Ask Question, Ask an Expert


Ask Chemistry Expert

Multiple Choice problems based on the Primary, Secondary and Tertiary structures of Proteins.

1. In an α helix, the R groups on the amino acid residues:
a. Alternate between the outside and the inside of the helix.
b. Are found on the outside of the helix spiral.
c. Cause only right-handed helices to form.
d. Generate the hydrogen bonds that form the helix.
e. Stack within the interior of the helix.

2. A d-amino acid would interrupt a α helix made of l-amino acids. Another naturally occurring hindrance to the formation of an α helix is the presence of:
a. a negatively charged Arg residue.
b. a nonpolar residue near the carboxyl terminus.
c. a positively charged Lys residue.
d. a Pro residue.
e. two Ala residues side by side.

3. A sequence of amino acids in a certain protein is found to be -Ser-Gly-Pro-Gly-. The sequence is most probably part of a(n):
a. Antiparallel β sheet.
b. Parallel β sheet.
c. α helix.
d. α sheet.
e. β turn.

4. Which of the following statements is false?
a. Collagen is a protein in which the polypeptides are mainly in the α-helix conformation.
b. Disulfide linkages are important for keratin structure.
c. Gly residues are particularly abundant in collagen.
d. an α-keratin chain contains 7-residue pseudo-repeats of nonpolar/polar arrangements.
e. α-keratin is a protein in which the polypeptides are mainly in the α-helix conformation.

5. Determining the precise spacing of atoms within a large protein is possible through the use of:
a. Cryo-electron microscopy.
b. Light microscopy.
c. Small angle neutron scattering.
d. Ramachandran plots.
e. X-ray diffraction of protein crystals.

6. Experiments on denaturation and renaturation after the reduction and reoxidation of the -S-S- bonds in the enzyme ribonuclease (RNase) have shown that:
a. Folding of denatured RNase into the native, active conformation requires the input of energy in the form of hat.
b. Native ribonuclease does not have a unique secondary and tertiary structure.
c. The completely unfolded enzyme, with all -S-S- bonds broken, is still enzymatically active.
d. The enzyme, dissolved in water, is thermodynamically stable relative to the mixture of amino acids whose residues are contained in RNase.
e. The primary sequence of RNase is sufficient to determine its specific secondary and tertiary structure.

7. Diseases caused by protein misfolding include:
a. Mad cow disease.
b. Alzheimer's.
c. cancer.
d. all of the above.
e. a & b only.

8. A tandem mass spectrometer can sequence short peptides by:
1. hydrolysis of peptide bonds with a strong acid and identifying the amino acids by HPLC.
2. fragmenting the peptide and comparing the fragment masses.
3. determining the absorbance of the peptide at 280 nm.
4. measuring the molecular mass of the whole peptide.
5. the transfer of magnetization from one nuclei to another.

10. Which of the following pairs of bonds within a peptide backbone show free rotation around both bonds?
a. Cα-C and N-Cα
b. C=O and N-C
c. C=O and N-Cα
d. N-C and Cα-C
e. N-Cα and N-C

11. Which of the following statements concerning the process of spontaneous folding of proteins is false?
i. It may be an essentially random process.
ii. It may be defective in some human diseases.
iii. It may involve a gradually decreasing range of conformational species.
iv. It may involve initial formation of a highly compact state.
v. It may involve initial formation of local secondary structure.

Chemistry, Academics

  • Category:- Chemistry
  • Reference No.:- M919286

Have any Question? 

Related Questions in Chemistry

Crbonic acid h2co3 is a diprotic acid withka1

Carbonic acid (H2CO3) is a diprotic acid withKa1 = 4.2×10-7and Ka2 = 4.8×10-11. Theion product for water is Kw = 1.0 × 10-14. What is the carbonate ion concentration[CO2-3] in a 0.037 M carbonic acid solution?

The combustion of so2g has keq560x104 at 350 degrees

The combustion of SO2(g) has Keq=5.60x10^4 at 350 degrees Celcius. If 0.350bar of SO2(g) and 0.762bar of O2(g) are mixed initially, what are the partial pressures of each of the three gases when the mixture reaches equil ...

For the reaction between permanganate ion and sufite ion in

For the reaction between permanganate ion and sufite ion in basic solution, the unbalanced equation is: MnO 4 -  + SO 3 2-   MnO 2  + SO 4 2- When this equation is balanced using the smallest whole number coefficients po ...

A 400g sample of an ideal gas occupies 124l at 23 degrees

A 4.00g sample of an ideal gas occupies 1.24L at 23 degrees Celcius and 1.12bar. What will be its volume at 14 degrees Celcius and 1.50bar?

Explain the geochemical differences between acidic mine

Explain the geochemical differences between acidic mine waters and basic mine waters.

If it is considered that drinking 800 ml of water per day

If it is considered that drinking 800 mL of water per day containing an arsenic concentration equal to the US EPA maximum contaminant level (MCL), delivers the dose to an adult that corresponds to a 1 in 10,000 excess ri ...

A how many milliliters of a 072nbspmhclnbspsolution do you

A. How many milliliters of a 0.72 MHCl solution do you need to obtain 0.0032 mol of HCl? B. A flask containing 470 mL of 0.50 M  H2SO4 was accidentally knocked to the floor. How many grams of NaHCO3 do you need to put on ...

If you take a 100 ml portion of a 148 m ammonia solution

If you take a 10.0 mL portion of a 14.8 M ammonia solution and dilute it to a total volume of 0.250 L, what is the concentration of ammonia in the final solution? Provide an answer correct to 2 significant figures. For e ...

Instructionscandidates are to answer all questionsall parts

Instructions: Candidates are to answer ALL questions/ALL parts of questions This assessment is designed to assess the following learning outcomes of the module: 1. Discuss and critically evaluate the principles and appli ...

1 show the alcohols you would obtain by reduction of the

1. Show the alcohols you would obtain by reduction of the following carbonyl compounds: (a) CH 3                   (b)          (c)  O      CH 3        |                                                         ||         ...

  • 4,153,160 Questions Asked
  • 13,132 Experts
  • 2,558,936 Questions Answered

Ask Experts for help!!

Looking for Assignment Help?

Start excelling in your Courses, Get help with Assignment

Write us your full requirement for evaluation and you will receive response within 20 minutes turnaround time.

Ask Now Help with Problems, Get a Best Answer

Section onea in an atwood machine suppose two objects of

SECTION ONE (a) In an Atwood Machine, suppose two objects of unequal mass are hung vertically over a frictionless

Part 1you work in hr for a company that operates a factory

Part 1: You work in HR for a company that operates a factory manufacturing fiberglass. There are several hundred empl

Details on advanced accounting paperthis paper is intended

DETAILS ON ADVANCED ACCOUNTING PAPER This paper is intended for students to apply the theoretical knowledge around ac

Create a provider database and related reports and queries

Create a provider database and related reports and queries to capture contact information for potential PC component pro

Describe what you learned about the impact of economic

Describe what you learned about the impact of economic, social, and demographic trends affecting the US labor environmen