Genetic Engineering Multiple Choice Questions on “Expression of Coding Section In-Vitro”.
1. If an expression of the coding sequence is to be carried in the vitro, then which of the statement holds true?
a) The extract in which the host DNA constructs are incubated is capable of translation only
b) The extract in which the host DNA constructs are incubated is capable of transcription only
c) The extract is made up of lysate of E. coli cells, containing RNA polymerase, ribosomes, tRNAs etc
d) Non radiolabelled amino acids are used
Answer: c
Explanation: If an expression of the coding sequence is to be carried in vitro, then the extract in which host DNA constructs are incubated is capable of both transcription and translation. The extract is made up of lysate of E. coli cells, containing RNA polymerase, ribosomes, tRNAs etc. Radiolabelled amino acids are used and thus detection becomes easier.
2. If translation and transcription are taking place together, the reaction is called as ______ and if they are carried out separately, it is called as _______
a) coupled, linked
b) linked, coupled
c) grouped, separate
d) grouped, individual
Answer: a
Explanation: If translation and transcription are carried out together, it is known as a coupled reaction. If they are carried out separately then they are known as linked reactions.
3. If translation and transcription are carried out separately, then what is added to carry out translation?
a) DNA polymerase
b) RNA polymerase
c) Taq polymerase
d) Tfl polymerase
Answer: b
Explanation: The added RNA polymerase carries out the translation in a separate reaction by the use of lysate of wheat gram cells.
4. If the screening of the DNA constructs is carried out in pooled batches then it takes less time.
a) True
b) False
Answer: a
Explanation: If the screening of DNA constructs is carried out in pooled batches then less time is taken. Once the pooled batch is identified with recombinants then each member is screened.
5. Choose the incorrect statement for the open reading frame.
a) It is helpful in deciding whether the clone is correct or not
b) It consists of an initiation codon
c) It consists of a termination codon
d) The presence of introns doesn’t affect the open reading frame
Answer: d
Explanation: Open reading frame is very important in deciding whether the clone is correct or not. It consists of an initiation codon, followed by a stretch of DNA and termination codon. The presence of introns the open reading would be affected and makes detection difficult.
6. Introns are ________ in nature and the sequence is _______ than exons.
a) coding, less random
b) non-coding, less random
c) non-coding, more random
d) coding, more random
Answer: c
Explanation: Introns are non-coding in nature and thus the sequence is having a more random base composition than exons. Exons are coding sequences.
7. If the genome size is small, then sequencing of the entire genome is ___________
a) easy
b) difficult
c) independent of the size of genome
d) not possible