Exp 3: Neurophysiology of Nerve Impulses Flashcards Preview

BMS 302 Exam 1 > Exp 3: Neurophysiology of Nerve Impulses > Flashcards

Flashcards in Exp 3: Neurophysiology of Nerve Impulses Deck (53)
Loading flashcards...
0

Under resting conditions potassium ions move ___ the neuron through ____ channels.

out of; leakage

1

Match the following parts of the neuron and their function.
A) Dendrites
B) Soma (cell body)
C) Axon

-input area; receives signals from other neurons
-input area; main nutritional and metabolic area
-conductive region: generates an action potential

A) input area; receives signals from other neurons
B) input area; main nutritional and metabolic area
C) conductive region: generates an action potential

2

Acetylcholine (ACh) and GABA are neurotransmitters that open chemically-gated channels. What ions pass into the cell when theses channels are activated?
Ach
GABA

A) sodium
B) chloride

A) sodium
B) chloride

3

Nongated channels contribute to the development of ______, while chemically gated channels in important in the development of _______, and voltage gated channels are responsible for _______.

resting membrane potentials; graded potentials; action potentials

4

The difference in the concentration of a particular solute between two adjacent area; provides the chemical force that causes ions to move:

Concentration gradient

5

The electrical force across a cell membrane that results from the separation of charge across that membrance; also called the membrane potential:

Electrical potential

6

The combined electrical and chemical forces on an ion; determine the net movement of that ion:

Electrochemical gradient

7

In the resting cell, the "force" that pushes K+ out of the cell is ______, while the "force" that tends to pull K+ back into the cell is ______.

chemical; electrical

8

When the chemical and electrical forces are equal and opposite in a cell permeable only to K+, this is called the _______ potential for K+ which is _____ mV.

equilibrium; -90

9

The action potential changes the membrane potential from [x] mV (resting) to [y] mV and back again to the resting membrane potential. This is the result of a change in membrane permeability first to [z] ions then to [a] ions due to the opening of [b] gated channels.

X) -70 mV
Y) +30 mV
Z) sodium
A) potassium
B) voltage

10

If the membrane potential becomes more negative than -70 mV (resting), it is known as:

hyperpolarization

11

Following an action potential, the neuron cannot generate another action potential because _____ channels are inactivated. This period is known as the ______ refractory period.

Na+ ; absolute

12

During the _____ period, the cell can generate another action potential, but only if the threshold stimulus is _____ than the normal stimulus strength.

relative refractory period; greater

13

The binding of ACh opens channels in the dendrites or cell body that permits both Na+ and K+ to move through them. ____ move into the cell, while ____ move out. _____has the greatest electrochemical gradient and therefore the net movement of these two ions causes the membrane potential to become ______ negative.

Na+; K+; Na+; less

14

____ move into the cell during an inhibitory postsynaptic potential (IPSP) and result in the membrane potential becoming _____ negative.

Cl-; more

15

Somatic Nervous System

One motor neuron originating in the CNS and synapsing on the effector.

16

Parasympathetic Nervous System

A long pre-ganglionic neuron synapsing on a short post-ganglionic neuron that in turn synapses on the effector.

17

Sympathetic Nervous System

A short pre-ganglionic neuron synapsing on a long post-ganglionic neuron that in turn synapses on the effector.

18

Somatic Nervous System

Releases acetylcholine that binds to nicotinic receptors on the effector.

19

Parasympathetic Nervous System

Releases acetylcholine that binds to muscarinic receptors on the effector.

20

Sympathetic Nervous System

Releases norepinephrine that binds to adrenergic receptors on the effector.

21

Applies to both the Parasympathetic and Sympathetic branches of the Autonomic Nervous System

Releases acetylcholine from pre-ganglionic neurons that binds to nicotinic receptors on the post-ganglionic neuron.

22

Applies to both the Parasympathetic and Sympathetic branches of the Autonomic Nervous System

Effectors are smooth muscle, cardiac muscle, and glands.

23

Somatic Nervous System

Effectors are skeletal muscles.

24

Sympathetic Nervous System

Has a chain of ganglia along the spinal cord.

25

Norepinephrine may be excitatory or inhibitory in the perpheral nervous system. Its action depends on the receptor to which it binds. Match each of the Ne receptors discussed in this unit with its appropriate response.

Alpha
Beta 1
Beta 2

alpha1
Correct A. Norepinephrine binds to this receptor type and constricts (by increasing contraction of smooth muscles) the blood vessels to the skin.

beta1
Correct B. Norepinephrine binds to this receptor type and increases heart rate and contractility.

beta2
Correct C. Norepinephrine binds to this receptor type and causes bronchodilation (by decreasing contraction of smooth muscles) in the bronchioles of the lungs.

26

True or False: The amplitude of synaptic potentials varies with the amount of neurotransmitter binding to receptors on chemically gated channels.

True

27

True or False: Reaching threshold requires more than one synaptic potential.

True

28

True or False: Synaptic potentials can be excitatory or inhibitory.

True

29

Establishing the ion gradients (sodium and potassium) responsible for the resting membrane potential requires energy through the use of the _______.

sodium-potassium pump