Neurons And Synaaptic Transmission

Question 1

What are neurons

Answer 1

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

Question 2

What is sensory neurons

Answer 2

These carry messages from the PNS to the CNS. They have short dendrotes and axons

Question 3

What are motor neurons

Answer 3

These connect the CNS to effectors such as muscle and glands. They have short dendrites and long axons

Question 4

What are three types of neurons

Answer 4

Sensory
Relay
Motor

Question 5

What does the cell body include

Answer 5

Includes an nucleus which contains the genetic material of the cell

Question 6

Describe what a dendrite is

Answer 6

Branchlike structure dendrite protrude from the cell body. These carry nerve impulses from neighboring neurons towards the cell body

Question 7

What does the axon do

Answer 7

Carries impulses away from the cell body down the length of the neuron

Question 8

What does the myelin sheath do

Answer 8

The axon is covered in myelin sheath that protects the axon and speeds up electrical transmission of the impulse

Question 9

What are nodes of ranvier

Answer 9

If myelin sheath was continuous this would have the reverse effect and slow down the electrical impulse. Myelin sheath is segmented by gaps called Nodes of ranvier. These speed up the transmission of the impulse by forcing it to jump across gaps along the axon

Question 10

What are terminals buttons

Answer 10

Is at the end axon are terminals button that communicate with the next neuron the chain across a gap known as synapse

Question 11

Where is the motor neuron located

Answer 11

Central nervous system but have long axons which form part of the peripheral nervous system

Question 12

Where are the sensory neurons located

Answer 12

Outside CNS, in the CNS cluster known as ganglia

Question 13

Where are relay neurons located

Answer 13

Make up 97% of neurons and most found in brain and the visual system

Question 14

What happens during the electrical transmission

Answer 14

When a neuron is in resting state the inside of the cell is negatively charged compared to the outside. When a neuron is activated by a stimulus the inside of the cell becomes positively charged for a split second causing an action potential to occur. This creates an electrical impulse that travels down the axon towards the end of the neuron

Question 15

What is neural network

Answer 15

Neurons communicate with each other within groups

Question 16

How are signals between neurons transmitted

Answer 16

Chemically across in the synapse

Question 17

How are signals in neurons transmitted

Answer 17

Electrically

Question 18

What happens when the electrical impulse reach the end of the neuron

Answer 18

Triggers the release of neurotransmitters from tiny sacs called synaptic vessels

Question 19

What’s a neurotransmitter

Answer 19

Chemicals that diffuse across the synapse to the next neuron chain the synapse to the next neuron

Question 20

What happens when neurotransmitters crosses the gap

Answer 20

Taken up by a postsynaptic receptor site on the dendrites of the next neuron’s

Question 21

What do axons do to signals

Answer 21

Take signals to synapse

Question 22

What do dendrites take signal to

Answer 22

Takes signals away from

Question 23

What are the chemical message converted to

Answer 23

Chemical message converted back to electrical impulse and process of transmission begins again in this other neuron

Question 24

Where is the neurotransmitter released and received

Answer 24

Released from presynaptic neuron terminal and received by the postsynaptic neuron

Question 25

What affects do neurotransmitters efffect on neighbouring neuron

Answer 25

Excitatory and inhibition

Question 26

What neurotransmitter cause inhibition in receiving neuron

Answer 26

Serotonin and results in the neuron becoming more negatively charged and less likely to fire

Question 27

What hormone/neurotransmitter cause excitation

Answer 27

Adrenaline causes excitation of the postsynaptic neuron by increasing its positive charge and making it more likely to fire

Question 28

What decides whether the postsynaptic neuron is fired

Answer 28

Process of summation