Question

Which of the following statements represents 'cloning'?

A) All of the cells are derived from one cell and are genetically identical.
B) A gene from one organism has been inserted into a vector and successfully introduced into a host cell.
C) All of the cells in a particular organism are identical.
D) All of the above

Answer 1

Hint: It is an important aspect of recombinant DNA technology. DNA cloning is the production of a large number of identical DNA molecules from a single ancestral DNA molecule. The essential characteristic of cloning is that the desired DNA fragments must be selectively amplified, resulting in a large increase in copy number of selected DNA sequences.

Complete step-by-step answer:
Cloning can be of different types-
1)cell-based
2)cell-free based DNA cloning.

Cloning involves multiple rounds of DNA replication catalyzed by a DNA polymerase acting on one or more types of template DNA molecule. DNA Cloning means the production of identical cells so option A) is correct as all the cells produced after cloning are genetically identical.
Isolation of recombinant DNA clones can be done by harvesting expanded cell cultures and selectively isolating the recombinant
Recombinant DNA molecules are constructed in vitro covalent attachment of desired DNA fragments to a replicon so option B also defines cloning or is a process for cloning.
And option C is also correct as all the cells after cloning is identical.

Therefore the correct answer is Option D.

Note: Cell-free DNA cloning involves PCR polymerase chain reaction which is a newer form of DNA cloning that is mediated and is conducted entirely in vitro. PCR is a revolutionary technique used for selective amplification of a specific target sequence of nucleic acid by using short primers.