Biotechnology Principles and Processes Important Questions

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Very Short Answer Questions [1 Marks Questions]

Ques 1: What is recombinant DNA?

Ans 1. These are the molecules of DNA that are formed through a genetic recombination method.

Ques 2: What are Palindromes?

Ans 2. These are groups of letters that form the same words when you read it from the forward side and backward side. Ex: NITIN, MALAYALAM

Ques 3: What are the principles of Biotechnology?

Ans 3. There are two principles of Biotechnology i.e.:

1. Genetic engineering
2. Bioprocess engineering

Ques 4: What is the origin of replication in a chromosome?

Ans 4. In a chromosome there is a specific DNA sequence which is called origin of replication responsible for initiating replication.

Ques 5: What is the EFB in Biotechnology?

Ans 5. EFB stands for European Federation of Biotechnology (EFB) that is Europe’s non-profit federation of National Biotechnology Associations which are working to promote biotechnology throughout Europe and beyond.

Ques 6: What are cloning?

Ans 6. The ability of multiplying copies of antibiotic resistance genes in E.coli is called cloning.

Ques 7: What are the steps for modifying an organism?

Ans 7: The steps which are used to modify an organism are:

1. Recognition of DNA with desirable genes;
2. Introduction of the identified DNA into the host;
3. Maintenance of introduced DNA in the host and transfer of the DNA

to its source.

Ques 8: Which enzymes are used for treating bacterial cells/plant or animal tissue?

Ans 8: The enzymes which are used to treat bacterial cells/plant or animal tissue are:

1. Lysozyme (bacteria)
2. Cellulase (plant cells)
3. Chitinase (fungus)

Ques 9: What is Genetic engineering?

Ans 9: It is a technique which is used to alter the chemistry of genetic material (DNA and RNA), to introduce these into host organisms and change the host organism.

Ques 10: What is the meaning of “Eco”, “R” and “I” in the enzyme EcoRI?

Ans 10: EcoRI comes from Escherichia coli RY 13 and the letter ‘R’ is derived from the name of strain.

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Short Answer Questions [2 Marks Questions]

Ques 1: What are the tools required to perform genetic engineering or recombinant DNA technology?

Ans 1: The tools required to perform genetic engineering can be accomplished by:

1. Restriction
2. Polymerase
3. Ligases
4. Vectors
5. Host organism

Ques 2: What is the difference between exonucleases and endonucleases?

Ans 2: Restriction enzymes belong to a larger class of enzymes called nucleases. There are two kinds of nucleases i.e.:

1. Exonucleases: It removes nucleotides from the ends of the DNA.
2. Endonucleases: It makes cuts at specific positions within the DNA.

Ques 3: Why ethidium bromide is used for staining the DNA?

Ans 3: The separated DNA fragments that can be visualised by staining the DNA with a compound known as ethidium bromide followed by exposure to UV. In case of elution where the separated bands of DNA are cut out from the agarose gel and extracted from the gel piece.

Ques 4: What are the features that are required to facilitate cloning into a vector?

Ans4: The features that is required to facilitate cloning into a vector are:

1. Origin of replication (ori): It is a sequence from where replication starts and any piece of DNA when linked to this sequence and be made to replicate within host cells.
2. Selectable marker: It helps in identifying and eliminating non-transformants and selectively permitting the growth of the transformants.
3. Cloning sites: The presence of more than one recognition sites within the vector will generate several fragments, which will complete the gene cloning.
4. Vectors for cloning genes in plants and animals: Now transferring genes into plants and animals from bacteria and viruses is possible. Ex: transform normal plant cells into a tumour and direct these tumour cells to produce the chemicals required by the pathogen. In the same way, retroviruses in animals have the ability to transform normal cells into cancerous cells.

Ques 5: What is the meaning of PCR (Polymerase Chan Reaction)?

Ans 5: The multiple copies of the gene (or DNA) of interest are synthesised in vitro using two sets of primers (small chemically synthesised oligonucleotides that are complementary to the regions of DNA) and the enzyme DNA polymerase.

Each cycle has three steps:

1. Denaturation
2. Primer annealing
3. Extension of primers

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Long Answer Questions [3 Marks Questions]

Ques 1: What is the difference between Plasmid and chromosomal DNA?

Ans 1: The difference between Plasmid and Chromosomal DNA is:

Ques 2: Write any two properties of restriction endonuclease enzymes?

