Lecture 3 (DONE)

Question 1

What does the Nervous System consist of?

Answer 1

CNS & PNS

Question 2

What is in the CNS?

Answer 2

Brain and Spinal Cord

Question 3

What is in the PNS?

Answer 3

The rest of the nervous system that is not the brain and spinal cord

Question 4

What are the 2 types of cells in the Nervous System?

Answer 4

Neurons and Glial Cells

Question 5

What do neurons do?

Answer 5

They communicate through electrical signals

Question 6

What do Glial cells do?

Answer 6

Form the myelin sheath and wrap around the axon

Question 7

What are common components to all cells of the body?

Answer 7

Cytoplasm, nucleus, membrane, mitochondria, ribosomes, lysosomes, and golgi complex

Question 8

What is the difference between anabolism and catabolism?

Answer 8

Anabolism USES energy to make something and catabolism breaks down smaller parts to CREATE energy

Question 9

What are two things that make neurons like other cells?

Answer 9

They have a membrane potential and ion channels

Question 10

What is the definition of membrane potential?

Answer 10

Voltage difference inside and outside of cells

Question 11

What do ion channels do?

Answer 11

Allow ions to pass in and out of cell which changes the membrane potential. This is only if the ion channels are OPEN

Question 12

What molecules pass freely through the membrane?

Answer 12

CO2, H20, 02

Question 13

What does it mean when a membrane potential changes?

Answer 13

It is a signal or information

Question 14

What are components that are unique to neurons?

Answer 14

Soma, dendrites, axon, pre-synaptic & post-synaptic terminals, synapse, myelin sheath (glia), and nodes of Ranvier

Question 15

What is another word for soma?

Answer 15

Cell body

Question 16

What do dendrites do?

Answer 16

Receive signals from neurons

Question 17

What axons do?

Answer 17

Send electrical signals from one neuron to the next

Question 18

What is the main function of glial cells?

Answer 18

Support cells and form the myelin sheath.

Question 19

Are all neurons in vertebrates myelinated?

Answer 19

No!

Question 20

In neurons, what does mitosis do?

Answer 20

Make new neurons through mitosis

Question 21

In neurons, what does regeneration of cells mean?

Answer 21

Repair axons that have been cut.

Question 22

Why do neurons in the PNS and CNS lose their ability to undergo mitosis?

Answer 22

in the CNS, there are structures such as the skull and spine that protect the neurons from injury. Do need to expend that much energy to keep regenerating these cells.

Question 23

Do brain cells die as we get older?

Answer 23

No, they just become smaller and less functional.

Question 24

BRAIN CANCER ???

Answer 24

idk come back to it on the slide.

Question 25

Where does regeneration occur in most animals?

Answer 25

In the PNS

Question 26

What is the mechanism for regeneration in the PNS?

Answer 26

There are mechanisms to make collagen around the injury to act as a bridge for neurons to grow along.

Question 27

How does neural communication work?

Answer 27

Electrical signals are sent from one neuron the the next

Question 28

What is the synapse for muscles called?

Answer 28

Neuromuscular junction

Question 29

Does myelination make transmission slower or faster?

Answer 29

Faster

Question 30

Why does pain occur (myelin)?

Answer 30

Unmyelinated neurons

Question 31

Tell the story of how electrical signals travel along a neuron.

Answer 31

1. Neurons have a membrane potential 2. At Rest, nothing happens (-70mV), inside more negative -Conc. difference, K+ inside , Na+ Outside -At rest NOTHING happens 3. Ion channels open

Question 32

How/why do ion channels open?

Answer 32

-NT binds to R on dendrites and opens NT-gated channels selective for NA+ -Na+ rushes into neuron, down the concentration gradient -Membrane potential gets less negative

Question 33

Define depolarization.

Answer 33

Membrane potential becomes less negative.

Question 34

What happens when membrane potential reaches -55mV?

Answer 34

Action potential occurs. Travels down axon all the way to presynaptic terminals as an "electric signal" and changes the membrane potential along the way

Question 35

Define hyperpolarization.

Answer 35

Membrane potential become more negative. Makes it harder to create an action potential

Question 36

Define nodes of ranvier / saltatory conduction.

Answer 36

Gaps between the myelin sheath that speeds up the AP because it can jump over the myelin sheath

Question 37

What goes wrong in MS?

Answer 37

It is where you slowly lose motor control / ability because the myelin gets gets destroyed

Question 38

What is the purpose of the blood brain barrier?

Answer 38

To keep out viruses and bacteria in the CNS

Question 39

How does the blood brain barrier work?

Answer 39

-Endothelial cells line the inside of blood vessels -In all parts EXCEPT the CNS, there are gaps between the endothelial cells so substances in blood can move in and out of blood vessels to body parts -in CNS there are "tight junctions" between cells, which disallow this movement

Question 40

What are some drugs that can get through the blood brain barrier?

Answer 40

Fat soluble substances, ex. cannabinoids. dissolve through fats of blood vessel walls.