Tag: biotechnology: principles and processes

Quizzes (11) Questions (27)

Questions Related to biotechnology: principles and processes

Multiple choice botany biotechnology: principles and processes manipulation of dna electrophoresis isolation and separation of dna

Select the incorrect Statement regarding DNA replication with respect to the template strand

  1. Leading strand is formed in 5 $\rightarrow$ 3 direction.
  2. Okazaki fragments are formed in 5 $\rightarrow$ 3 direction.
  3. DNA polymerase catalyses polymerisation in 5 $\rightarrow$ 3 direction.
  4. DNA polymerase catalyses palymerisation in 3 $\rightarrow$ 5 direction.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Since DNA polymerase requires a free 3' OH group for initiation of synthesis, it can synthesize in only one direction by extending the 3' end of the preexisting nucleotide chain. Hence, DNA polymerasemoves along the template strand in a 3'–5' direction, and the daughter strand is formed in a 5'–3' direction.

So, the correct answer is 'DNA polymerase catalyses polymerisation in 5 
→→ 3 direction'

Multiple choice botany biotechnology: principles and processes manipulation of dna electrophoresis isolation and separation of dna

The sequence of strategies involved in the isolation of a gene of interest from a plant cell during the process of rDNA technology

  1. Dissolution of biological membrane

  2. Enzymatic digestion of cell wall

  3. Precipitation of DNA

  4. Removal of DNA by spoiling
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Isolation of the Genetic Material (DNA):

Nucleic acid is the genetic material, which is present in all living organisms. In majority of organisms, this is present in the form of deoxy-ribonucleic acid (DNA). DNA must be present into pure form, i.e., free from other macro-molecules (like proteins, RNA, enzymes, etc.) in order to cut the DNA with restrictor enzymes.

Isolation of genetic material (DNA) is carried out in the following steps:

(a) Since the DNA is enclosed within the membranes, so, in order to release DNA along with other macro-molecules such as proteins, polysaccharides and lipids, bacterial cells/plant or animal tissues are treated with the enzyme lysozyme (bacteria), cellulose (plant cells), chitinase (fungus), respectively.

(b) RNA can be removed by the treatment with ribonuclease, whereas proteins can be removed by the treatment with protease.

(c) Other molecules can be removed by appropriate treatments and ultimately purified DNA will precipitate out, after the addition of chilled ethanol. This can be seen as collection of fine threads in the suspension.

So, the correct answer is “Precipitation of DNA”.

Multiple choice botany biotechnology: principles and processes manipulation of dna electrophoresis isolation and separation of dna

During the process of isolation of DNA, chilled ethanol is added to

  1. Break open the cell to release DNA

  2. Facilitate action of restriction enzymes

  3. Remove proteins such as histones

  4. Precipitate DNA
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Chilled ethanol is used in DNA isolation because DNA is insoluble in ethanol, causing it to precipitate out of the solution as fine threads.

Multiple choice botany biotechnology: principles and processes manipulation of dna electrophoresis isolation and separation of dna

Insect-resistant transgenic cotton has been produced by inserting a piece of DNA from.

  1. An insect

  2. A bacterium

  3. A wild relative of cotton

  4. A virus
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Insect-resistant transgenic cotton, commonly known as Bt cotton, is created by inserting crystal protein genes (cry genes) derived from the soil bacterium Bacillus thuringiensis into the cotton genome.

Multiple choice botany biotechnology: principles and processes manipulation of dna electrophoresis isolation and separation of dna

A technique utilized by a group of biologists to isolate an antifreeze gene found in cold water species of fish and introduce it into the genome of a different organism is called as 

  1. Cloning

  2. Artificial selection

  3. Selective breeding

  4. Genetic engineering

  5. Sexual recombination
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
Genetic engineering is the branch of science which deals with the modification of genes. The desired genes is isolated from the host like the gene for antifreeze protein and are inserted into the vectors. The vectors carries the foreign gene into the desired organism like the fish and then the gene gets introduced into the genome of fish, resulting in the production of the protein.
Thus, the correct answer is option 'Genetic engineering'.