Ans 2: The properties of restriction endonuclease enzyme are:

1. Restriction enzymes cut DNA at specific sequences called recognition sequences or sites.
2. Restriction endonuclease recognises specific palindromic sequence and forms sticky ends on each strand, which facilitates joining by DNA ligase.
3. Its function is to cut the sugar-phosphate backbone at specific sites.

Ques 3: The following proteins of given molecular weight are Subjected to Get electrophoresis. Write the order of Sequence in which these proteins are isolated in a gel?

Ans 3:

The sequence of proteins obtained from top to bottom in a gel:

Myosin > Insulin >Haemoglobin> Ribozyme > Keratin > Albumin.

Ques 4: What are the properties of a good vector?

Ans 4: The properties for a good vector are:

1. The vector must be of same size so that it can isolate and purify.
2. There should be a replication, as base pair sequence from where replication starts.
3. There should be a selectable marker that helps in selecting the transformed host cells.
4. The vector should have at least one unique recognition site to bind the foreign DNA.

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Very Long Answer Questions [5 Marks Questions]

Ques 1: Identify the figure given below: 

Ans 1: Part A is labelled as Plasmid while part B is labelled as Nucleoid

Ques 2: Name the regions A, B, and C?

Ans 2: A. Sa1 I

B- Pvu II

C- tetR (tetracycline or kanamycin)

Ques 3: What is Bioreactor and the advantages of Stirred tank Bioreactor over Shake flask?

Ans 3: Bioreactors are the devices which are in the form of a vessel that contains various organisms or chemical substances. In this vessel raw materials are biologically converted into specific products, individual enzymes, etc., using microbial plant, animal or human cells. A bioreactor provides the optimal conditions for achieving the desired product by providing optimum growth conditions (temperature, pH, substrate, salts, vitamins, oxygen). The most commonly used bioreactors are of stirring type. A stirred-tank reactor is usually cylindrical or with a curved base to facilitate the mixing of the reactor contents.

The advantages of Bioreactor over shake flask are:

1. To produce the optimum growth of the desired product, it provides the optimal conditions e.g., temp, pH, etc.
2. For testing the sample, a small volume of cultures can be withdrawn periodically from the bioreactor.
3. It has an agitation system, temp control system, from control system & pH control system.

Ques 4: Identify the steps A, B, C in the following diagram?

Ans 4: A- Denaturation– The DNA strands are treated with a temperature 94 and the strands are separated.

B- Annealing– The primers anneal to the complementary strands.

C- Extension– The DNA polymerase facilitates the extension of the strands.

Ques 5: What is PCR, and what are the different steps involved in this technique?

Ans 5: PCR stands for Polymerase Chain Reaction; it is a method of making millions of DNA copies from a DNA sample. It has multiple copies of the gene (or DNA) of interest synthesised in vitro using two sets of primers.

There are two reagents i.e.:

1. Primers: It is a short single-stranded DNA fragment that is a complementary sequence to the target DNA.
2. DNA polymers: It is heat stable, that is TAQ polymerase that is extracted from the bacteria Thermus aquaticus.

There are three steps:

a) DENATURATION: It is the 1st step where; the two strands of the DNA helix are physically separated at a heat during a process called macromolecule denaturation.

b) RENATURATION / ANNEALING: It is the 2nd step, where the temperature is lowered so that the primers can bind to the complementary sequences of DNA.

c) EXTENSION: It is the 3rd step where the target DNA sequence will synthesize its copies by the process of the extension of the primers.

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Previous Year Questions

• Some of the steps involved in the production of Humulin are given below… (Karnataka Common Entrance Test)
• First cloned animal… (National Eligibility Cum Entrance Test)
• First discovered restriction endonuclease that always cuts DNA… (National Eligibility Cum Entrance Test)
• Plasmid has been used as vector because… (NEET 2000)
• Choose the correct pair from the following… (NEET 2020)
• Introduction of food plants developed by genetic engineering is not desirable because… (NEET 2002)
• A gene whose expression helps to identify transformed cell is known as… (NEET 2017)
• Two microbes found to be very useful in genetic engineering are… (NEET 2006)
• A selectable marker is used to… (NEET 2019)
• Commonly used vectors for human genome sequencing are… (NEET 2014)
• Biolistics (gene-gun) is suitable for… (NEET 2012)
• Agarose extracted from sea weeds finds used in… (NEET 2011)
• Match the organism with its use in biotechnology… (NEET 2020)
• During the process of isolation of DNA, chilled ethanol is added to… (NEET 2013)
• DNA fragments are… (NEET 2017)

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