NEET Important Chapter - Biotechnology Principles and Process

This article covers the notes for the Biotechnology principles and process according to the Biology NEET syllabus. This article is very useful and helpful for the NEET aspirants as it covers all the important topics of the chapter and also this covers the important questions of previous year question papers and solved examples.

The following document contains all of the important topics and provides the view of the exam pattern. By revising this document one can find out all the answers to the important questions related to the chapter such as what is Biotechnology, what are principles of  biotechnology, what are tools of recombinant DNA technology, what are cloning vectors, what are competent host, what is the process of recombinant DNA technology, what is downstream processing.

Important Topics of Biotechnology Principles and Process

• Principles of biotechnology

• Tools of Recombinant DNA Technology

• Processes of Recombinant DNA Technology

Important Concepts

Principles of Biotechnology

1. Genetic Engineering: Genetic engineering is considered to be a process that is responsible for altering the genetic structure of a particular organism by either introducing or removing a specific DNA from the organism's body. In the case of traditional animal and plant breeding, the organisms get involved in multiple crosses and make the selection of a particular organism that has a phenotype possible. Contrarily, in genetic engineering, only the gene gets transferred from one organism to another. This process is considered to be one of the fastest processes for inserting genes in any organism. Genetic engineering has the ability to cure different genetic disorders in humans by replacing the defective gene with a new and functioning one.

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2. Bioprocess Engineering

It is the planning, construction, execution, and revision of the biological and mechanical processes required to create new products within the life sciences.

• Recombinant DNA: The process used for producing new genetic combinations by joining different genetic material (DNA) together and inserting them into the host organisms from two different species or sources.

• Gene Cloning: DNA cloning can be described as the process of making multiple, identical copies of a particular piece of the genetic material or DNA fragment. In a typical DNA cloning process, the gene or other the target DNA fragment is first inserted into a circular piece of DNA, known as a plasmid. This is done using restriction enzymes that “cut and paste” the DNA. It produces a molecule of recombinant DNA.

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• Gene Transfer: The movement of genetic information between organisms is known as gene transfer. Gene transfer can be done by 2 methods, horizontal gene transfer, and vertical gene transfer. Horizontal gene transfer can be described as the transfer of genetic information between two independent organisms. It is also known as lateral gene transfer. It can be between the same species, different species. It can also occur between the bacterial species and eukaryotic species. Vertical gene transfer is the transfer of genetic information from parent to progeny. Horizontal gene transfer in humans and other multicellular cells is a rare event.

Tools of Recombinant DNA Technology

• Restriction Enzymes: Restriction enzymes are a type of protein that determines the size of a DNA molecule. They do this by cleaving foreign DNA or repeated sequences of DNA. Restriction enzymes are classified by their structure and the specificity of what they recognize.

• Ligase Enzyme: It is used to join two fragments. Sticky ends of the desired gene and the vector are attached with the help of ligase enzymes.

• Vector: It is generally a plastid plasmid used to carry and integrate the desired gene.

• Host: Competent host cell into which the recombinant DNA is inserted.

DNA Technology Steps

• Separation and isolation of DNA fragments

• Restriction Enzyme Digestion

• Amplification using PCR

• Ligation of DNA Molecules

• Insertion of DNA Recombinant Host

• Obtaining/Culturing the Foreign Gene Product

• Downstream Processing

Solved Examples/Problems of the Chapter

1. Describe DNA Processing.

Ans: A series of processes are applied to the product before it is made into a ready-for-marketing product. Separation and purification are two of the main functions. Preservatives are then added to the product. Clinical trials must be conducted on such preparations, as with drugs.

Key Points to Remember:

Transcription - “The process by which the information in a strand of DNA is copied into a new molecule of messenger RNA (mRNA)”.

Translation - The process in which ribosomes in the cytoplasm or endoplasmic reticulum synthesises proteins after the process of transcription of DNA to RNA in the cell's nucleus.

2. Describe PCR.

Ans: PCR: The polymerase chain reaction (PCR) is an in vitro molecular biology method that combines enzymatic amplification of a single DNA strand and creating millions of copies of the specific DNA sequence in just a few hours (about 2 hours). PCR consists of three steps:

1. Denaturing (at 96'C) the double-stranded DNA into single-stranded DNA.

2. Annealing of the primer (at 55-65 oC) to ssDNA (single standard).

3. Taq DNA polymerase. An enzyme isolated from Thermus aquaticus synthesised new strands (at 72 oC). An amplified gene is used to clone the desired gene. Advantage — Higher productivity, higher efficiency, reduced error proneness, and fewer human errors, cyclic and automated.

Key Points to Remember: Taq polymerase, primers, template DNA, and nucleotides are the key ingredients of PCR.

Solved Problems of Previous Year Questions

1. Plasmid vector in DNA recombinant technology means 

1. A virus that transfers genes to bacteria.

2. Extra-chromosomal autonomously replicating circular DNA.

3. Sticky end of DNA.

4. Any fragment of DNA carrying desirable gene.

Ans : (b) Extra-chromosomal autonomously replicating circular DNA

Plasmid is a genetic structure which is a small, circular ds RNA molecule that is distinct from a cell chromosomal DNA. We can get plasmids in bacterial cells. So they are extra chromosomal autonomously replicating circular DNA.

Tricks to Remember: The important features required to facilitate a vector cloning are sites for restriction endonuclease and its size and also a selectable marker- Origin of replication.

2. Which organism is used to transfer T-DNA?

1. Streptomyces hygroscopicus

2. Agrobacterium tumefaciens

3. Salmonella typhi

4. Escherichia coli

Ans: (b) Agrobacterium tumefaciens

Crown gall is caused by the causative agent Agrobacterium tumefaciens caused in many commercial crops. In recent years, it has been recognised that this disease is caused by the bacterium carrying the DNA plasmid or Ti plasmid and transferring it to the plant cells. By observing this relationship between the ti plasmid and crown gall, it has now been used widely in the genetic engineering as a vector, from transgenic plant to inject a novel gene in host plant.

Tricks to Remember: Agrobacterium tumefaciens-a naturally occurring soil microbe that causes crown gall disease in susceptible plants.

2. Match the following column I with column II. 

Ans : A-5, B-4, C-1, D-3, E-2

Practice Questions

1. How does plasmid differ from chromosomal DNA?

Ans:

Difference Between Plasmid DNA and Chromosomal DNA

Ans: In EcoRI, the cutting enzyme is called the restriction endonuclease enzyme. These express a special characteristic, that the  cuts of restriction enzymes produce the sticky ends which we refer as overhanging ends and it is very important in recombinant biotechnology.

These restriction endonuclease will cut between the the G and A (Guanine and Adenine) base pairs with more priority in EcoRI.

Conclusion

This article covers all important information according to the NEET syllabus. NEET aspirants can revise this document to score more marks in the NEET exams. This article covers all the important concepts and topics, questions from previous year NEET question papers. Try to solve the important questions on your own to test your memory and knowledge of this chapter.