Biopsychology- Neurons And Synaptic Transmission (Paper 2)

Question 1

What is the function of sensory neurons?

Answer 1

Carry messages from sense organs (e.g eyes, nose) to the brain to be turned into meaningful information.

Question 2

What is the function of motor neurons?

Answer 2

Carry messages to muscles and glands in order to produce responses.

Question 3

What is the function of relay neurons?

Answer 3

Allow communication between sensory and motor neurons.

Question 4

Describe the characteristics of sensory neurons?

Answer 4

They have long dendrites and short axons.

Question 5

Describe the characteristics of relay neurons.

Answer 5

Short dendrites and short axons.

Question 6

Describe the characteristics of motor neurons?

Answer 6

Short dendrites and long axons.

Question 7

What are dendrites?

Answer 7

They extend from cell body. They carry electrical impulses from other neurons towards the cell body. (Receive messages from body).

Question 8

What is the axon?

Answer 8

Is an extension of the nueron, it carries the impulses away from the cell body to other neurons, muscles or glands.

Question 9

What is sheath of myelin?

Answer 9

It covers the axon of some neurons. A fatty substance. The main purpose of it is to increase the speed at which impulses propagate.

Question 10

What are the main features of a cell body?

Answer 10

• Cell body, Nucleus.
• Dendrites.
• Axons. Axon terminal.
• Myelin sheath.

Question 11

What are Nodes of Ranvier.

Answer 11

The breaks/gaps in the myelin sheath.

Question 12

What is action potential?

Answer 12

Nerve impulses. Electrical signal travelling down the axon.

Question 13

What is a synapse?

Answer 13

The gap between two neurons.

Question 14

What is first stage of synaptic transmission?

Answer 14

• Info is passed down axon of nueron as an electrical impulse known as action potential.
• To reach next nueron it must cross synapse between pre and post synaptic neurons.

Question 15

What does the pre-synaptic neuron contain?

Answer 15

Neurotransmitters.

Question 16

What is second stage of synaptic transmission?

Answer 16

• When the electrical impulse reaches the synaptic vesicles, they release neurotransmitters across the synapse.
• These then bind to receptor sites on post-synaptic sites which become activated

Question 17

What is reuptake?

Answer 17

Any neurotransmitters that have not been absorbed by the receptors will either be destroyed by enzymes in synaptic gap or absorbed by pre-synaptic nueron in process called reuptake.

Question 18

What are the different neurotransmitters?

Answer 18

• Excitatory neurotransmitters (make a neuron more likely to fire).
• Inhibitory neurotransmitters (make it less likely to fire, calm mind).