Question
Write any four ways used to introduce a desired DNA segment into a bacterial cell in recombinant technology experiments.

Answer

Four-ways of introducing the desired DNA segment into a bacterial cell are as follows:
i. Competent host (For transformation with recombinant DNA):
a. For transformation, bacterial cells are treated with a specific concentration of calcium which increases the efficiency with which DNA enters the bacterium through pores in its cell wall.
b. Cells with recombinant DNA are incubated on ice, followed by placing them briefly at 42°C (heat shock) and then putting them back into ice.
This enables the bacteria to take up recombinant DNA.
ii. Micro-injection: Recombinant DNA is directly injected into the nucleus of an animal cell.
iii. Biolistic or Gene gun: Plant cells are bombarded with high-velocity micro-particles of gold or tungsten coated with DNA.
iv. "Disarmed pathogen"vectors: (Ti- plasmid); retroviruses which when allowed to infect the cell, transfer the recombinant DNA into the host.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

One chromosome contains one molecule of DNA. In eukaryotes the length of the DNA molecule is enormously large. Explain how such a long molecule fits into the tiny chromosomes seen at metaphase.
Write about the role of microbes in nitrogen fixation.
What do you mean by seed ? Describe the process of seed formation ?
The graph given below shows the variation in the levels of ovarian hormones during various phases of menstrual cycle:

Specify the source of the hormone marked in the diagram.

How does the disease spread? Write briefly.
A flower of brinjal plant following the process of sexual reproduction produces 360 viable seeds.
Answer the following questions giving reasons:
How many ovules are minimally involved?
Using a Punnett Square, workout the distribution of phenotypic features in the first filial generation after a cross between a homozygous female and a heterozygous male for a single locus.
What is called immunity? How many types are there? Describe innate immunity.
Ramesh is a small scale farmer and holds 2.5 acres of land. He would like to increase the yield in his farm. Rahul, a student of MSc. (Agriculture) advised him to go to the agricultural department centre of his locality to get biofertilisers according to the variety of the crop. He also suggested Ramesh to stop the use of chemical fertilisers.
  1. Explain the term biofertilisers.
  2. Name the biofertiliser that is used mostly in paddy fields.
  3. What are the values shown by Rahul?
  1. Give reasons for:
  1. Both strands of DNA are not copied during transcription.
  2. Transcription and translation in bacteria can be coupled.
  1. Differentiate between the process of transcription in prokaryotes and eukaryotes.