Question 1

Which protein(s) is/are responsible for development of the resting membrane potential?

Accepted Answer

A)  leak channels. 
B)  gated channels. 
C)  pumps. 
D)  both (a) and (b) above. 
E)  both (a) and (c) above. 
A)  leak channels. 
B)  gated channels. 
C)  pumps. 
D)  both (a) and (b) above. 
E)  both (a) and (c) above.

Question 2

The following question refers to comparative concentrations, permeabilities, and potentials under various circumstances. Indicate the relationship between the two items listed in each situation by filling the appropriate letter in the blank using the following answer code:
-A. concentration of Na+ in the extracellular fluid
B. concentration of Na+ in the intracellular fluid of a nerve cell immediately following an action potential (assume that the Na+-K+ pump has not yet acted)

Accepted Answer

A) A is greater than B. 
B) B is greater than A. 
C) A and B are equal. 
A) A is greater than B. 
B) B is greater than A. 
C) A and B are equal.

Question 3

Myelinated fibers conduct impulses about ____________________ times faster than unmyelinated fibers of the same diameter.

Accepted Answer

The answer of Myelinated fibers conduct impulses about ____________________ times...

Question 4

Which of the following channels opens or closes in response to changes in membrane potential?

Accepted Answer

A)  voltage-gated 
B)  chemical-gated 
C)  mechanically-gated 
D)  thermally-gated 
E)  none of these answers. 
A)  voltage-gated 
B)  chemical-gated 
C)  mechanically-gated 
D)  thermally-gated 
E)  none of these answers.

Question 5

During the peak of the action potential which ion has the greatest permeability?

Accepted Answer

A)  sodium. 
B)  potassium. 
C)  calcium. 
D)  chloride. 
E)  protein. 
A)  sodium. 
B)  potassium. 
C)  calcium. 
D)  chloride. 
E)  protein.

Question 6

Permeability of which ion is affected by a positive feedback mechanism once threshold is reached?

Accepted Answer

A)  sodium. 
B)  potassium. 
C)  calcium. 
D)  chloride. 
E)  protein. 
A)  sodium. 
B)  potassium. 
C)  calcium. 
D)  chloride. 
E)  protein.

Question 7

Saltatory conduction

Accepted Answer

A)  occurs in unmyelinated nerve fibers. 
B)  is slower than conduction by local current flow because the myelin acts as an insulator to slow the impulse down. 
C)  involves the impulse jumping from one node of Ranvier to the adjacent node. 
D)  refers to the action potential spreading from one Schwann cell to the adjacent Schwann cell. 
E)  more than one of these answers. 
A)  occurs in unmyelinated nerve fibers. 
B)  is slower than conduction by local current flow because the myelin acts as an insulator to slow the impulse down. 
C)  involves the impulse jumping from one node of Ranvier to the adjacent node. 
D)  refers to the action potential spreading from one Schwann cell to the adjacent Schwann cell. 
E)  more than one of these answers.

Question 8

When an action potential is over and the membrane has returned to resting potential, the voltage-gated sodium channel:

Accepted Answer

A)  is closed and not capable of opening 
B)  is closed and capable of opening 
C)  is open 
D)  open and not capable of closing 
E)  two of these answers. 
A)  is closed and not capable of opening 
B)  is closed and capable of opening 
C)  is open 
D)  open and not capable of closing 
E)  two of these answers.

Question 9

MATCHING
Indicate the direction that the force in question tends to move the involved ion under the stated conditions by writing the appropriate letter in the blank, using the following answer code:
-concentration gradient for Na+ at threshold potential

Accepted Answer

A) This force tends to move the involved ion out of the cell. 
B) This force tends to move the involved ion into the cell. 
A) This force tends to move the involved ion out of the cell. 
B) This force tends to move the involved ion into the cell.

