Lecture 2B:

Question 1

Neurons

Answer 1

Cells in the nervous system that communicate with one another to perform information-processing tasks

Question 2

Glia

Answer 2

Cells that support the functionality of neurones by providing physical support, suppling nutrients and enhancing neuronal communication

Question 3

Soma

Answer 3

The cell body of a neuron, which contains the nucleus, coordinates information-processing tasks and keeps the cell alive

Question 4

Dendrite

Answer 4

A branched treelike structure attached to the soma of a neuron; it receives information from other neurones and relays it to the cell body

Question 5

Axon

Answer 5

A long thin cylindrical structure that transmits information from the soma of a neuron to its terminal button

Question 6

Terminal button

Answer 6

The bud at the end of a branch of an axon; forms synapses with another neuron; sends information to that neuron

Question 7

Synapse

Answer 7

The junction or region between the terminal button of an axon and the membrane of another neuron

Question 8

Neurotransmitter

Answer 8

A chemical that is released by a terminal button; can have an excitatory or inhibitory effect on another neuron. Transmit information across the synapse to a receiving neuron’s dendrites

Question 9

Receptors

Answer 9

Parts of the cell membrane that receive neurotransmitters and initiate a new electric signal

Question 10

Myelin sheath (2)

Answer 10

• A sheath that surrounds axons and insulates them, preventing messages/signals from ‘spreading’ between adjacent axons
• Layer of fatty material made up of glial cells

Question 11

Nodes of Ranvier

Answer 11

A naked portion of a myelinated axon, between adjacent glial cells - also helps to speed up conduction

Question 12

Resting potential

Answer 12

The difference in electric charge between the inside and outside of a neuron’s cell membrane

Question 13

Action potential

Answer 13

An electric signal that is conducted along the length of a neuron’s axon to a synapse

Question 14

Refractory period

Answer 14

The time following an action potential during which a new action potential cannot be initiated

Question 15

Excitatory transmitters (3)

Answer 15

• Cause depolarisation
• Neuron becomes more positive (less negative inside)
• Increases the likelihood of an action potential

Question 16

Inhibitory transmitterts (3)

Answer 16

• Cause hyperpolarisation
• Neuron becomes more negative
• Decreases the likelihood of can action potential