounds

Back 33

Produced by the closure of valves

Front 34

Potential cause of a murmur

Back 34

Sometimes caused by a leaking valve

Front 35

What are the exchange vessels?

Back 35

Capillaries

Front 36

What are the first arterial branches that come off of the ascending aorta?

Back 36

Branches to the coronary arteries

Front 37

What is the first structure the heart sends oxygenated blood?

Back 37

The heart

Front 38

Where do the coronary arteries deliver blood?

Back 38

Myocardium

Front 39

Characteristics of cardiac muscle

Back 39

Single, rounded nucleus in striated cells

Intercolated discs

Many mitochondria

High concentration of myoglobin

Totally dependent on aerobic metabolism

Front 40

Intercolated discs

Back 40

Thickenings of the cell membrane

Strengthen the muscle tissue

Aid in nerve impulse conduction over the muscle tissue

Front 41

What are mitochondria used for?

Back 41

ATP production

Front 42

Myoglobin

Back 42

Compound that stores O2

Front 43

CAD

Back 43

Coronary artery disease

Front 44

Artherosclerosis

Back 44

Plaque build up in the coronary arteries

Front 45

Plaque

Back 45

Fatty deposits that calcify

Front 46

Calcification

Back 46

Hardening

Front 47

Angina pectoris

Back 47

Chest pain caused by insufficient O2 to the heart muscle

Front 48

Arterial sclerosis

Back 48

A loss of elasticity (or hardening) of the coronary arteries

Front 49

Myocardial Infarction

Back 49

Aka heart attack

Most commonly caused by a blood clot

Front 50

Heart reflexes that affect cardio output

Back 50

Atrial (bainbridge) reflex

Starling principle

Front 51

Atrial Reflex

Back 51

- Aka Bainbridge reflex

- Occurs when an increase in blood volume is detected within the atria, causing the walls to stretch

- increases sympathetic activity, which increases heart rate

Front 52

Starling Principle

Back 52

- Occurs when an increase in blood volume is detected within the ventricles, which causes the walls to stretch

- increases the force of contraction of ventricular myocardium

Front 53

Heart rate

Back 53

Number of beats per minute

Front 54

Average heart rate

Back 54

80bpm

Front 55

Stroke volume

Back 55

Amount of blood pumped by the ventricle in a single contraction

Front 56

Average stroke volume

Back 56

80ml/beat

Front 57

Cardiac Output (CO)

Back 57

Amount of blood pumped by the ventricle in one minute

Calculated CO ( L/min) = HR x SV

Front 58

Effect of beta stimulation?

Back 58

Excitatory

Increase in HR, SV, and CO

Front 59

Where is the cardiac center located?

Back 59

The brainstem, specifically in the medulla

Front 60

Parts of the cardiac center

Back 60

Cardioacceleratory center

Cardioinhibitory center

Front 61

Cardioacceleratory center

Back 61

Increases heart activity

Front 62

Cardioinhibitory center

Back 62

Slows heart activity

Front 63

What gland secretes which hormones involved in the sympathetic activity of the heart?

Back 63

Adrenal gland

Norepinephrine (this is the relevant hormone) and Epinephrine

Front 64

Back 64

Acetylcholine

Front 65

Back 65

Post Ganglionic Neuron

Front 66

Back 66

Preganglionic neuron