Question 10

Indicate whether the membrane is more permeable to KS1U1P1+S1S1P0 or to NaS1U1P1+S1S1P0 or is equally permeable to these ions under the stated conditions by writing the appropriate letter in the blank using the following answer code:
-during the rising phase of an action potential

Accepted Answer

A) The membrane is more permeable to K+ than to Na+. 
B) The membrane is more permeable to Na+ than to K+. 
C) The membrane is about equally permeable to Na+ and K+. 
A) The membrane is more permeable to K+ than to Na+. 
B) The membrane is more permeable to Na+ than to K+. 
C) The membrane is about equally permeable to Na+ and K+.

Question 11

Which statement is characteristic of the endocrine system?

Accepted Answer

A)  it is considered "wireless" 
B)  utilizes neurotransmitters 
C)  is effective over short distances 
D)  has a rapid response 
E)  coordinates precise responses 
A)  it is considered "wireless" 
B)  utilizes neurotransmitters 
C)  is effective over short distances 
D)  has a rapid response 
E)  coordinates precise responses

Question 12

Specialization of target-cell receptors explains the specificity of hormonal action.

Accepted Answer

A) True 
 B)False

Question 13

____________________ are the myelin-forming cells in the central nervous system, whereas ____________________ are the myelin-forming cells in the peripheral nervous system.

Accepted Answer

oligodendr

Question 14

The accompanying figure relates to neurotransmitter secretion. Match the steps highlighted in the figure (steps 1-5) with the statements using the letter key below.
-Calcium enters synaptic knob

Accepted Answer

A) Step 1 
B) Step 2 
C) Step 3 
D) Step 4 
E) Step 5 
A) Step 1 
B) Step 2 
C) Step 3 
D) Step 4 
E) Step 5

Question 15

When a neuron starts to depolarize, ____________________ ions move into the cell.

Accepted Answer

The answer of When a neuron starts to depolarize, ____________________...

Question 16

As the stimulus strength increases, the amplitude of a graded potential decreases.

Accepted Answer

A) True 
 B)False

Question 17

Describe how second messenger system amplification occurs.

Accepted Answer

Second messenger cascades can produce an

Question 18

Lipophilic hormones must interact with which of the following prior to gene activation?

Accepted Answer

A)  membrane receptors. 
B)  molecular chaperones. 
C)  hormone response elements. 
D)  both (a) and (b) above. 
E)  both (b) and (c) above. 
A)  membrane receptors. 
B)  molecular chaperones. 
C)  hormone response elements. 
D)  both (a) and (b) above. 
E)  both (b) and (c) above.

Question 19

Lipophilic hormones

Accepted Answer

A)  include steroids and thyroid hormone. 
B)  bind with receptors located inside their target cells. 
C)  activate second-messenger systems within their target cells. 
D)  both (a) and (b) above. 
E)  all of these answers. 
A)  include steroids and thyroid hormone. 
B)  bind with receptors located inside their target cells. 
C)  activate second-messenger systems within their target cells. 
D)  both (a) and (b) above. 
E)  all of these answers.

Question 20

The cells of excitable and nonexcitable tissues share which of the following properties?

Accepted Answer

A)  a threshold potential 
B)  a resting membrane potential 
C)  an ability to open the Na+ gates 
D)  all of these answers. 
E)  none of these answers. 
A)  a threshold potential 
B)  a resting membrane potential 
C)  an ability to open the Na+ gates 
D)  all of these answers. 
E)  none of these answers.

Which protein(s) is/are responsible for development of the resting membrane potential?

Myelinated fibers conduct impulses about ____________________ times faster than unmyelinated fibers of the same diameter.

Which of the following channels opens or closes in response to changes in membrane potential?

During the peak of the action potential which ion has the greatest permeability?

Permeability of which ion is affected by a positive feedback mechanism once threshold is reached?

Saltatory conduction

When an action potential is over and the membrane has returned to resting potential, the voltage-gated sodium channel:

MATCHING Indicate the direction that the force in question tends to move the involved ion under the stated conditions by writing the appropriate letter in the blank, using the following answer code: -concentration gradient for Na⁺ at threshold potential

Indicate whether the membrane is more permeable to K⁺ or to Na⁺ or is equally permeable to these ions under the stated conditions by writing the appropriate letter in the blank using the following answer code: -during the rising phase of an action potential

Which statement is characteristic of the endocrine system?

