LS23L Lab F

T or F: In this lab, the purpose of spectrophotometry is to measure protein activity.

False

T or F: In this lab, you will use Coomassie Blue to visualize your protein on the gel.

False

T or F: According to the lab safety sheet, in the Polyacrylamide and Agarose Gels lab, used microcentrifuge tubes and pipette tips should be disposed of in the regular trash.

True

T or F: The agarose gels used in this lab are cast with GelGreen, a less toxic alternative to ethidium bromide.

True

What is the optimum wavelength of UV light absorbed by DNA? Select one: a. 260 b. 280 c. 320 d. 570 e. 680

a. 260

According to the lab safety sheet, which of the following is a potential hazard you will face in the Polyacrylamide and Agarose Gels lab? (Check all that apply) Select one: a. Chemicals causing respiratory tract, eye and skin irritation b. None of these c. Corrosive chemicals d. Carcinogenic chemicals e. Water reactive chemicals

a. Chemicals causing respiratory tract, eye and skin irritation

Which of the following techniques allows the determination of a protein's mass in its native form? Select one: a. gel filtration b. SDS-page c. Western Blot d. RASMOL e. ultracentrifugation

a. gel filtration

What are the functions of SDS in gel electrophoresis for estimating protein sizes? I. Disrupts hydrogen bonding in proteins, linearizing the protein II. Provides an overall negative charge on proteins, making the migration distance on gel a function of only protein size III. Intercalates between the amino acids of the protein allowing it to be visualized on the gel Select one: a. III only b. I and II c. II only d. I only e. I, II, and III

b. I and II

What kind of gel medium is used in SDS-PAGE? Select one: a. TBE b. Polyacrylamide c. FITC d. Agarose e. Ethidium Bromide

b. Polyacrylamide

Which method will you use in this lab to separate proteins based on size? Select one: a. RASMOL b. SDS-PAGE electrophoresis c. gel filtration d. agarose gel electrophoresis e. none of these

b. SDS-PAGE electrophoresis

Which of these substances is usually used to visualize proteins on a polyacrylamide gel? Select one: a. aniline blue b. coomassie blue c. phenol red d. ethidium bromide e. alcian blue

b. coomassie blue

After the treatment of proteins described in the lab manual, all proteins used in this lab should carry an overall ______ charge. Select one: a. positive b. negative

b. negative

Spectrophotometry provides a ______ measure of the concentration of DNA. Select one: a. qualitative b. quantitative

b. quantitative

The combination of gel filtration and SDS-PAGE can reveal the ______ structure of a protein. Select one: a. tertiary b. quaternary c. secondary d. primary

b. quaternary

What is the optimum wavelength of UV light absorbed by protein? a. 260 b. 680 c. 280 d. 570 e. 320

c. 280

Which of the following is not a similarity between performing a gel electrophoresis analysis on protein versus DNA? Select one: a. Both methods utilize electrical currents to mobilize the macromolecules. b. If performed correctly, the samples always move towards the anode in both methods. c. Both methods utilize SDS to create a uniform charge to mass ratio. d. Agarose gels would work for both protein and DNA gel electrophoresis. e. The larger the macromolecules are, the slower they migrate through the gel matrix in both methods.

c. Both methods utilize SDS to create a uniform charge to mass ratio.

What is the name of the method for separating charged molecules, such as proteins and nucleic acid, in an electrical field? Select one: a. Electroseparation b. Electroporation c. Electrophoresis d. Chemophoresis e. Denaturation

c. Electrophoresis

Agarose gel electrophoresis as used in the lab you will be performing this week can do all of the following except: Select one: a. confirm the presence of purified DNA visually b. show whether the DNA is the correct size c. give a sequence for the amplified DNA d. show whether the DNA product is composed primarily of primer-dimer e. give a qualitative overview of the DNA purity

c. give a sequence for the amplified DNA

In spectrophotometry, ___ nm wavelength absorption corresponds with ___ while the ___ nm wavelength absorption corresponds with protein. Select one: a. 260, Carbohydrate, 280 b. 280, Protein, 260 c. 260, DNA, 240 d. 260, DNA, 280 e. 240, Protein, 260

d. 260, DNA, 280

Some of the chemicals/materials you will use in the Polyacrylamide and Agarose Gels lab include (check all that apply): a. Ethidium bromide b. Chloroform c. none of these d. Tris glycine polyacrylamide gels e. TGS (tris-glycine-SDS) buffer

d. Tris glycine polyacrylamide gels e. TGS (tris-glycine-SDS) buffer

In the Polyacrylamide and Agarose Gels lab, when working with your protein or DNA sample you must wear: Select one: a. Gloves b. Lab coat c. Safety goggles d. Standard lab attire e. All of these

e. All of these

What chemical must be applied to proteins prior to running gel electrophoresis in order to denature the protein and give it an overall negative charge? Select one: a. Agarose b. EtBr c. Chelex d. Acrylamide e. SDS

e. SDS

What is the commonly used unit to describe the size of a protein introduced in this lab? Select one: a. gram/kilogram b. base/kilobase c. centimeters d. none of these e. dalton/kilodalton

e. dalton/kilodalton