PSY 1101 - Chapter 03: Biology & Neuroscience (Pt. 1)

Question 1

What are the two main divisions of the Nervous System?

Answer 1

• Central nervous system: Brain & spinal cord
• Peripheral nervous system: All the nerves in the body outside of the central nervous system

Question 2

What is the Nervous system?

Answer 2

A communication network that receives information from the external world as well as from within your body to then analyze, organize, and interpret it in a meaningful way

Question 3

Where is the information received from the nervous system sent to?

Answer 3

Information is sent to muscles and glands to induce a desirable behaviour

• conscious experiences are created along the way by the NS

Question 4

What are the Cells of the NS?

Answer 4

• Neurons
• Glial Cells

Question 5

What are Neurons?

Answer 5

• The basic communication unit in the nervous system
• The communication between the neurons are an electrochemical process

Question 6

What are Glial Cells?

Question 7

What is an Action Potential?

Answer 7

The communication of neurons is an electrochemical that creates an electrical / neural impulse known as an action potential.

• Leads to the release of neurotransmitters

Question 8

What are Neurotransmitters?

Answer 8

Chemicals that neurons use to send messages to other neurons

Question 9

What is the Basic Structure of Neurons?

Answer 9

Neurons come in many shapes and sizes but they have the same basic structure

• Cell body (soma)
• Dendrites
• Axon
• Axon branches / terminals
• Terminal Buttons
• Myelin Sheath

Question 10

What are Cell Bodies of Neurons?

Answer 10

the nucleus that contains the DNA inside the soma (manufacture everything that the neuron does to survive and thrive)

Question 11

What are Dendrites?

Answer 11

Dendrites are going to increase the surface area of the soma without taking up much space
- Receives messages from other neurons

*Think of them as antennas because they receive messages from neurons.

Question 12

What are Axons?

Answer 12

when a neuron fires, the action potential is going to propagate (travel) down the axon
- the action potential is going to propagate until it reaches the terminal buttons

Question 13

What are Terminal Buttons?

Answer 13

• little nobs at the end of axon branches
• They contain the neurotransmitters
• when the action potential reaches the terminal button they are gonna release the neurotransmitters

Question 14

What is a Myelin Sheath?

Answer 14

• some axons are covered with myelin sheath
• Its a white fatty like substance that provides insulation for the axons
• Axons covered by the myelin sheath transfert information faster than those not covered by it (speeds up the transfer of the information)

Question 15

What is Multiple Sclerosis?

Answer 15

The destruction of the myelin sheath

Question 16

What is a Synapse?

Answer 16

Area where neurons meet to communicate

Question 17

What is a Synaptic Cleft?

Answer 17

A very tiny space between two neurons at the synapse

Question 18

What is the Pre and Post Synaptic Neuron?

Answer 18

• Presynaptic neuron is the neuron that sends out messages
• Presynaptic neuron is the neuron that sends out messages

Question 19

What are Glial Cells?

Answer 19

For the longest time people thought the glial cells were the nannies of the neurons. They are called th nannies because they take care of the neurons

Question 20

Why are Glial Cells considered the Nannies of Neuron cells?

Answer 20

They help neurons:
- develop
- nutrition
- protection
- Clean after them
- Remove dead neurons

Question 21

What else are Glial Cells involved in?

Answer 21

involved in higher mental functioning such as learning memory possibly intelligence; they seem to be linked and associated with brain diseases including mental illness

Question 22

What are Oligodendrocytes and Schwan Cells?

Answer 22

Oligodendrocytes and Schwan cells are both involved in the production, laying down, and repair of the myelin sheath

Question 23

Where do Oligodendrocytes and Schwann Cells function?

Question 24

What are Microglia?

Answer 24

Play a role in learning and memory: degeneration linked with Alzheimer’s disease
- Immune function

Question 25

what other types of glia cells share in the immune duties of the microglia?

Question 26

What are xxx linked to?

Question 27

What disease is xxx linked to?

Question 28

What type of disease is xxx linked to?

Question 29

one more linked to?

Question 30

What is 80% of our brain comprised of?

Answer 30

Our brain is 80% water and this water has dissolved chemicals in it

Question 31

How do the concentrations of ions compare in the Intra versus Extracellular fluid?

Answer 31

Intracellular Fluid (inside the neuron -): higher concentration of negative ions

Extracellular Fluid (outside the neuron +): higher concentration of positive ions

Question 32

What is the Electrical Charge at rest?

Answer 32

-70mV

Question 33

What are the Dissolved Chemicals found in the ICF and ECF?

Answer 33

Sodium, chloride, and potassium ions.

• These ions are found in different concentrations inside and outside of the neurons
• Concentrations are going to change depending on what’s going on with the neuron

Question 34

What happens to the Neuron when it is at Rest?

Answer 34

Inside: higher concentration of negative ions; negatively charged

Outside: high concentration of positive ions; positively charged

• Electrical charge is -70mV
• membrane is polarized
• Neurons are constantly receiving messages when not communicating
• Even at rest, neuron is constantly receiving messages

Question 35

What are the Two Types of Messages?

Answer 35

1. Inhibitory
2. Excitatory

Question 36

What are Inhibitory Messages?

Answer 36

Instruct the neuron not to fire (not to communicate)
- These messages are going to change the concentration of ions
- Change in concentration in such a way that the inside is more negative (from -70mV to -77mV)
- Neuron is less likely to fire
- The membrane is said to be hyperpolarized

Question 37

What are Excitatory Messages?

Answer 37

Instruct the neuron to fire (to communicate)
- These messages are going to change the concentration of ions in such a way that the inside becomes less negative
- Change in concentration in such a way that the inside is less negative (from -70mV to -63mV)
- Neuron is more likely to fire
- The membrane is said to be depolarized

Question 38

What is the Threshold of Excitation?

Answer 38

When the electrical value inside of the ion is -50 mV we call this the threshold of excitation