Neurons

Question 1

What is the nucleus of the neuron and where is it located?

Answer 1

• Nucleus is powerhouse of cell

- It is located in cell body

Question 2

What is the cell body and where is it located?

Answer 2

• Keeps nucleus and organelles inside

- Surrounds nucleus and typically has dendrites around it (in motor neuron)

Question 3

What are dendrites and where are they located?

Answer 3

• Typically branch out from cell body in motor neuron
• Thin, short fibers
• Specialised to receive information

Question 4

What is the axon and where is it found?

Answer 4

• Branches out (down for motor neuron) and is usually btwn. dendrites & axon terminals
• Long, thin tube filled w/ fluid which transmits messages to axon terminals

Question 5

What is the myelin sheath and where is it located?

Answer 5

• Fatty tissue that covers axon in segments

- 20 times faster communication if neuron is myelinated

Question 6

What are the axon terminals and where are they located?

Answer 6

• At the end of axon
• Contains small sacs storing neurotransmitters
• Message is distributed from neurotransmitters at axon terminals

Question 7

What are the different types of neurons?

Answer 7

1. Motor neuron - most commonly drawn one and only one required to label in exam
2. Sensory neuron
3. Interneuron

Question 8

What is the role of a motor neuron?

Answer 8

• Send messages from CNS to muscles, glands & organs

- Responsible for movement

Question 9

What is the role of an interneuron?

Answer 9

• Can only be found in CNS

- Responsible for processing info. btwn. sensory & motor neurons

Question 10

What is the role of a sensory neuron?

Answer 10

• Neurons activated by sensory input from environ.

- Aids in reflexes

Question 11

How do neurons transmit information to each other?

Answer 11

• Once electrical message reaches axon terminal, chem process occurs
• Chemicals released from synaptic knob of neurons are called neurotransmitters
• Synapse = small gap btwn. two neurons where neurotransmitters are released

Question 12

What is a neurotransmitter?

Answer 12

• Chemical created by neuron
• Each neurotransmitter has a particular shape which binds to a specific receptor site
• This is called lock and key model

Question 13

What are some important neurotransmitters?

Answer 13

• Serotonin
• Cortisol
• Dopamine
• Oxytocin

Question 14

What is serotonin’s role in the body?

Answer 14

• Neurons that use it are only located in brain
• Involved in mood and onset of sleep
• Contributor to anxiety & depression

Question 15

What is dopamine’s role in the body?

Answer 15

• Neurons that use it are located in brain
• Involved in emotional response
• Plays role in pleasure and reward

Question 16

What is oxytocin’s role in the body?

Answer 16

• Produced in brain

- Contributor to anxiety & depression