BIO122 OTHER HEART/CIRCULATORY RELATED SHIT

intercalated discs

where cardiac muscle cells are connected, allows for communication between cells

functional syncytium

heart contracts as one unit

what does it mean by the heart beats intrinsically?

it doesn't need external stimulation to contract

intrinsic conduction system/nodal system

controls the rhythmic heartbeat

components of the intrinsic conduction system

sinoatrial (SA) node (pacemaker), atrioventricular (AV) node, atrioventricular bundle (bundle of His), bundle branches, purkinje fibers

sinoatrial (SA) node (pacemaker)

in the right atrium, initiates electrical impulses, which causes atrial depolarization (P wave)

atrioventricular (AV) node

in the junction of atria and ventricles, allows ventricles to fill before contraction

atrioventricular (AV) bundle (bundle of His)

transmits impulses from AV node to interventricular septum

bundle branches

conduct impulses down the interventricular septum toward the apex

purkinje fibers

spread impulses throughout the ventricular myocardium and helps pump blood

'electrocardiogram (EKG/ECG)

graphic recording of the electrical activity of the heart

'the instrument that records the electrical activity of the heart is called an

electrocardiogram

what are the 3 deflection waves of an electrocardiogram

P wave, QRS complex, and T wave

P wave

atrial depolarization

QRS complex

ventricular depolarization

T wave

ventricular repolarization

'rhythmicity

spontaneous depolarization and repolarization in the cardiac muscle

which nervous system is the heart innervated by

autonomic nervous system

'what is the effect of parasympathetic and sympathetic nervous system control on the heart

decreases HR and increases HR, respectively

'tachycardia

resting heart rate over 100 bpm, normal during periods of exercise

'bradycardia

resting heart rate under 60 bpm, normal in athletes

'cardiac cycle

one complete heart beat, contraction and relaxation of the atria and ventricles

'cardiac impairment

indication of a large pulse deficit (ex: strong apical heart rate, weak radial pulse)

during diastole

ventricular relaxation/filling/repolarization. blood flows from the atria to the ventricles. the AV valves open and the semilunar valves are closed

atrial contraction

sends residual blood into the ventricles

during systole

the heart is contracting, AV valves are closed and the semilunar valves are open

dichrotic notch

pressure fluctuation as the aortic semilunar valve closes

what is the average HR

72 BPM, normal is 60 to 100 BPM

how long does atrial contraction, ventricular contraction, and relaxation take

0.1 for atria, 0.3 for ventricular, total cardiac cycle (atrial + ventricular + relaxation) takes 0.4 seconds

'pacemakers appearing erratically and at abnormal sites in the heart muscle are called

ectopic pacemakers

'hyperkalemia

larger than normal concentration of potassium outside of the cells, causes weakened contractile strength

'the ___ of the heart consists of specialized noncontractile myocardial tissue that exerts control on the rhythmic beating of the heart

intrinsic conduction system

what is the SA node often referred to as because it keep the heart beating at a stable rate

pacemaker

'excessive vagal stimulation that stop the heart, after which the ventricles will begin to contract again is known as

vagal escape

'give one reason why vagal escape may occur

sympathetic reflexes

'what happens to the heart when bathed in solution with atropine sulfate

increased HR

'what happens to the heart when bathed in solution with cold ringer's

decreased HR

warm ringer's solution

speeds up HR

cold ringer's solution

slows down HR

'what happens to the heart when bathed in solution with sodium ions

weakened contractile strength

'what happens to the heart when bathed in solution with potassium ions

weakened contractile strength

'what happens to the heart when bathed in solution with digitalis

slow and steady contraction

'what happens to the heart when bathed in epinephrine

increased HR

calcium ions

increases contractile strength

pilocarpine

slows down HR

atropine sulfate

antagonist of pilocarpine, speeds up HR

'heart murmurs

abnormal heart sounds, indicates problems like back flow of blood or aortic stenosis

'name the two sounds that can be heard during the cardiac cycle

S1 (lub)(loudest) and S2 (dup)

'the lub heard when listening to the heart sounds is caused by the closure of what valves

AV valves

'the dup heard when listening to heart sounds is caused by the closure of what valves

semilunar valves

'where is the best place to auscultate heart sounds

left sternal border at the fifth intercostal space

pulse

due to contraction and relaxation of the left ventricle. pulse rate matches the heart rate

places to palpate the pulse

carotid artery, temporal artery, facial artery, brachial artery, radial artery, femoral artery, popliteal artery, post tibial artery, dorsalis pedis artery

apical pulse

obtained by counting heart beats at the apex

'pulse deficit

difference between the apical heart rate and radial pulse rate

'fibrillation

condition of rapid uncoordinated contractions

'name a superficial artery where the pulse is easily palpated

carotid artery, brachial artery

'blood pressure

the pressure blood exerts against the arteries

'systolic pressure

pressure during ventricular contraction/depolarization

'diastolic pressure

pressure during ventricular relaxation/refilling

'the pressure fluctuation due to the shutting of the aortic semilunar valve, which causes a momentary increase in aortic pressure due to elastic recoil of the aorta is called the

dichrotic notch

'during blood pressure reading, as pressure in the sphygmomanometer is slowly released, the ___ are heard

korotkoff sounds

'sphygmomanometer

instrument used to measure blood pressure

'pulse pressure =

systolic pressure - diastolic pressure

hyporeactors (normal)

have a rise or fall of diastolic or systolic pressure of between 0 and 22mmHg

hyperreactors

have a rise or fall of 22 or more mmHg of diastolic or systolic pressure

nicotine

causes vasoconstriction and a rise in blood pressure

'the blood pressure test in which one hand is immersed in very cold water is called the

cold pressor test

'during the cold pressor test, subjects that have a rise of diastolic or systolic pressure of 22mm Hg or more, which isn't normal, are called

hyperreactors

'during the cold pressor test, subjects that have a rise or fall of diastolic or systolic pressure between 0 and 22mm Hg, which is normal, are called

hyporeactors

'factors that may affect blood pressure

age, smoking, exercise, stress

'what is the systolic pressure of a person with a diastolic pressure of 40mm Hg and and MAP of 60mm Hg

100 mm Hg

'mean arterial pressure (MAP) calculation

(SBP + 2(DBP))/3

MAP for diastolic of 80mm Hg and systolic of 140mm Hg

100 mm Hg (140 + 2(80) / 3)

skin color

indication of circulation through an artery. less circulation = vessel constricted, more circulation = vessel dilated

'flare of skin

redness due to mechanical stimulation of the skin, due to inflammation caused by tissue injury (indian burn)

dermographism

skin sensitivity leading to swelling

wheal

swollen area due to mechanical stimulation

'skin sensitivity leading to swelling at the point of mechanical stimulation is called

dermatographism

'factors that influence skin color

oxygen supply, temperature, hormones, substances released by injured tissues