Biopsychology: Neurons And Synaptic transmission

Question 1

Neuron

Answer 1

The basic building blocks of the nervous system, the neutrons are nerve cells that process and transmit messages through electrical and chemical signals

Question 2

Types of Neuron

Answer 2

Sensory: carry messages for PNS to CNS, long dendrites and short axons

Relay: connect sensory neurons to the motor neurons or other relay neurons. Short dendrites and snort axons

Motor: connect the CNS to effector such as muscles and glands. Short dendrites and long axons

Question 3

The structure on a neuron

Answer 3

Vary in size from less than a millimetre to up to a meter, but all share the same basic structure. The cell body includes a nucleus, which contains genetic material of the cell. Branch like structures called dendrites, these carry nerve impulses from the brain neurons towards the cell body. The axon carries and pulses away from the cell body down the length of the new on the accent is coming to fatty layer of myeline sheath protects the axon and speed up the electric transmission of the impulse.

The myeline sheath is segmented by gaps called nodes of Ranvier, speeds up the transmission of the impulses by forcing it to to jump across the gaps along the axon. At the end of the axon there are terminal buttons, that communicate with that next neuron in the chain across a gap known the synapse.

Question 4

Electric transmission - the firing of a neuron

Answer 4

A neuron is in a resting state the inside of the cell is negatively charged compared to the outside

When the neuron is activated by a stimulus, the inside of the cell becomes positively charged for s split second causing an action potential to occur. This creates an electric implies that travels down the axon towards the end of the neuron.

Question 5

Chemical transmissions: synapse

Answer 5

Neurons communicate in groups known as “neural networks” each neuron separated by tiny gaps called synapse.

Signals within neurons: electrically
Signals between neurons: chemically

When electrical imploded reached the end of the neuron it triggers the release of the neruotransmitter from tiny sacs called synaptic vesticles

Question 6

Neurotransmitters

Answer 6

Chemicals that diffuse across the synapse to the next neuron in the chain.
It is next taken up the postsynaptic receptor site, the chemical message us converted back into an electrical impulse and the process of transmission begins again in this other neuron.

Each neurotransmitter had a its own molecular structure that’s fits perfectly into a post-synaptic receptor site.

Question 7

Excitation and inhibitation

Answer 7

Either an excitatory or inhibitory effect in neighbouring neuron. Either resulting in a more negatively charged of positively charged and making in more likely to fire