Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Neuroscience Lab > Exam 3 > Flashcards

Exam 3 Flashcards

1
Q

What are the steps for working on the microscope?

A
  1. Set objective to 2.5x using grippy strip
  2. Fix the light using rod and intentisity buttons
  3. Place your slide on (white on the right)
  4. Move the stage up
  5. Adjust the exposure on the computer & focus on the image
  6. Move to white section and adjust white balance
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

For light microscopy, why is tissue usually fixed with 4% formaldehyde in phosphate buffer?

A

This cross-links proteins by the formation of methylene bridges so that the tissue does not degrade and the structure of the cells is stable.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Where is the needle placement in cardiac perfusion surgery?

What is cut?

A

A perfusion needle is placed through the left ventricle and into the aorta. The right atrium is cut.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Why is the temperature the brain is frozen at important (@-30C)?

A

Too cold and the brain will split, but too warm and the freezing is too slow and ice crystals form causing the brain to look like swiss cheese.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is cresyl violet?

A

A synthetic dye used to stain the cell bodies in nervous system tissue purple.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What type of stain is cresyl violet staining?

What does that mean?

A

Cresyl violet is a type of Nissl staining. (Nissl substance/body = rough ER)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Why does cresyl violet bind to RNA?

A

RNA is acidic and basophilic, so it binds dyes like cresyl violet.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is Luxol fast blue staining?

A

Myelin staining to visualize fiber tracts.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What does a Golgi stain use?

A

Uses silver nitrate to stain whole neurons, including processes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the general method for cresyl violet staining?

A
  1. Wash sections in distilled water
  2. Submerge in cresyl violet stain
  3. Dehydrate in an ascending series of alcohol baths
  4. Clear tissue with Histoclear
  5. Coverslip with permount mounting medium
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are bregma and lambda?

Where are they found?

A

Bregma and lambda are landmarks on the skull, based on the fusion of the different skull bone plates.

Bregma is found where the coronal suture meets the saggital suture. Lambda is found where the saggital and lambdoid sutures meet.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the most external and internal layer of the cerebral cortex?

A

Layer I is the most external layer, Layer VI is the most internal layer.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the hippocampus studied for?

A

Neural circuits in hippocampus are studied for LTP and LTD which are processes critical in learning and memory.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the preforant path in the hippocampus?

A

Major input from entorhinal cortex to dentate gyrus granule cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the axons of the DG?

Where do they synapse?

A

Axons of DG = mossy fibers, synapse with CA3 pyramidal cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Where do the axons of CA3 branch?

A

Either leave the hippocampus via fornix OR form Schaffer collaterals which synapse with pyramidal cells of CA1.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are the different nuceli of the thalamus and their functions?

A
  • Ventral posterior nucleus - somatosensory relay
  • Ventral lateral nucleus - motor
  • Lateral Geniculate nucleus - visual thalamus
  • Medial Geniculate Nucleus - auditory thalamus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the different nuclei that you would see in the rostral hypothalamus and their functions?

A
  • Suprachiasmatic nucleus - biological clock
  • Supraoptic nucleus - water balance
  • Paraventricular nucleus - autonomic and neuroendocrine functions
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What are the different nuclei that you would see in the caudal hypothalamus and their functions?

A
  • Ventromedial nucleus - feeding
  • Arcuate nucleus - feeding & growth hormone regulation
  • Dorsomedial nucleus - feeding, drinking, circadian activity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the role of the caudate putamen in rats?

A

Voluntary movement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is the role of the Nucleus Accumbens in rats?

A

Motivation, aversion, reward, and reinforcement behavior

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is the role of the septum in rats?

A

Pleasure center

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is the role of the piriform cortex in rats?

What layer is this cortex?

A

Layer III; olfaction

24
Q

What is immunohistochemistry?

A

The process of visualizing a specific protein within tissue using an antibody that binds selectively to that protein, and is conjugated to something that will enable it to be visualized.

25
Q

What is a buffer?

How is it made?

A

Keep the pH of a solution relatively stable. A buffer is made when you mix a weak acid with its conjugate base.

26
Q

What is the buffer system that maintains our blood pH?

A

Carbonic acid (H2CO3) and its conjugate base bicarbonate (HCO3-)

27
Q

What is a phosphate buffer?

A

A phosphate buffer system is used inside your body’s cells.

28
Q

What is phosphate buffered saline?

What is it used for?

A

Contains different salts at concentrations similar to those found in physiological systems, used for washing tissue.

29
Q

What is a blocking buffer used for?

What is it made up of?

A

Used for “blocking” non-specific binding of antibody to tissue.
- contains bovine serum albumin (protein) and carrageenan (polysaccharide) to bind weakly to the brain section and block non-specefic binding of the glycoprotein antibody
- contains Trition X-100 to allow antibody to pass through cell membranes to bind

30
Q

What is the innate immune response?

A

First respone to an invading pathogen. Very quick, and non-specialized.

31
Q

What is the adaptive immune response?

A

Slow response the first time a pathogen is encountered, but faster for subsequent exposures. Very specific, involves T cells and B cells that recognize specific anitgens.

32
Q

What is an antigen?

A

Is anything that generates an adaptive immune response. Often other proteins, but can be polysaccharides or lipids.

33
Q

What is an antibody?

What generates them?

A

Glycoprotein that recognizes and binds to a specific antigen. Generated by differentiated B cells of the adaptive immune system.

