Lab 7

Question 1

The pacemaker region of the heart is the

Answer 1

SA Node

Question 2

The conducting tissue of the heart located in the inter ventricular septum is the

Answer 2

Bundle of His

Question 3

P Wave

Answer 3

Depolarization of Atria

Question 4

ORS Complex/Wave

Answer 4

Depolarization of Ventricles

Question 5

T Wave

Answer 5

Repolarization of Ventricles

Question 6

The electrical synapses between adjacent myocardial cells called

Answer 6

gap junctions

Question 7

An abnormally fast rate of beat

Answer 7

Tachycardia

Question 8

An abnormally slow rate

Answer 8

Bradycardia

Question 9

An abnormally long PR interval indicates a condition

Answer 9

1st degree heart block

Question 10

Which ECG wave must occur before the ventricles can contract?

Answer 10

QRS

Question 11

Which ECQ wave must occur before the ventricles can relax?

Answer 11

T Wave

Question 12

What could cause an increase in the peripheral resistance in a blood vessel?

Answer 12

a clogged artery

Question 13

ventricular contraction

Answer 13

systole

Question 14

the amount of blood each ventricle pumps per minute

Answer 14

cardiac output

Question 15

the amount of blood pumped to the body per contraction per ventricle

Answer 15

stroke volume

Question 16

the volume of the blood in the heart at the end of ventricular contraction

Answer 16

end systolic volume

Question 17

ventricular relaxation

Answer 17

diastole

Question 18

contraction that occurs when the volume of blood in the ventricles remains constant

Answer 18

isovolumetric contraction

Question 19

the volume of blood in the heart at the end of ventricular relaxation

Answer 19

end diastolic volume

Question 20

the ejection of blood near the end of systole during which ventricular pressure rises and then begins to decline

Answer 20

ventricular ejection

Question 21

Frank Starlings Law

Answer 21

When the rate @ which blood returns to the heart changes, the heart will adjust its output to match the change in flow.

Question 22

What variable had the strongest effect on fluid flow?

Answer 22

Radius

Question 23

What would occur if the left side of the heart pumped faster than the right side?

Answer 23

Blood would soon empty from the heart, and stroke volume would fall greatly.

Question 24

The sympathetic nervous system releases the neurotransmitter

Answer 24

Norepinephrine

Question 25

The PNS releases the neurotransmitter

Answer 25

Acetylcholine

Question 26

The Symmpatheic NS _______ heart rate

Answer 26

increases

Question 27

The PNS ________ heart rate

Answer 27

decreases

Question 28

Autorhytmicity

Answer 28

the hearts ability to trigger its own contractions

Question 29

SA node

Answer 29

the pacemaker of the heart, where the cardiac cells with the fastest contraction rates join together

Question 30

Pacemaker cells

Answer 30

cells in the SA node

Question 31

Vagus nerves

Answer 31

cranial nerve that delivers PNS input to the heart

Question 32

Difference between cardiac muscle and skeletal muscle

Answer 32

Cardiac muscle displays autorhythmicity, skeletal muscle does not. Cardiac muscle has a relative long refactory period, skeletal muscle has a relative short refractory period.

Question 33

Epinephrine

Answer 33

increases heart rate and strengthens contractions

Question 34

Pilocarpine

Answer 34

decreases heart rate, mimics AcH

Question 35

atropine

Answer 35

increases heart rate, inhibits AcH

Question 36

Digitalis

Answer 36

decreases heart rate, blocks conduction of atrial impulses to the ventricles

Question 37

Ca2+

Answer 37

induces irregular heart rate, increases strength of contraction

Question 38

Na+

Answer 38

induces irregular heart rate; decreases strength and rate of contraction

Question 39

K+

Answer 39

intially causes heart rate to decrease then causes it to become irregular; weakens contractions

Question 40

SA Node

Answer 40

Pacemaker of the heart, origin of electrical signal causing heart to contract

Question 41

AV Node

Answer 41

delays the AP's before sending the AP to the bundles of HIS (ensures atrias have fully contracted before the ventricles)

Question 42

R & L bundle branches

Answer 42

Directs the AP to base of the ventricles (lay within the interventricular septum)

Question 43

Purkinje Fiber

Answer 43

Receives stimulus from bundle branches and stimulate the ventricles from bottom to top direction

Question 44

Bundle of His

Answer 44

electrical connection between atrias and ventricles

Question 45

Why is atrial repolarization masked by ORS complex

Answer 45

Because of mass differences between atrias and ventricles

Question 46

What changes are normal between pre and post exercise ECG's and what parameter should never change!

Answer 46

Heart Rate changes. Ventricular diastole: the time between the peak of the T wave to the next ORS complex (ventricles are compeltely relaxed - should change). PR should never change this represents how long it takes the signal from the Atria to ventricles

Question 47

Systolic Pressure

Answer 47

Pressure generated by the contracting ventricles

Question 48

Diastolic Pressure

Answer 48

Pressure in the system when the ventricles are relaxed

Question 49

MAP

Answer 49

Diastolic Pressure + 1/3 (Pulse Pressure

Question 50

Pulse Pressure

Answer 50

Systolic-Diastolic

Question 51

The scientific term for insufficient blood flow to the heart is called ...

Answer 51

Ischemia