Neurophysiology

Question 1

PNS - Peripheral nervous system

Answer 1

Nervous system outside the brain and spinal cord.

In the pns, Schwann cells produce this insulating coating.

Question 2

CNS - Central nervous system

Answer 2

Complex of nerve tissue that controls activities of the body. Vertebrates comprises the brain and spinal cord.

Question 3

Nervous system function

Answer 3

@ cellular network, single cells or even subcellular compartments.
Generation and propagation of electrical impulses within and between neurons.

Question 4

Process

Answer 4

Involves for those that have disorders affecting the NS including Parkinson’s, MS multiple sclerosis, motor neurone disease, viral encephalitis meningitis, stroke or are suffering w/ dementia.

Question 5

Dentrite

Answer 5

Direct impulse to cell body.

Carry info into cell body which contains the nucleus and other associated organelles of cells.

Question 6

Axon

Answer 6

Single extension from cell body.

Conducts impulses away from cell body or soma

Question 7

Synaptic knob

Answer 7

Swollen end of axon.

When electrical impulse arrives @ synaptic knob, neurotransmitters is released into the synaptic cleft.

Question 8

Axon hillock

Answer 8

Connects soma to axon.
Extends or drawn out to from the axon.
Cell body narrows @ part called Axon hillock

Question 9

sensory receptor

Answer 9

Detects changes in environment

Question 10

CNS - central nervous system

Answer 10

Brain and spinal cord

Question 11

Nissl bodies

Answer 11

Free and fixed ribosomes.

Question 12

Myelinated internode

Answer 12

Axon region w/ Schwann cell

Question 13

Neurolemma

Answer 13

outer Schwann cell membrane

Question 14

Synaptic vesicles

Answer 14

Vacuole of neurotransmitters

Question 15

Perikaryon

Answer 15

Surrounds the nucleus and contains groups of free and fixed ribosomes called nissl bodies

Question 16

Telodendria

Answer 16

Axon divide into collateral branches. If the collateral breaches subdivide even more these are known as telodendria.
Each telodendrum ens in synaptic knob.

Question 17

Neurotransmitters

Answer 17

found in the neuron stored in the synaptic vesicles. When an electrical impulse arrives @ synaptic knob, neurotransmitter is released int the synaptic cleft.

Question 18

Axon of neuron

Answer 18

Usually covered by a myelin sheath

Question 19

Gaps in sheath

Answer 19

Gaps in sheath are called nodes of ranvier

Question 20

Axon membrane

Answer 20

Axon membrane aka axolemma

Question 21

Neurilemma

Answer 21

Outerlay of Swann cells covering axolemma @ myelinated internodes

Question 22

Astrocytes

Answer 22

Found @ CNS

Hold neurons in position and forms which aka blood brain barrier.

Question 23

Depolarisation

Answer 23

When the membrane potential becomes less negative - more positive

• change in the cell during which cell undergoes a shift in electric charge distribution, resulting in less negative charge inside cell.
• opening of channels that let positive ions to flow into the cell causing depolarisation
• AP has changed the membrane potential to +ve value.
• cell reaches its highest voltage from depolarisation.

Question 24

Latent period

Answer 24

Time interval - resting period of neuron

Question 25

Stimulus

Answer 25

Event that evokes specific functional reaction in organ or tissu

Question 26

Repolarisation

Answer 26

Change in the membrane potential that returns to a negative value just after depolarisation

Question 27

Glial cells

Answer 27

Physical support for neurons

- provide nutrients and regulate extracellulur fluid of brain especially surounding neurons and their synapses

Question 28

Influx

Answer 28

Flow inward or into something

Question 29

Hyperpolarisation

Answer 29

Change in cells membrane potential that make it more negative - inhibits AP by increasing stimulus required to move membrane potential to AP threshold.

Question 30

Action potential

Answer 30

Impulse occurs when you’re on a stimulated above its resting potential