Chapter 3 #1

Question 0

What is the classic pattern of neural function?

Answer 0

Info flows within a neuron via electrical signals (action potentials) and passes between neurons through chemical signals (neurotransmitters)

Question 1

Neurophysiology

Answer 1

The study of the life processes of neurons

Question 2

Polarized

Answer 2

Exhibits a difference between the electric charge inside and outside of a cell.

Question 3

All living cells are more negative on the inside than the outside. T or F?

Answer 3

True!

Question 4

Ion

Answer 4

Electrically charged molecules contained in a neuron

Question 5

Anions

Answer 5

Negatively charged ions. These are the majority of large protein ions within the cell that can’t exit.

Question 6

Cations

Answer 6

Positively charged ions in a neuron

Question 7

Intracellular fluid

Answer 7

Watery solution inside the neuron where ions are dissolved. Also known as cytoplasm

Question 8

Extra cellular fluid

Answer 8

Fluid in between cells (interstitial fluid) surrounds the cell membrane and contains dissolved ion

Question 9

Cell membrane

Answer 9

The lipid bilateral that ensheathes a cell

Question 10

Microelectrode

Answer 10

Especially small electrode used to record electrical potentials in living cells

Question 11

Resting potential

Answer 11

A difference in electrical potential across the membrane of a nerve cell during an inactive period

Question 12

What is the difference in electrical potentials across a resting neuron’s membrane?

Answer 12

-50 to -80 millivolts (mV)

Question 13

Millivolts (mV)

Answer 13

A thousandth of a volt

Question 14

Ion channel

Answer 14

A pore in the cell membrane that permits the passage of certain ions through the membrane when the channels are open

Question 15

Potassium ion (K+)

Answer 15

A potassium atom that carries a positive charge because it has lost one electron

Question 16

Selective permeability

Answer 16

Property if the membrane to allow some substances to pass through but not others (K+ channels)

Question 17

Diffusion

Answer 17

Tendency of molecules to move from areas of high concentration to lower concentration until a uniform concentration is achieved

Question 18

Electrostatic pressure

Answer 18

The propensity of charged molecules to move, via diffusion, towards areas with the opposite charge.

Question 19

What are the two main forces that drive ions in and out of the neuron?

Answer 19

Diffusion and electrostatic pressure

Question 20

Sodium potassium pumps

Answer 20

Energetically expensive mechanism that pushes sodium ions out of a cell and potassium ions in.

Question 21

What is the ratio at which the sodium potassium pumps each ion?

Answer 21

Three Na+ for every 2 K+

Question 22

Sodium ion (Na+)

Answer 22

A sodium atom that carries a positive charge because it has lost one electron

Question 23

Equilibrium potential

Answer 23

The point at which the movement if ions across the cell membrane is balanced, as the electrostatic pressure pulling ions in one direction is offset by the diffusion force pushing them in the opposite direction

Question 24

The pump and diffusion create a high intracellular concentration of which ion?

Answer 24

K+

Question 25

The pump and diffusion create a high extracellular concentration of which ion?

Answer 25

Na+

Question 26

Hyperpolarization

Answer 26

Increase in membrane potential, the inside of the neuron becomes more negative

Question 27

Depolarization

Answer 27

Brings the membrane potential closer to zero, making the potential of the inside more like the outside

Question 28

What happens when a hyper polarizing stimulus to the membrane?

Answer 28

Passively mirrors the stimulus pulse.

Question 29

Graded response

Answer 29

The greater the stimulus the greater the response

Question 30

Local potential

Answer 30

An electrical potential that is initiated by stimulation at a specific site spreads passively across the membrane and get weaker as they spread away from the point of stimulation

Question 31

Threshold

Answer 31

The stimulus intensity that is just adequate to trigger an action potential at the axon hillock

Question 32

How far must a cell become depolarizer before it reaches the threshold?

Answer 32

Around -40 mV or so

Question 33

Action potential

Answer 33

“Spike”. Rapid reversal of the membrane potential that momentarily makes the inside of he membrane positive with respect to the outside

Question 34

Is the action potential actively or passively reproduced?

Answer 34

Actively

Question 35

All or none property

Answer 35

The amplitude of the action potential is independent to the size of the stimuli. It fires fully or not at all.

Question 36

How does the size of the stimuli effect the action potential?

Answer 36

With stronger stimuli more action potentials are produce but the size is the same

Question 37

After potential

Answer 37

The positive or negative change in membrane potential following an action potential.

Question 38

Knee jerk reflex

Answer 38

Stretching of the tendon beneath the knee leads to an upward kick of the leg

Question 39

Electroencephalogram (EEG)

Answer 39

Records gross electrical activity of the brain via large electrodes placed on the scalp

Question 40

Event related potential/ evoked potential

Answer 40

Averaged EEG recordings measuring brain responses to repeated presentations of a stimulus

Question 41

Epilepsy

Answer 41

A brain disorder marked by major sudden changes in the electrophysiological state of the brain that are referred to as seizures

Question 42

Grand mal seizure

Answer 42

Epileptic seizure in which nerve cells fire in high frequency bursts, usually accompanied by involuntary rhythmic contractions of the body

Question 43

Petit mal seizure

Answer 43

“Absence attack” seizures with spike and wave EEG and involves a loss of awareness and ability to recall surrounding events

Question 44

Complex partial seizures

Answer 44

A type of seizure that doesn’t involve entire brain and can cause a variety of abnormal behaviors

Question 45

Aura

Answer 45

The unusual sensations or premonition that may precede the beginning of an epileptic seizure.