Neurons and neurotransmitters

Question 1

What does the cell body of a neuron do?

Answer 1

It contains the nucleus and is connected to the dendrites. Most important role is manufacturing new cell components

Question 3

Which part of the neutron receives the electrical messages from other neurons?

Answer 3

Dendrites

Question 4

What is the myelin sheath?

Answer 4

A protective covering over the axon. Speeds up synaptic transmission.

The sheath contains gaps along the axon called nodes. The neural signal jumps from node to node and this is how transmission is sped up

Question 5

What is an axons role in a neutron?

Answer 5

Conducts the electrical impulses from the cell body to send to other neurons as a message

Question 6

Explain resting potential.

Answer 6

The resting state involves an imbalance in charge across the cell membrane. Inside is more negative than outside

Question 7

Explain graded potential

Answer 7

Are electrical charged caused by signals from other neurons. Can be either excitatory or inhibitory.

Question 8

What is an excitatory graded potential?

Answer 8

Depolarisation.
Membrane potential becomes more positive. This makes it closer to the firing threshold which makes the neuron more likely to fire!!

Question 9

What is an inhibitory graded potential?

Answer 9

Hyperpolarisation.
Membrane potential becomes more negative and moves further away from the threshold which makes the neuron less likely to fire.

Question 10

Glial cells

Answer 10

Surround neurons and provide support and insulation between them

Question 11

What is the synapse?

Answer 11

The synapse is the fluid filled gap between the neurons that the neurotransmitters travel through.

Question 12

What does pre and post synaptic mean?

Answer 12

Refers to the positioning before or after the synapse

Question 13

Describe the process of synaptic transmission

Answer 13

• Vesicles inside the axon containing neurotransmitters
• the vesicles fuse with the membrane and the neurotransmitters cross the synapse
• the neurotransmitters attach to the dendrites and produce a graded potential

Question 14

What happens after the synaptic transmission?

Answer 14

The transmitter is then inactive and released from the receptor site. It will then either make its way back to the pre-synaptic cell (re-uptake) or be broken down by enzymes.

Question 15

How does the lock and key model fit into the nervous system?

Answer 15

The lock and key model describes how the post-synaptic receptor sites are very specific and only specific neurotransmitters are accepted into the site

Question 16

What is glutamate?

Answer 16

Main excitatory transmitter.

Involved in learning, memory and transfer of sensory input

Question 17

What is GABA?

Answer 17

The main inhibitory transmitter.

Dampens neural activity - involved in learning, memory and sleep

Question 18

What kind of drugs increase the activity of GABA?

Answer 18

Anti-anxiety.

Used to suppress overactive brain roles linked to worry.

Question 19

What is acetylcholine (ACh)?

Answer 19

Muscle contractions

Question 20

What is dopamine?

Answer 20

Involved in motor function and reward.

Question 21

What is serotonin?

Answer 21

Involved in cortical arousal, mood, sleeping, eating.

Question 22

What is noradrenaline?

Answer 22

Mobilises the brain and body for arousal

Involved in cortical arousal and autonomic nervous system activity

Question 23

What is anandamide?

Answer 23

A fatty acid neurotransmitter

Associated with pain control, memory, learning and emotions

Question 24

What are endorphins?

Answer 24

Involved in main control and mood elevation

Question 25

What happens when someone has high levels of dopamine?

Answer 25

Schizophrenia

Question 26

What happens when someone has low amounts of dopamine?

Answer 26

Parkinson’s disease

Question 27

What is a psychoactive drug?

What are the 2 different types and how do they work?

Answer 27

Drug that interacts with the neurotransmitter system and affects mood, arousal and behaviour.

Agonists: (enhances receptor site activity)
Antagonists: (decrease receptor site activity)

Question 28

What does SSRI stand for? And what do they do?

Answer 28

Selective serotonin uptake inhibitors

Used to treat depression as increases serotonin uptake

Question 29

The nervous system can be divided into…..

Answer 29

The peripheral and central nervous systems

Question 30

What is the central nervous system?

Answer 30

Involves the spinal cord and the brain

Question 31

What role does the spinal cord play?

Answer 31

Receives sensory input and sends this info to the brain - also responds to motor output

Question 32

What role does the brain play?

Answer 32

directs psychological activity, processes information and maintains life supports

Question 33

What does the peripheral nervous system consist of?

Answer 33

The somatic nervous system and the autonomic nervous system

Question 34

What is the somatic nervous system?

Answer 34

Voluntary control of muscle movements via skeletal muscles

Question 35

What does the autonomic nervous system do and what does it consist of?

Answer 35

sends and receives information to and from the glands and organs of the body – involuntary. Things you can’t control eg. hormone release.

Consists of the sympathetic and parasympathetic nervous systems

Question 36

What does the sympathetic nervous system do?

Answer 36

General arousal and responding to threats

Fight or flight

Question 37

How do the parasympathetic and sympathetic systems work together?

Answer 37

Detection of a threat results in a stimulation of the peripheral organ and musculature response (increased breathing and heart rate, digestion/salivation inhibited, pupil dilation, bladder/bowel relaxation, hair standing erect)

Response: threat is appropriately responded to (flight or fight or our perception changes)

Activation of the parasympathetic branch – restores normal levels of function.
- Parasympathetic nervous system – routine maintenance of energy resources (rest and digest) and decreasing arousal

Question 38

What does the parasympathetic nervous system do?

Answer 38

Calms the body down and maintains energy

Rest and digest

Question 39

Explain the endocrine system

Answer 39

The endocrine system is a system of glands that control vital functions (eg. growth, metabolism, reproduction). Hormones are chemicals that are released into the blood stream by this system that influence some organs. They bind to cell receptor sites in the body which is similar to neurotransmitters.

Question 40

What does the hypothalamus do?

Answer 40

Maintains homeostasis

Releases hormones by activating pituitary gland

Question 41

What is the pituitary gland and what does it do?

Answer 41

is a master gland that is under the control of the hypothalamus and releases hormones which have a direct effect or will active glands further down the chain.

Question 42

What is oxytocin?

Answer 42

the love molecule involved in birth contractions, milk production and interpersonal trust

Question 43

What are the adrenal glands?

Answer 43

Glands located near the kidneys that release adrenaline and cortisol to trigger or maintain the flight or fight response

Question 44

What does the thyroid gland do?

Answer 44

Releases growth and metabolism hormones

Question 45

What does the pancreas do?

Answer 45

controls blood sugar levels and produces insulin

Question 46

What do gonads do?

Answer 46

release sex hormones (estrogen and testosterone)

Question 47

What is the absolute refractory period?

Answer 47

Time during which another action potential is impossible