Questions and answers for exam Preparation

MCQs

Total Questions : 100 | Page 2 of 10 pages

Question 11. There are a large number of protein folds available, compared to millions of protein sequences.

True
False
May be True or False
Can't say

Discuss Question

Answer: Option B. -> False
Answer: (b).False

Question 12. In the pairwise energy based method, a protein sequence is searched for in a structural fold database to find the best matching structural fold using ______ criteria.

sequence-based
structure-based
energy-based
residue-based

Discuss Question

Answer: Option C. -> energy-based
Answer: (c).energy-based

Question 13. Threading or structural fold recognition predicts the structural fold of an unknown protein sequence by fitting the sequence into a structural database and selecting the best-fitting fold.

True
False
May be True or False
Can't say

Discuss Question

Answer: Option A. -> True
Answer: (a).True

Question 14. The next step in the pairwise energy based method is to build a crude model for the target sequence by replacing aligned residues in the template structure with the corresponding residues in the query.

True
False
May be True or False
Can't say

Discuss Question

Answer: Option A. -> True
Answer: (a).True

Question 15. The algorithms used here can be classified into two categories, pairwise energy based and profile based.

True
False
May be True or False
Can't say

Discuss Question

Answer: Option A. -> True
Answer: (a).True

Question 16. Which of the following is not correct?

The rigid double bond structure forces atoms associated with the peptide bond to lie in the same plane, called the dipeptide plane
A peptide bond is actually a partial double bond owing to shared electrons between O=C–N atoms
Because of the planar nature of the peptide bond and the size of the R groups, there are considerable restrictions on the rotational freedom by the two bonded pairs of atoms around the peptide bond
The angle of rotation about the bond is referred to as the dihedral angle (also called the torsional angle)

Discuss Question

Answer: Option A. -> The rigid double bond structure forces atoms associated with the peptide bond to lie in the same plane, called the dipeptide plane
Answer: (a).The rigid double bond structure forces atoms associated with the peptide bond to lie in the same plane, called the dipeptide plane

Question 17. Which of the following is not correct about the Coils and Loops?

They are regular structures
They are irregular structures
The loops are often characterized by sharp turns or hairpin-like structures
If the connecting regions are completely irregular, they belong to random coils

Discuss Question

Answer: Option A. -> They are regular structures
Answer: (a).They are regular structures

Question 18. Which of the following is not correct about the β-sheet?

A β-sheet is a fully extended configuration built up from several spatially adjacent regions of a polypeptide chain
Each region involved in forming the β-sheet is a β-strand
The β-strand conformation is pleated with main chain backbone zigzagging and side chains positioned on same sides of the sheet
β-Strands are stabilized by hydrogen bonds between residues of adjacent strands

Discuss Question

Answer: Option C. -> The β-strand conformation is pleated with main chain backbone zigzagging and side chains positioned on same sides of the sheet
Answer: (c).The β-strand conformation is pleated with main chain backbone zigzagging and side chains positioned on same sides of the sheet

Question 19. Which of the following is not correct about the α-Helices?

An α-helix has a main chain backbone conformation that resembles a corkscrew
Nearly all known α-helices are right handed, exhibiting a leftward spiral form
Nearly all known α-helices are right handed, exhibiting a rightward spiral form
In right handed helix, there are 3.6 amino acids per helical turn

Discuss Question

Answer: Option B. -> Nearly all known α-helices are right handed, exhibiting a leftward spiral form
Answer: (b).Nearly all known α-helices are right handed, exhibiting a leftward spiral form

Question 20. Which of the following is not correct about the stabilizing Forces?

Protein structures from secondary to quaternary are maintained by noncovalent forces
They include electrostatic interactions but not van der Waals forces, and hydrogen bonding
Electrostatic interactions are a significant stabilizing force in a protein structure
Electrostatic interactions occur when excess negative charges in one region are neutralized by positive charges in another region

Discuss Question

Answer: Option B. -> They include electrostatic interactions but not van der Waals forces, and hydrogen bonding
Answer: (b).They include electrostatic interactions but not van der Waals forces, and hydrogen bonding