Question 1

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

Accepted Answer

The term threshold refers to the point at which a stimulus will produce a cell response, particularly in the context of nerve cells or muscle cells, where a certain level of stimulus is required to trigger an action potential or a contraction.

Question 2

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

Accepted Answer

During the absolute refractory period, the cardiac cell is completely unresponsive to any stimulus, no matter how strong it is. This is due to the fact that the voltage-gated sodium channels responsible for the depolarization phase are inactivated, and cannot be reopened until the membrane potential returns to its resting state. Therefore, the correct answer is that the cardiac cell cannot be stimulated during the absolute refractory period.

Question 3

The specialized pacemaker cells contain contractile filaments.

Accepted Answer

The specialized pacemaker cells do not contain contractile filaments. They are responsible for generating electrical impulses that cause the heart muscle to contract, but they do not themselves contract. Contractile filaments are found in the muscle fibers of the heart.

Question 4

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

Accepted Answer

A cation is an ion that has a positive charge due to having more protons than electrons.

Question 5

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

Accepted Answer

Hypocalcemia is a term used to describe a decrease in calcium levels in the blood. Hypercalcemia is the opposite, with an increase in calcium levels. Hyponatremia refers to a decrease in sodium levels, and hypokalemia refers to a decrease in potassium levels, which are different electrolytes than calcium.

Question 6

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

Accepted Answer

During the polarized or resting state, the inside of the cell is negatively charged in comparison to the outside. This is due to the presence of negatively charged ions, such as proteins and phosphates, inside the cell and positively charged ions, such as sodium and potassium ions, outside the cell.

Question 7

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

Accepted Answer

An anion is an ion with a negative charge.

Question 8

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

Accepted Answer

Sodium is the main extracellular cation in the body, while potassium is the main intracellular cation. Magnesium and calcium are also important cations in the body, but they are primarily found inside cells or in extracellular compartments like bone.

Question 9

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

Accepted Answer

An increase in potassium levels in the blood is known as hyperkalemia.

Question 10

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

Accepted Answer

The answer of Cells responsible for generating the physical contraction...

Question 11

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

Accepted Answer

The answer of All of the following cations affect cardiac...

Question 12

The primary function of the myocardial working cell is contraction only.

Accepted Answer

The answer of The primary function of the myocardial working...

Question 13

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

Accepted Answer

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

Question 14

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

Accepted Answer

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

Question 15

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

Accepted Answer

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

Question 16

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

Accepted Answer

The answer of The ability of the cell membrane to...

Question 17

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

Accepted Answer

The answer of Automaticity is the ability of cardiac pacemaker...

Question 18

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

Accepted Answer

The answer of Which cardiac cell characteristic function is mechanical?&#10;A)...

Deck 3: Basic Electrophysiology