Animal Biotechnology 2019
- Answer any ten questions from the following:
a) What do you mean by genomics?
Ans→ Genomics is a subject of biology that deals with the study of the structures, function, mapping, editing of complete set of genome (DNA and RNA) of organisms.
b) What are the full forms of BAC and MAC?
Ans→ BAC: Bacterial Artificial Chromosome
MAC: Mammalian Artificial Chromosome
c) What is a “Sticky end”?
Ans→ Sticky end is a single stranded overhang at the end of a DNA molecule formed by restriction enzymes used in genetic engineering techniques.
d) From which organism Taq polymerase is isolated?
Ans→ A heat stable DNA polymerase known as Taq polymerase is isolated from thermophilic bacterium Thermus aquaticus.
e) What kind of blot is used to detect RNA?
Ans→ Northern blot is used to detect RNA.
f) Who proposed the dideoxy method of DNA sequencing?
Ans→ Laureate Federic Sanger in 1977 proposed the dideoxy method of DNA sequencing. Hence the other name is Sanger sequencing.
g) What do you mean by gene knockout?
Ans→ Gene knockout Is a genetic technique that involves disabling or removing a specific gene from an organism to study of its function or effects of its absence.
h) What is a chimera?
Ans→ Chimera is an organism composed of at least two different sets of DNA resulting from their fusion of different zygotes or embryos.
i) Define expression vector.
Ans→ Expression vectors are the vectors that are designed for gene expression in cells to determine the successful cloning process.
j) Name two blocking agents in Western blot.
Ans→ Bovine Serum Albumin (BSA) , Steelhead Salmon Serum.
k) What is the function of a probe?
Ans→ Probe is used to search its complementary sequence in the sample genome.
l) What do you mean by a thermocycler?
Ans→ Thermocycler is a laboratory apparatus that facilitates the amplification of DNA segments by regulating at different temperatures.
m) Primer annealing is an integral part of which technique?
Ans→ Polymerase Chain Reaction (PCR)
n) RNA dependent DNA polymerase is also known as
Ans→ Reverse Transcriptase.
o) What do you mean by R factors?
Ans→ R factor is a group of genes in some bacteria that provide a resistance for antibiotics that is transferred from cells to cells through conjugation.
- Answer any five questions from the following:
a) Between PVDF and nitrocellulose membrane which one is superior and why?
Ans→ PVDF is superior to nitrocellulose for most applications because it has higher protein-binding capacity, better mechanical durability, and is hydrophobic, making it ideal for re-probing and long-term storage. Nitrocellulose, though cheaper and easier to handle, is fragile and less stable.
b) Write down two applications of DNA microarray.
Ans→ (i) Gene expression Profiling: DNA microarray widely used to measure the expression level of thousands of genes simultaneously.
(ii) Genomic DNA CNV Analysis: DNA micro arrays can be used to detect genomic DNA copy number variation.
c) Differentiate blind cut and staggered cut using suitable examples.
Ans→ Blind cut: A blind cut is a restriction enzyme cut that leaves no overhangs, resulting in blunt-ended DNA fragments.
For example: The enzyme SmaI cuts the sequence 5’-CCC▼GGG-3’, producing:
5’-CCC GGG-3’
3’-GGG CCC-5’
Staggered Cut: A staggered cut is a restriction enzyme cut that leaves overhangs, producing “sticky” ends.
For example: The enzyme EcoRI cuts the sequence 5’-G▼AATTC-3’, producing:
5’-G AATTC-3’
3’-CTTAA G-5’
d) Describe any two uses of gene cloning.
Ans→ (i) Recombinant protein production: Gene cloning allows cloned cells to produce large quantities of encoded protein (Human insulin).
(i) Vaccines: To produce live recombinant vaccine.
e) What is the significance of using ddNTPs in the Sanger method of DNA sequencing?
Ans→ ddNTPs are used in the Sanger method to terminate DNA synthesis at specific bases, as they lack a 3′-OH group. This creates DNA fragments of different lengths, which are then used to determine the sequence of the template DNA.
f) What is the utility of colony hybridization experiment?
Ans→ (i) Identification: Enables the identification of bacterial colonies containing specific DNA sequences of interest.
(ii) Screening libraries: Useful for screening large gene libraries to find clones carrying genes or sequences.
(iii) Isolation of clones: Allows the isolation of clones Carrying the specific genes or DNA fragments for further analysis.
g) What is the role of alkaline phosphatase in Western blotting?
Ans→ (i) It is used as a secondary antibody conjugate in the detection step
(ii) Alkaline phosphatase catalyzes a reaction with substrate into a coloured or chemiluminescent product.
h) How do you differentiate colony hybridization and plaque hybridization?
Ans→ Colony hybridization involves the identification of specific DNA sequences In a bacterial colony by hybridizing a level probe to the Target DNA
Procedure: After bacterial colonies Are transferred to a membrane the membrane is treated with a label DNA probe that binds to complementary sequences.
Animal biotechnology 2020
1) Answer any ten questions from the following:
a) What do you mean by GMOs?
Ans→ Genetically modified organisms GMOs are the plants, animals or microbes whose genetic material has been altered by using genetic engineering techniques for specific desired traits.
b) What is “molecular pharming”?
Ans→ Molecular farming is the use of genetically modified plants or animals to produce pharmaceutically important and commercially valuable protein for medical purposes.
c)What is ‘electroporation’?
Ans→ Electroportation is a technique in which an electric field is applied to cells in order to increase the permeability of the cell membrane to allow the DNA into the cytoplasm of the cell.
d) What is ‘chromosome painting’?
Ans→ Chromosome painting is a technique that uses fluorescent labelled probes to identify several gene sequences simultaneously in a chromosome.
e) Name two proteins that can be produced in the milk of domestic animals.
