Question:
Expression of a particular gene helps to identify transformants. What is this gene known as ?
Expression of a particular gene helps to identify transformants. What is this gene known as ?
Show Hint
A selectable marker, such as an antibiotic resistance gene, lets only the transformants survive.
Updated On: Oct 22, 2026
- Plasmid
- Structural gene
- Selectable marker
- Intron
Show Solution
Verified By Collegedunia
The Correct Option is C
Solution and Explanation
Step 1: Understanding the Concept:
In recombinant DNA work, only a few host cells take up the vector. These are called transformants.
We need a way to separate the transformants from non-transformants.
Step 2: The role of a selectable marker:
A gene such as an antibiotic resistance gene (for example ampicillin resistance) sits on the vector.
Only transformed cells express it, so only they survive on a medium with that antibiotic. This is a selectable marker.
Step 3: Why other options are wrong:
A plasmid is the whole vector, not a single gene, so (A) is wrong.
A structural gene codes for a protein product, but it does not identify transformants, so (B) is wrong.
An intron is a non-coding part of a eukaryotic gene that is removed from mRNA, so (D) is wrong.
Final Answer:
The gene whose expression identifies transformants is a selectable marker, option (C).
In recombinant DNA work, only a few host cells take up the vector. These are called transformants.
We need a way to separate the transformants from non-transformants.
Step 2: The role of a selectable marker:
A gene such as an antibiotic resistance gene (for example ampicillin resistance) sits on the vector.
Only transformed cells express it, so only they survive on a medium with that antibiotic. This is a selectable marker.
Step 3: Why other options are wrong:
A plasmid is the whole vector, not a single gene, so (A) is wrong.
A structural gene codes for a protein product, but it does not identify transformants, so (B) is wrong.
An intron is a non-coding part of a eukaryotic gene that is removed from mRNA, so (D) is wrong.
Final Answer:
The gene whose expression identifies transformants is a selectable marker, option (C).
Was this answer helpful?
0
0
Top CBSE CLASS XII Biology Questions
- All algae have
- With a neat, labelled diagram, describe the parts of a typical angiosperm ovule.
- With a neat diagram explain the 7-celled, 8-nucleate nature of the female gametophyte
- Draw a labeled diagram of male reproductive system.
- Draw a labeled diagram of female reproductive system.
View More Questions
Top CBSE CLASS XII Biotechnology Questions
- Make a chart(with diagrammatic representation)showing a restriction enzyme, the substrate DNA on which it acts, the site at which it cuts DNA and product it produces.
Explain briefly:
(a) PCR
(b) Restriction enzyme and DNA
(c) Chitinase
Collect 5 examples of palindromic DNA sequences by consulting your teacher. Better try to create a palindromic sequence by following base-pair rules.
- Can you list 10 recombinant proteins which are used in medical practice? Find out where they are used as therapeutics (Use the internet).
- From what you have learnt, can you tell whether enzymes are bigger or DNA is bigger in molecular size? How did you know?
View More Questions
Top CBSE CLASS XII Questions
- 2, b, c are in A.P. and the range of determinant $\begin{vmatrix}1&1&1\\ 2&b&c\\ 4&b^{2}&c^{2}\end{vmatrix}$ is [2, 16]. Then find range of c is
- A boy of mass 50 kg is standing at one end of a, boat of length 9 m and mass 400 kg. He runs to the other, end. The distance through which the centre of mass of the boat boy system moves is
- A capillary tube of radius r is dipped inside a large vessel of water. The mass of water raised above water level is M. If the radius of capillary is doubled, the mass of water inside capillary will be
- A circular disc is rotating about its own axis. An external opposing torque 0.02 Nm is applied on the disc by which it comes rest in 5 seconds. The initial angular momentum of disc is
- A circular disc is rotating about its own axis at uniform angular velocity \(\omega.\) The disc is subjected to uniform angular retardation by which its angular velocity is decreased to \(\frac {\omega}{2}\) during 120 rotations. The number of rotations further made by it before coming to rest is
View More Questions