Exam 3

Question 1

The primary structure of a protein can be defined as
a. the final structure of a protein folded in 3 dimensions
b. the complex the protein forms with other subunits
c. the sequence of nucleotides in the DNA
d. the sequence of amino acids in the polypeptide

Answer 1

d. the sequence of amino acids in the polypeptide

Question 2

Amyloid Beta Plaques result from
a. prion induced misfolding of APP
b. protease cleavage of APP then beta fragment aggregation
c. inappropriate ubiquitin targeted degradation of APP
d. gamma secretase targeting of a-synuclein

Answer 2

b. protease cleavage of APP then beta fragment aggregation

Question 3

Post mortem diagnosis of Parkinson’s requires identification of
a. amyloid plaques
b. necrosis
c. lewey bodies
d. huntingtin mutation

Answer 3

c. Lewey bodies

Question 4

Parkinsons disease deficits are largely limited to
a. reactive movements
b. volitional movements
c. involuntary reactions
d. reflexes

Answer 4

b. volitional movements

Question 5

Huntingtin’s disease results from
a. mutation of ubiquitin gene
b. mutation of the gene for huntingtin
c. mutation of the gene for the CAG protein complex
d. none of the above

Answer 5

b. mutation of the gene for Huntingtin

Question 6

Alzheimer’s disease is characterized by
a. lewey bodies
b. Tau neurofibrillary tangles
c. spongiform holes in the brain
d. prion induced protein misfolding

Answer 6

b. tau neurofibrillary tangles

Question 7

Successful pharmacological clearance of amyloid plaques in Alzheimer’s sufferers resulted in
a. clearance or resolution of symptoms
b. acceleration of symptoms
c. remission of symptoms
d. not effect on symptoms

Answer 7

d. not effect symptoms

Question 8

What makes Kuru unique as a human prion disease
a. it doesn’t involve the prion protein
b. it was primarily transmitted through cannabilism
c. it is genetically transmitted
d. it only affects cows

Answer 8

b. it was primarily transmitted through cannabilism

Question 9

The infectious agent in prion diseases is
a. a virus
b. a normal protein
c. a misfolded protein
d. cow brains

Answer 9

c. a misfolded protein

Question 10

What is the role of genetics in prion diseases
a. it is a genetic disorder where a mutation is responsible for all cases
b. there is no role, it is a transmissible diseases that requires a pathogen
c. there is a complex interplay between genetics and environment
d. none of these

Answer 10

c. There is a complex interplay between genetics and environment

Question 11

The difference between PrP^c and PrP^sc is
a. the amino acid sequence
b. the number of CAG repeats
c. the conformation of the protein
d. fatal familial insomnia results from one and Creutzfeldt-Jakob disease results from the other

Answer 11

c. the conformation of the protein

Question 12

What is a protein secondary structure
a. beta loop
b. alpha helix
c. pore loop motif
d. none of the above

Answer 12

b. alpha helix

Question 13

Protein folding occurs as a progressive process. Which are protein that aid in this process as the folding protein is produced
a. telomerases
b. chaperone proteins
c. bell hoop proteins
d. valet proteins
e. Tau

Answer 13

b. chaperone proteins

Question 14

Ubiquitin is a common protein that may play a role in a couple of the neurodegenerative disorders. The basic role of ubiquitin is
a. to activate gene transcription
b. to target proteins for degradation
c. to target proteins to the nucleus
d. to block gene transcription

Answer 14

b. to target proteins for degradation

Question 15

Excitation in a neuron caused by the release of inhibition is called
a. excitation
b. disinhibition
c. inhibition
d. disexcitation

Answer 15

b. disinhibition

Question 16

A) Cortex > B) Caudate > C) Globus Pallidus (IS) > D) Thalamus

Using the connection above, the activation of cell A does what to the activation of cell C?

a. decreases it
b. increases it
c. does nothing
d. reclassifies it as inhibitory

Answer 16

a. Decreases it

Question 17

Using diagram above, activation of cell A (cortex) does what to the activation of cell D (thalamus)?
a. decreases it
b. increases it
c. does nothing
d. reclassifies it as inhibitory