34
Q

How many types of antibody can one plasma cell secrete?

A

Each plasma cell secretes many copies of only one specific antibody that recognizes one specific antigen.

35
Q

Why is IgG used for immunohistochemistry?

What is an IgG?

A

IgG (antibody/ immunoglobulin) has the concentration in blood.

36
Q

What is the structure of an antibody?

A

Made of 4 peptide chains (2 heavy, 2 light.) Has a Y shape with an identical antigen binding sit at the ends of each of the 2 arms (Fab region). The other end is not specific for antigen binding (Fc region).

37
Q

How do you generate a polyclonal antibody?

What is a polyclonal antibody?

A

To generate a polyclonal antibody to a particular protein, the protein is injected into an animal. The animal will generate different plasma cells that produce different antibodies that recognize the different antigens on the protein.

A polyclonal antigen for a particular protein really contains multiple antibodies against that protein.

38
Q

What is a monoclonal antibody?

A

A monoclonal antibody comes from cells derived from a single B-cell/plasma cell line. Each plasma cell makes one type of antibody, hence a monoclonal antibody contains a single type f antibody.

39
Q

How do you develop a monoclonal antibody?

A
  1. To develop a monoclonal antibody against a protein, the mouse is injected with the protein, which generates an immune response.
  2. A specific antibody cell is fused with a tumor cell to form a hybridoma.
  3. The hybridoma is grown in culture, and will endlessly divide and produce antibody.
40
Q

What does immunohistochemistry require?

A
  • a tissue that has been processed appropriately
  • a monoclonal or polyclonal antibody to bind selectively to the antigen of interest
  • a way to visualize the antibody after binding
41
Q

How do you use an enzyme to visulize an antibody?

A

Antibody is conjugated to an enzyme that catalyzes a reaction to form an insoluable color product.

42
Q

What is immunofluorescence?

A

Antibody is conjugated to a fluorophore that can be visualized more direclty with fluorescent microscopy.

43
Q

What is direct immunofluorescence?

What is added into the solution and why?

A

The antibody is conjugated to a fluorophore that can be visualized by exposing it to light of a specific wavelength, and detecting the light that is emitted by the fluorophore. The antibody can also bind to proteins and polysaccharides in tissues non-specifically. To help prevent this, we use a solution that contains an excess of bonine serum albumin and carrageenan.

44
Q

What is indirect immunohistochemistry?

What is the second antibody made from?

A

Sometimes the primary antibody is not conjugated to an enzyme or fluorophore. In order to dectect it, a secondary antibody, that is conjugated to the a fluorophore or enzyme is used to dected the primary antibody.

The second anitbody is made from a different animal.

45
Q

What is the ABC method?

A

It can amplify the signal because avidin can bind multiple biotin molecules.
- A reporter enzyme conjugated with biotin is pre-incubated with avidin in a specific concentration ratio. The complex is added to the tissues and and the avidin-enzyme complex binds to the second antibody.

46
Q

What does the antibody stain on a gel?

Why would it have multiple bands?

A

It will stain one band of appropriate molecular weight.

Multiple bands if the protein has multiple moleuclar configurations.

47
Q

What is the gold standard necessary to show you’re staining what you think you are staining?

A

If you remove the molecule of interest, will the antibody still stain the tissue?

48
Q

What are other controls to show that you are staining what you think you are staining?

A
  • preincubate the antibody with an excess of the immunizing molecule
  • show colocalization with the mRNA that codes for the protein
  • show that the staining is consistent with classic morphology and distribution
49
Q

What is situ hybridization?

A
  • Used to detect RNA
  • Based on hybridization of sense to antisense sequences
  • “Probes” can be labeled with a fluorophore
50
Q

What is CLARITY?

A

Post-mortem brain tissue is cleared of lipids, while the proteins and nucleic acids remain used a clear hydrogel. The lipid-free cells are transparents and are permeable to antibodies.

51
Q

What is and what happens in the first phase of fluorescence?

A

Stage 1: Excitation
- a photon of energy is supplied by an external source and is absorbed by the flurorphore, creating an excited state.

52
Q

What is and what happens in the second phase of fluorescence?

A

Stage 2: Excited-State Lifetime
- The fluorophore undergoes conformational changes and is subject to a number of different types of interactions with its molecular enviroment
- the engery of S1’ is partially dissipated, resulting in a lower energy excited state from which fluorescence emission originates

53
Q

What is and what happens in the third phase of fluorescence?

A

Stage 3: Fluorescence Emission
- The reaminder of the energy is emitted as a photon of energy returning the fluorophore to its ground state

54
Q

Is the energy of the emitted photon higher or lower than the excitation photon?

What about the wavelength?

A

The energy of the emitted photon is lower, and therefore of longer wavelength than the excitation photon

55
Q

What is photobleaching?

A

The excitation and photon emission from a fluorophore is cyclical, and the fluorophore can be repeatedly excited until it it irreversibly damaged (photobleaching)

56
Q

What is the Stokes shift?

What does it mean if the Stokes shift is smaller?

A

The distance between the peak excitation and emission wavelength.

Fluorophores with smaller stokes shifts giver higher background signal because of the small difference between excitation and emission wavelength.

57
Q

How do you distinguish between multiple fluorophores?

A

The light is passed through a filter cube that has a series of 3 filters, designed only to let light within narrow wavelength ranges through.

Neuroscience Lab (3 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions