Question

QUESTION 1

1. The ---------------- of a neuron gather information (from other neurons or from the environment) and turn it into a localized electrical signal called ----------------.

   	A.	dendrites; graded potentials
   	B.	axon terminal; neurotransmitters
   	C.	axon hillock; exocytosis
   	D.	cell body; action potentials
   	E.	axons; graded potentials

2.5 points   

QUESTION 2

1. Sensory neurons are also known as -------------- neurons and relay information toward the CNS. Whereas motor neurons are also known as ---------- neurons and relay information away from the CNS toward the effector tissue.

   	A.	afferent; efferent
   	B.	inter-; efferent
   	C.	inter-; afferent
   	D.	afferent; inter-
   	E.	efferent; afferent

2.5 points   

QUESTION 3

1. The function of myelin is to...

   (Select all correct answers)

   	A.	none of these are correct
   	B.	insulate nerve fibers (axons)
   	C.	phagocytize microorganisms
   	D.	increase transmission speed of action potentials

2.5 points   

QUESTION 4

1. Which of the following is/are true concerning the function of the nervous system? (Choose all that are correct.)

   	A.	integrative function integrates, analyzes, and stores information
   	B.	motor function elicits proper response
   	C.	integrative function detects internal and external stimuli
   	D.	motor function of the nervous system integrates, analyzes, and stores information
   	E.	sensory function of the nervous system detects internal and external stimuli

2.5 points   

QUESTION 5

1. The spaces between myelination are called:

   	A.	oligodendrocytes
   	B.	satellite cells
   	C.	schwann cells
   	D.	nodes of ranvier
   	E.	saltatory conduction

2.5 points   

QUESTION 6

1. During a relative refractory period of an action potential

   	A.	Another action potential can be fired, it just takes a greater stimulus for the membrane potential to reach threshold
   	B.	Na+ channels are either already open or are inactivated therefore the membrane absolutely can not produce another action potential, no matter how intense the stimulus
   	C.	Ca++ flows out of the cell, causing hyperpolarization and a need for a greater stimulus to generate the action potential
   	D.	The presynaptic neuron "tells" the postsynaptic neuron about the "relative" strength of signal
   	E.	None of the above are correct

2.5 points   

QUESTION 7

1. Which ion channel opens/closes in response to a chemical (ex. neurotransmitter, drug, hormone) binding to it?

   	A.	leak channels
   	B.	ligand gated channels
   	C.	voltage gated channels
   	D.	mechanically gated channels

2.5 points   

QUESTION 8

1. A graded potential that moves the membrane potential further away from threshold is:

   	A.	action potential
   	B.	resting membrane potential
   	C.	depolarization
   	D.	hyperpolarization
   	E.	excitation

2.5 points   

QUESTION 9

1. Acetylcholinesterase is:

   	A.	An enzyme present on both the postsynaptic membrane and in the synaptic cleft; it inactivates acetylcholine by breaking it into acetate and choline.
   	B.	An enzyme present in the postsynaptic membrane and in the synaptic cleft which inactivates the catecholamines.
   	C.	An enzyme responsible for making acetylcholine from acetate and choline.
   	D.	An enzyme responsible for converting dopamine into norepinephrine.
   	E.	Two of the above are correct.

2.5 points   

QUESTION 10

1. Rank the following, based on speed of Action Potential conduction (propagation) through the axon, from slowest to fastest.

         -       I.       II.       III.       IV.         

   myelinated axon with a diameter of 20 micrometers

   
         -       I.       II.       III.       IV.         

   unmyelinated axon with a diameter of 10 micrometers

   
         -       I.       II.       III.       IV.         

   myelinated axon with a diameter of 12 micrometers

   
         -       I.       II.       III.       IV.         

   unmyelinated axon with a diameter of 2 micrometers

2.5 points   

QUESTION 11

1. Which of the following is true of the Nodes of Ranvier?

   	A.	They are produced by microglia in the central nervous system and satellite cells in the peripheral nervous system.
   	B.	They are located along the axon of a neuron and have a high concentration of voltage-gated Ca++ channels.
   	C.	They are areas of myelination which prevent loss of charge across the plasma membrane of the neuron.
   	D.	They are located on neuronal axons, at the gaps between myelination. There is a high concentration of voltage gated Na+ channels and voltage gated K+ channels which allow for the production of action potentials at the Nodes of Ranvier.
   	E.	They increase the loss of charge along the plasma membrane of a neuron.

2.5 points   

QUESTION 12

1. Speed of conduction (propagation) of an action potential is increased by:

   	A.	increased diameter of an axon & myelination
   	B.	decreased diameter of an axon & myelination
   	C.	increased diameter of an axon & non-myelination
   	D.	decreased diameter of an axon & non-myelination
   	E.	none of the above

2.5 points   

QUESTION 13

1. Saltatory conduction is:

   	A.	The dissolving of salt (NaCl) into the blood, thereby affecting osmolarity of blood.
   	B.	Synaptic transmission about dietary intake of salt.
   	C.	The way two neurons communicate with each other-- information "jumps" back and forth from one neuron to another neuron.
   	D.	The apparent "jumping" of action potentials from node of ranvier to node of ranvier.
   	E.	A special name for the generation of an action potential down an unmyelinated axon.

2.5 points   

QUESTION 14

1. Which of the following is true of cholinergic receptors:

1. 	A.	Collectively
   	B.	Spatially
   	C.	Chronically
   	D.	Temporally
   	E.	Tonically

2.5 points   

QUESTION 40

1. One neuron synapses onto the dendrite of one neuron. The presynaptic neuron fires one action potential and releases neurotransmitter into the synapse, yet it is not strong enough to generate an action potential in the postsynaptic neuron. But, if this presynaptic neuron fires multiple action potentials in a short period of time, the postsynaptic neuron reaches threshold. This process is called --------------.

   	A.	EPSP/IPSP cancellation
   	B.	Temporal summation
   	C.	Chronicle summation
   	D.	Spatial summation
   	E.	Tonical summation

Answer 1

ANSWER :

1. The dendrites of a neuron gather information (from other neurons or from the environment) and turn it into a localized electrical signal called graded potentials.

2. Sensory neurons are also known as afferent neurons and relay information toward the CNS. Whereas motor neurons are also known as effector neurons and relay information away from the CNS toward the effector tissue.

3. The myelin sheath present over the length of axon (except Ranvier's node), and functions to increase the transmission speed of action potentials, and also provide protection via insulating the nerve fibres.

4. The integrative function of nervous system includes the integration, analysis, and storing the information. The motor function of nervous system elicits proper response toward a stimuli, while sensory functions of nervous system includes detection of external and internal stimuli via specific afferent nerve fibres. Hence options (A), (B), & (E) are the correct answer choices.