Answer 17

B. increases it

Question 18

Same as above, which cell is inhibited as a result of the activation of cell A (cortex)
a. A (cortex)
b.B (caudate/putamen)
c. C (globus pallidus)
d. D (thalamus)

Answer 18

c. C globus pallidus

Question 19

Same as above, which cell is disinhibited as a result of activation of cell A (cortex)?
a. A (cortex)
b. B (caudate/putamen)
c. C (globus pallidus)
d. D (thalamus)

Answer 19

d. D (thalamus)

Question 20

Using the connection diagram which cells are tonic active in that system
a. A and B
b. B and C
c. B and D
d. C and D

Answer 20

C (globus pallidus) and D (thalamus)

Question 21

Using the diagram what pathway is shown
a. direct
b. indirect
c. hyperdirect
d. none of these

Answer 21

a. direct

Question 22

Using the diagram, activation of cell A will result in
a. increased muscle tone
b. decreased muscle tone
c. blockade of movement
d. tremors

Answer 22

a. increased muscle tone

Question 23

Describe the infectious agent in prion diseases and how it causes infection in acquired or transmitted cases?

Answer 23

The infectious agent in prion diseases is a misfolded protein that lacks nucleic acid, and it is transmitted when the PrP^c protein misfolds in a way that causes others to misfold and aggregate

Question 24

How is the affected gene different in an individual who has huntington’s disease?

Answer 24

the affected gene (huntingtin) is different because it has an abnormally large amount of repeating DNA sequences called CAG repeats

Question 25

Very breifly define or describe a protein's primary, secondary, tertiary, and quaternary structure

Answer 25

A protein's primary structure is a sequence of amino acids, a secondary structure is a beta sheet or alpha helix, a tertiary structure is a three-dimensional structure of the polypeptide chain, and the quaternary structure is a structure formed by the interactions between multiple polypeptide chains

Question 26

Briefly describe the relationship between the level of activation of the GPi and muscle tone

Answer 26

The level of activation in the GPi affects the amount of movement from the muscle tone. In the direct pathway the striatum inhibits the GPi cell's normally tonic active state which inhibits the thalamus, so now with it being inhibited the thalamus is able to send glutamate to the motor cortex and movement happens. In the indirect pathway the subthalamic nucleus blocks the inhibition of the GPe cells so the GPi cells are disinhibited and will continue to fire GABA onto the thalamus preventing movement

Question 27

Which site is affected by Parkinson's disease

Answer 27

substania nigra compacta

Question 28

How does the affected area lead to the symptoms of Parkinson's disease? (Include NT involved and how they're involved)

Answer 28

There is a loss of dopamine functioning in the substania nigra which leads to a loss of excitation and disinhibition of volitional movement initiation (weakens direct pathway)

Question 29

Which site is affected by Huntington's disease

Answer 29

striatum

Question 30

How does the affected area lead to the symptoms of Huntinton's disease? (Include NT involved and how they're involved)

Answer 30

Symptoms arise from a combo of neuronal degeneration in striatum and neurotransmitter dysregulation (GABA, DA, Glu, and ACh) Loss of GABAergic MSNs in striatum reduces inhibitory output to the GPe, this disinhibition of the GPe causes excessive inhibition of the subthalamic nucleus impairing normal movement control, DA signaling may become imbalanced contributing to chorea

Question 31

What is the role of Dopamine in the direct pathway

Answer 31

Dopamine in the direct pathway increases the excitability of the striatum which makes glutamate receptors more sensitive. It also amplifies pathway's excitatory input and reduces inhibitory output from GPi to thalamus

Question 32

What is the role of dopamine in the indirect pathway? Be precise

Answer 32

dopamine reduces the activity of D-2 receptor expressing neurons in striatum which disinhibits the GPe, diminishing GPi activity and facilitates voluntary movement by decreasing thalamic inhibition