Nerves

Question 1

Sensory Receptors

Answer 1

Specialised cells that detect changes in the environment and act as energy transducers to convert one form of energy into another

Question 2

Sensory Neurone

Answer 2

Neurones which transmit action potentials from receptors to the CNS

Question 3

Motor Neurone

Answer 3

Neurones which transmit action potentials from the CNS to effectors

Question 4

Schwann Cell

Answer 4

Cells which wrap around some neurones to form the myelin sheath

Question 5

Myelinated Neurone

Answer 5

Neurones that are insulated by a myelin sheath and can transmit an action potential more quickly than a non myelinated neurone

Question 6

Node of Ranvier

Answer 6

Narrow gaps in the myelin sheath

Question 7

Resting Potential

Answer 7

The potential difference across a neuronal cell membrane when the neurone is not conducting an action potential – about -70mV inside the cell compared with outside the cell

Question 8

Action Potential

Answer 8

Brief reversal of the resting potential (depolarisation) across the cell surface or a neurone. All action potentials are +40mV

Question 9

Generator Potential

Answer 9

A small depolarisation of the membrane of a receptor cell

Question 10

Saltatory Conduction

Answer 10

“Jumping” of an action potential from one Node of Ranvier to the next Node of Ranvier in a myelinated neurone

Question 11

Neurotransmitter

Answer 11

A chemical released by a presynaptic neurone which diffuses across a synaptic cleft and binds to receptors on the post synaptic neurone membrane

Question 12

Summation

Answer 12

The way in which several small potential changes can produce one large change in potential difference across a neurone membrane