Chapter 3 Midterm 1

Question 1

What Camillo golgi do?

Answer 1

Stained brain tissue and determined brain worked through a nerve net with info flowing around it

Question 2

What did santiago Ramon y Cajal do?

Answer 2

studied small chicks brain tissue, said it’s made of discrete cells that get complicated as you grow, came up with the nuron hypothesis- more neurons is more ocmplex behaviour

Question 3

What are the parts of a neuron?

Answer 3

dendrites, cell body (soma)- contains nucelus, goes down to axon hillock, then axon, then branches off into axon collateral, telodenria and terminal button

Question 4

How does information flow through a neuron?

Answer 4

info from neurons is collected at dendrites, is then processed in the cell body and then passed to axon which channels info into single message and then to the terminal where it is passed on to its target

Question 5

What do neurons accomplish through this passing of info?

Answer 5

regulate body processes: such as breathing, heartbeat, temp
regulate cognitive processes: such as learning, decision making, thougths

Question 6

What are neural networks?

Answer 6

Functional groups of neurons that connect wide areas of the brain and spinal cord

Question 7

What are the three kinds of neurons? Desccribe em

Answer 7

sensory neurons- bring info to CNS/spinal cord from sensory recpetors in or on body- can have a bipolar neuron (one dendrite, one axon) or a somatosensory neuron (has soma face one way)
Interneurons- link up sensory and motor neurons within the CNS, can have association cells (goes from thalamus to CNS), pyramidal cells (goes from cortex to brain and spinal cord), and Pukinje cell (carries info from cerebellum to rest of the brain and spinal cord)
Motor neurons- send signals from brain and spinal cord to muscles, have big dendritic networks, large cell bodies and large axons that connect to muscles- all efferent info must pass through them.

Question 8

Describe slide 11

Answer 8

Robot orientsitself towards crcket with just exciartory wires, when having inhibotory only goes towards cricket when it’s dark

Question 9

How do neurons determine if they will be active or not?

Answer 9

By summing all the signals they get, if more ecxcitatory they go if more inhibitory they stop.

Question 10

What are glial cells?

Answer 10

help neurons transmit info by binding them together and providing nutrients, support, and protection

Question 11

What are the four types of glial cells? Describe them

Answer 11

Ependymal cell- secretes CSF
astrocyte- forms blood brain barrier, heals scarring, gives nutrients, support, and repair. Contributes to info transfer
Microglial cell- Small, derived from blood, removes dead tissue, migrate into brain
Oligodendroglial cell- forms myelin around CNS axons in the brain and spinal cord
Schwann cell- wraps around peripheral nerves to form myelin

Question 12

Errors in glial cell production causes what?

Answer 12

tumours

Question 13

What is the blood brain barrier?

Answer 13

astrocytyes (star shaped glia) has extension that attach to blood vessels and the brains lining, binds blood vessels together preventing substances from entering brain through blood vessel walls

Question 14

What is myelin?

Answer 14

formed by schwann and oligodendroglial cells- helps neurons by acting as insulin of “wires” stopping them from short circuting and sends info fast

Question 15

How is multiple scelrosis caused?

Answer 15

loss of myelin in the CNS

Question 16

When does paralysis occur?

Answer 16

Occurs during severing of motor neuron axons and sensory fibers- causing loss of sensation and movement

Question 17

How do people recover from paralysis?

Answer 17

microglia and schwann cells help repair axons in the PNS

Question 18

In the CNS does axon repair take place?

Answer 18

No, repair of axons does not take place, oligodendroglial cells provide myselin wrapping

Question 19

How do schwann cells help during paralysis? microglia cells?

Answer 19

schwann cells shrink and divide across dead axon, forms glial cells along the former axons path, the neuron sends out axon sprouts, one finds the schwann cell path and the schwann cells cover it in new myelin forming a new axon.
microglia take the damaged brain cells, engulf it and remove via phagocytosis

Question 20

How are our chromosomes organized?

Answer 20

23 pairs, 1-22 autosomes, 23 sex chromosomes

Question 21

What does penetrance mean, use an example?

Answer 21

penetrance is the word used to describe the degree to which a genotype leads to a phenotype, ex: hunintongs has almost 100% oenetrance, will go to kid if parents have it

Question 22

What is epigenetics?

Answer 22

describes how a single code produces a different cell types, but a genome can code for many phenotypes through environmental modification

Question 23

Why does canada have high rate of parkinsons?

Answer 23

Because of chemicals put in soil and water supply, farmers have it the worst as they’re close to it.

Question 24

How does the brain work?

Answer 24

Materialistically
Anatomically and Functionally
Cellularly (Genetically and Epigenetically