Questions and answers for exam Preparation

MCQs

Total Questions : 232 | Page 18 of 24 pages

Question 171. After cleaving the sequence, the nature of the ends created by the type II endonuclease is __________

The ends created are always single stranded
The ends created are always double stranded
Either the ends are single stranded or they are double stranded
One end is single stranded and one end is double stranded

Discuss Question

Answer: Option C. -> Either the ends are single stranded or they are double stranded
Answer: (c).Either the ends are single stranded or they are double stranded

Question 172. A sequence is having two ends, 5’ and 3’. Which of the following statements is correct regarding the nature of the ends?

The 5’ end is having hydroxyl group
The 5’ end is having phosphate group
The 3’ end is having phosphate group
Any group can be present at any end

Discuss Question

Answer: Option B. -> The 5’ end is having phosphate group
Answer: (b).The 5’ end is having phosphate group

Question 173. In the case of blunt-end ligation, blunt ends can be generated by ___________

simply the action of restriction endonuclease which gives straight ends
the polishing of staggered ends
both the action of restriction endonuclease which gives straight ends and polishing of staggered ends
by the action of restriction endonuclease which gives staggered ends

Discuss Question

Answer: Option C. -> both the action of restriction endonuclease which gives straight ends and polishing of staggered ends
Answer: (c).both the action of restriction endonuclease which gives straight ends and polishing of staggered ends

Question 174. The sticky ends are held together by which type of bonds?

Hydrogen bond
Covalent bond
Ionic bond
Van-der-waal forces

Discuss Question

Answer: Option A. -> Hydrogen bond
Answer: (a).Hydrogen bond

Question 175. Ligation reaction can be both intramolecular and intermolecular in nature.

True
False
May be True or False
Can't say

Discuss Question

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

Question 176. The ligation reaction is more efficient in which case?

Blunt end ligation
Sticky end ligation
Both have the same efficiency
Depends on the reaction conditions

Discuss Question

Answer: Option B. -> Sticky end ligation
Answer: (b).Sticky end ligation

Question 177. Why sticky ended ligations are carried out at temperatures lower than room temperature?

It is so because the vibrational and kinetic energy of the molecules at room temperature is lower than that of the energy required to break the bonds holding the ends
The energy required to break the bonds holding the ends is very less than that of the kinetic and vibrational energy at room temperature
The enzyme carrying out ligation is unstable at low temperature
The sticky ends created, don’t just relegate at low temperature

Discuss Question

Answer: Option A. -> It is so because the vibrational and kinetic energy of the molecules at room temperature is lower than that of the energy required to break the bonds holding the ends
Answer: (a).It is so because the vibrational and kinetic energy of the molecules at room temperature is lower than that of the energy required to break the bonds holding the ends

Question 178. Phage based recombination systems are used for ____________

cleaving the molecules at specific sites
adding the molecules at specific sites
breakage and rejoining the molecules at specific sites
breakage at random sites

Discuss Question

Answer: Option C. -> breakage and rejoining the molecules at specific sites
Answer: (c).breakage and rejoining the molecules at specific sites

Question 179. Bacteriophage lambda is having a phage recombination system. Following are the characteristics of this system ____________

It is used for inserting phage genome into the bacterium
It is used for inserting bacterial genome into the phage
The specific site in bacteria is attB and that in phage is attP
The specific sites in both of them are called as attP

Discuss Question

Answer: Option A. -> It is used for inserting phage genome into the bacterium
Answer: (a).It is used for inserting phage genome into the bacterium

Question 180. Ligation enzymes are used for ligating newly synthesized okazaki fragments. What holds true for okazaki fragments?

Okazaki fragments are short fragments of DNA formed on the leading strand
Okazaki fragments are large fragments of DNA formed on the lagging strand
Okazaki fragments are short fragments of DNA formed on the lagging strand
Okazaki fragments are large fragments of DNA formed on the leading strand

Discuss Question

Answer: Option C. -> Okazaki fragments are short fragments of DNA formed on the lagging strand
Answer: (c).Okazaki fragments are short fragments of DNA formed on the lagging strand