Specialization of target-cell receptors explains the specificity of hormonal action.

are the myelin-forming cells in the central nervous system, whereas are the myelin-forming cells in the peripheral nervous system.

The accompanying figure relates to neurotransmitter secretion. Match the steps highlighted in the figure (steps 1-5) with the statements using the letter key below. -Calcium enters synaptic knob

When a neuron starts to depolarize, ____________________ ions move into the cell.

As the stimulus strength increases, the amplitude of a graded potential decreases.

Describe how second messenger system amplification occurs.

Lipophilic hormones must interact with which of the following prior to gene activation?

Lipophilic hormones

The cells of excitable and nonexcitable tissues share which of the following properties?

Introduction to Physiology and Homeostasis

Cell Physiology

The Plasma Membrane and Membrane Potential

The Central Nervous System

The Peripheral Nervous System: Afferent Division and Special Senses

The Peripheral Nervous System: Efferent Division

Muscle Physiology

Cardiac Physiology

The Blood Vessels and Blood Pressure

The Blood and Body Defenses

The Respiratory System

The Urinary System

Fluid and Acid-Base Balance

The Digestive System

Energy Balance and Temperature Regulation

The Endocrine System

The Reproductive System

Filters

Exam 4: Principles of Neural and Hormonal Communication

Which protein(s) is/are responsible for development of the resting membrane potential?

Myelinated fibers conduct impulses about ____________________ times faster than unmyelinated fibers of the same diameter.

Which of the following channels opens or closes in response to changes in membrane potential?

During the peak of the action potential which ion has the greatest permeability?

Permeability of which ion is affected by a positive feedback mechanism once threshold is reached?

Saltatory conduction

When an action potential is over and the membrane has returned to resting potential, the voltage-gated sodium channel:

MATCHING Indicate the direction that the force in question tends to move the involved ion under the stated conditions by writing the appropriate letter in the blank, using the following answer code: -concentration gradient for Na+ at threshold potential

Indicate whether the membrane is more permeable to K+ or to Na+ or is equally permeable to these ions under the stated conditions by writing the appropriate letter in the blank using the following answer code: -during the rising phase of an action potential

Which statement is characteristic of the endocrine system?

Specialization of target-cell receptors explains the specificity of hormonal action.

____________________ are the myelin-forming cells in the central nervous system, whereas ____________________ are the myelin-forming cells in the peripheral nervous system.

The accompanying figure relates to neurotransmitter secretion. Match the steps highlighted in the figure (steps 1-5) with the statements using the letter key below. -Calcium enters synaptic knob

When a neuron starts to depolarize, ____________________ ions move into the cell.

As the stimulus strength increases, the amplitude of a graded potential decreases.

Describe how second messenger system amplification occurs.

Lipophilic hormones must interact with which of the following prior to gene activation?

Lipophilic hormones

The cells of excitable and nonexcitable tissues share which of the following properties?

Introduction to Physiology and Homeostasis

Cell Physiology

The Plasma Membrane and Membrane Potential

The Central Nervous System

The Peripheral Nervous System: Afferent Division and Special Senses

The Peripheral Nervous System: Efferent Division

Muscle Physiology

Cardiac Physiology

The Blood Vessels and Blood Pressure

The Blood and Body Defenses

The Respiratory System

The Urinary System

Fluid and Acid-Base Balance

The Digestive System

Energy Balance and Temperature Regulation

The Endocrine System

The Reproductive System

Filters

MATCHING Indicate the direction that the force in question tends to move the involved ion under the stated conditions by writing the appropriate letter in the blank, using the following answer code: -concentration gradient for Na⁺ at threshold potential

Indicate whether the membrane is more permeable to K⁺ or to Na⁺ or is equally permeable to these ions under the stated conditions by writing the appropriate letter in the blank using the following answer code: -during the rising phase of an action potential

are the myelin-forming cells in the central nervous system, whereas are the myelin-forming cells in the peripheral nervous system.