Topic 3- Biopsychology

Question 1

What is a neuron and what are the three main types of neuron

Answer 1

A neuron is a nerve cell which transfers
information between different parts of the brain.

Thee three main
types of neurons:

1. sensory
2. motor
3. relay.

Question 2

How do they work together?

Answer 2

Sensory neurons
are taking the excitation of a sense organ (an affector) and passing
an electrical current down its axon to where a synapse occurs at
the terminal of the axon.

A relay neuron passes an electrical
stimulus of one neuron to another neuron via a synapse.

A motor
neuron takes this electrical stimulus back along its axon to an
effecter organ such as a muscle to bring about an action (an effect).

Question 3

Can you draw and label each neuron?

Answer 3

Motor have:

Dendrite, Cell body, Axon, Myelin Sheath, Neurofibril Node

Relay have:

Presypnatic Terminal, Dendrite, Cell body, Axon

Sensory Neuron:

Myelin Sheath, Cell body, Axon, Receptor Cell

https://ebooks.boost-learning.co.uk/wr/viewer.html#book/1a8afd8e-673d-4d4a-8b7b-32e0163aed1e/ch05/pos_46.93705451259914

Question 4

What is the synapse and how are neurotransmitters produced?

Answer 4

There are gaps
between neurones, which are called synapses, and chemicals called
neurotransmitters are produced by the presynaptic neurones
which diffuse across to the post-synaptic neurones.

Question 5

Can you draw a diagram of the synapse?

Answer 5

Use words such as synaptic cleft, synaptic vesicle, Receptor, Terminal, Transporter, Neurotransmitter, Postsynaptic Neuron,

Question 6

What are the 5 steps in synatic transmission?

Answer 6

1. An electrical nerve impulse travels along the axonof the first neuron, the presynaptic neuron.
2. When the nerve impulse reaches the dendrites at the end of the axon, chemical messengers called
   neurotransmitters
   are released.
3. These chemicals
   diffuse across the synaptic cleft.
4. The chemicals bind with receptor molecules on the membrane of the second neuron (postsynaptic neuron).
   The receptor molecules on the second neuron can only bind to the specific neurotransmitters released from the first neuron.
5. The binding of neurotransmitter to the receptors stimulates the second neuron to transmit an electrical impulse along its axon. The signal therefore has been carried from one neuron to the next.

Question 7

What is the process of synaptic transmission for?

Answer 7

It is the process for transmitting messages from neuron to neuron

Question 8

What speed does this occur at?

Answer 8

High speed

Question 9

What are the 5 steps that cause excitation/ inhibition to happen?

Answer 9

1. Not all messages prompt activation in the same way. It depends on the action potential’ of the post-synaptic neuron and the message type received.
2. Only certain neurotransmitters can ‘unlock’ a message channel in certain receptors in the post-synaptic neuron. Think of it is a lock and key method.
3. When the right neurotransmitter) meets the right lock (receptor) a specific ion channel in the membrane is opened up, a bit like a door.
4. Ions then flow through the membrane into the neuron along their specific pathways.
5. This flooding of ions can cause a ‘potential’ in the dendrites. These potentials can be excitatory or inhibitory.

Question 10

What is the difference between excitatory and inhibitory potentials?

Answer 10

Excitatory potentials make it more likely for the neuron to fire and so, if a synapse is more likely to cause the post-synaptic neuron to fire so, it is called an excitatory synapse.

Inhibitory potentials make it less likely to fire and, if the message is likely to be stopped at the post-synaptic neuron, it is called an inhibitory synapse.

A good analogy to understand the role of excitation and inhibition is the pedals of a car. An excitatory potential is like the accelerator and an inhibitory potential is like the brake.