Question 1

Which cardiac cell characteristic function is mechanical?&#10;A) Automaticity&#10;B) Excitability&#10;C) Conductivity&#10;D) Contractility

Accepted Answer

Contractility refers to the ability of cardiac cells to contract and generate force, which is a mechanical function. Automaticity refers to the ability of cardiac cells to spontaneously generate electrical impulses, excitability refers to the ability of cells to respond to electrical stimuli, and conductivity refers to the ability of cells to transmit electrical impulses. While these functions are important for the overall function of the heart, they are not solely mechanical in nature.

Question 2

During the absolute refractory period the cardiac cell:&#10;A) cannot be stimulated.&#10;B) can be stimulated.&#10;C) can be stimulated if stimulus is strong enough.&#10;D) can only contract.

Accepted Answer

During the absolute refractory period, the cardiac cell cannot be stimulated, meaning it is not responsive to any stimulus regardless of its strength. This is due to the inactivation of sodium channels, which are responsible for depolarization and excitation of the cell. Therefore, the cell cannot contract or generate any action potential during this period.

Question 3

Automaticity is the ability of cardiac pacemaker cells to:&#10;A) generate their own impulses without external stimulation.&#10;B) respond to an electrical stimulus.&#10;C) receive an electrical impulse.&#10;D) cause cardiac muscle contraction.

Accepted Answer

Automaticity refers to the ability of pacemaker cells to generate their own impulses without external stimulation, as they possess a special membrane property called depolarization. This property allows them to spontaneously depolarize and generate an action potential that leads to cardiac muscle contraction.

Question 4

The cation that is extracellular is:&#10;A) potassium.&#10;B) calcium.&#10;C) sodium.&#10;D) magnesium.

Accepted Answer

Sodium is a cation (positively charged ion) that is predominantly found in extracellular fluid, while potassium is predominantly found inside cells. Calcium and magnesium are also cations, but they are not predominantly found in the extracellular fluid.

Question 5

The ability of the cell membrane to change to allow the movement of ions is called:&#10;A) permeability.&#10;B) changeability.&#10;C) polarity.&#10;D) amorality.

Accepted Answer

Permeability refers to the ability of the cell membrane to allow certain substances, such as ions, to pass through. The membrane can change its permeability through various mechanisms, including the opening and closing of ion channels. Therefore, option A is the correct answer. Option B, changeability, is not a commonly used term in biology and is not specifically related to the movement of ions across the cell membrane. Option C, polarity, refers to the distribution of electric charge across a molecule, and is not directly related to the ability of the cell membrane to allow ion movement. Option D, amorality, is a term related to ethics and morality and is not relevant to this context.

Question 6

All of the following cations affect cardiac function EXCEPT:&#10;A) potassium.&#10;B) sodium.&#10;C) calcium.&#10;D) chloride.

Accepted Answer

Chloride (Cl-) is an anion and does not directly affect cardiac function as compared to cations such as potassium (K+), sodium (Na+), and calcium (Ca2+).

Question 7

A decrease in calcium blood levels is termed:&#10;A) hyponatremia.&#10;B) hypercalcemia.&#10;C) hypocalcemia.&#10;D) hypokalemia.

Accepted Answer

Hypocalcemia refers to a decrease in calcium blood levels.

Question 8

An increase in potassium levels is known as:&#10;A) hyperkalemia.&#10;B) hypernatremia.&#10;C) hypokalemia.&#10;D) hypercalcemia.

Accepted Answer

Hyperkalemia refers to abnormally high levels of potassium in the blood.

Question 9

Cells responsible for generating the physical contraction of the heart muscle are the:&#10;A) specialized pacemaker cells.&#10;B) contractile cells.&#10;C) Both are responsible.&#10;D) None are responsible.

Accepted Answer

The contractile cells are responsible for generating the physical contraction of the heart muscle, whereas specialized pacemaker cells are responsible for initiating and regulating the heartbeat.

Question 10

An ion with a negative charge is called a(n):&#10;A) anion.&#10;B) cation.&#10;C) neuron.&#10;D) syncytia.

Accepted Answer

An ion with a negative charge is called an anion.

Question 11

The specialized pacemaker cells contain contractile filaments.&#10;A) False&#10;B) True

Accepted Answer

The answer of The specialized pacemaker cells contain contractile filaments.&#10;A)...

Question 12

The term that is also referred to as irritability is:&#10;A) contractility.&#10;B) automaticity.&#10;C) excitability.&#10;D) conductivity.

Accepted Answer

The answer of The term that is also referred to...

Question 13

During the resting period, what type of line is recorded on the EKG strip?&#10;A) Baseline&#10;B) Positive deflection&#10;C) Negative deflection&#10;D) Artifact

Accepted Answer

The answer of During the resting period, what type of...

Question 14

The ________ cells have the ability to create an electrical impulse without being stimulated by a nerve.&#10;A) myocardial contract&#10;B) myocardial conduct&#10;C) myocardial excitable&#10;D) myocardial pacemaker

Accepted Answer

The answer of The ________ cells have the ability to...

Question 15

During the polarized or resting state, the inside of the cell is electrically:&#10;A) positive.&#10;B) negative.&#10;C) neutral.&#10;D) positive and negative.

Accepted Answer

The answer of During the polarized or resting state, the...

Question 16

An ion with a positive charge is called a(n):&#10;A) anion.&#10;B) cation.&#10;C) neuron.&#10;D) syncytia.

Accepted Answer

The answer of An ion with a positive charge is...

Question 17

The term threshold refers to the point at which a ________ will produce a cell response.&#10;A) current&#10;B) receptor&#10;C) contraction&#10;D) stimulus

Accepted Answer

The answer of The term threshold refers to the point...

Deck 3: Basic Electrophysiology