Ans→ Insulin and Human growth hormone (hGH)
f) What is ‘probe’?
Ans→ Probe is a single stranded sequence of DNA used to search for its complementary sequence in the sample genome.
g) What is the usage of ‘liposome’?
Ans→ Liposomes are utilised in various biotechnological applications such as delivery of enzymes, delivery of genetic material or other bioactive compounds.
h) What is zooblot?
Ans→ Zooblot is a type of Southern blood that demonstrates the similarity between specific, usually protein coding DNA sequences of different species.
i) Mention the function of ethidium bromide.
Ans→ (i) Commonly used for staining nucleic acid such as DNA and RNA.
(ii) Its primary function is to intercalate between the base pairs of DNA causing the DNA to fluorescence When exposed to UV light.
j) What do you mean by in vitro cell culture?
Ans→ In vitro cell culture involves growing and maintaining cells outside their natural environment performed in laboratory in controll way.
k) Who formulated the concept of PCR?
Ans→ The concept of PCR (Polymerase Chain Reaction) was formulated by Kary B. Mullis in 1983.
l) What is ‘pallindromic sequence’?
Ans→ A palindromic sequence in DNA is a sequence of bases that reads the same in the 5′ to 3′ direction on both strands. Example: 5′-GAATTC-3′ and 3′-CTTAAG-5′.
m) Name any one viral vector that is used in cloning experiments.
Ans→ Simian virus 40 (SV 40), Retrovirus, Adenovirus
n) What is VNTR?
Ans→ Variable number of tandem repeats (VNTR) representing short, repeating DNA sequences that vary in the number of repeats among individuals.
o) Name any two restriction endonucleases.
Ans→ Eco RI and Hind III
2) Answer any five questions from the following:
a) Write down the advantages of BACs over YACS.
Ans→ (i) BACs are known for their stability in a bacteria cell allowing for their reliable maintenance of large DNA inserts
(ii) BACs are relatively easy to manipulate and propagate in a bacterial system simplifying the cloning process.
(iii) BACs are commonly used to construct genomic libraries enabling the study of entire genomes.
YACs
(i) YACs have a high capacity for carrying large DNA fragments making them ideal for cloning.
(ii) Replicates in the yeast provide eukaryotic environments.
(iii) YACs exhibit mitotic stability in yeast cell.
b) What do you mean by gene redundancy?
Ans→ Gene redundancy refers to the presence of multiple genes in the genome of an organism that performs similar or overlapping function.
Example: Gene redundancy seen in haemoglobin genes
c) What is the utility of “gene knockin”?
Ans→ Gene knockin is used to introduce specific genetic modifications into an organism’s genome to study gene function, model human diseases, or produce desired traits. It is valuable in biomedical research and therapeutic development.
d) How do you differentiate primary cell culture from sub culture?
Ans→Primary Cell Culture
1) Derived directly from tissues or organs.
2) Cells are freshly isolated and exhibit characteristics similar to their tissue of origin.
3) Limited lifespan and heterogeneous.
Subculture
1) Derived from passaging primary cells into new culture vessels.
2) Cells adapt to in vitro conditions and may become more homogeneous.
3) Prolongs cell lifespan but may lead to phenotypic changes over time.
e) Why dideoxy sequencing method is advantageous over Maxam-Gilbert method of nucleotide sequencing?
Ans→ The dideoxy sequencing method (Sanger method) is advantageous over the Maxam-Gilbert method because it is simpler, safer, and requires less specialized equipment. It also involves fewer steps and uses radioactive labeling, making it more widely accessible and easier to automate.
f) Differentiate type I and type II restriction endonucleases.
Ans→
| Type I Restriction Endonucleases | Type II Restriction Endonucleases | |
| Function | Recognize specific DNA sequences but cleave DNA at random sites, far from the recognition site. | Recognize specific DNA sequences and cut at or near the recognition site. |
| Requirement | Require ATP. | Do not require ATP. |
| Cleavage | Produce fragments of variable lengths. | Produce defined, predictable fragment sizes |
| Example | EcoKI | EcoRI |
g) Write down two uses of cell culture.
Ans→1) Drug Testing and Development: Cell cultures are used to test the efficacy and toxicity of new drugs.
2) Gene Therapy: Used for the production of therapeutic proteins and to study gene function or mutations.
h) Differentiate between blunt ends and sticky ends.
Ans→
| Blunt Ends | Sticky Ends | |
| Definition | DNA fragments with straight, even ends after enzyme cleavage. | DNA fragments with overhanging, single-stranded ends after enzyme cleavage. |
| Formation | Created by restriction enzymes that cut straight across both DNA strands. | Created by restriction enzymes that cut at staggered positions on the two strands. |
| Ligating | Less efficient, as they require exact matching of the ends. | More efficient due to complementary base pairing between overhangs. |
| Example | SmaI enzyme. | EcoRI enzyme |
Animal biotechnology 2021
1) Answer any ten questions from the following:
a) What is Phasmid?
Ans→ A phasmid is a type of hybrid plasmid that contains a bacteriophage (virus) genome. It combines features of both plasmids and bacteriophages, often used in genetic research and cloning.
b) What is RT-PCR?
Ans→ Reverse transcription polymerase chain reaction (RT-PCR) is a laboratory technique combining reverse transcription of RNA to DNA and amplification of a specific DNA target using polymerase chain reaction.
c) What is the difference between the cDNA library and the genome library?
Ans→
| cDNA Library | ||
| Source | Composed of complementary DNA (cDNA) synthesized from mRNA. | Composed of DNA fragments from the entire genome, including both coding and non-coding regions. |
| Representation | Represents only the expressed genes (exons). | Represents the complete genetic material of an organism. |
| Purpose | Used to study gene expression and protein-coding sequences. | Used for mapping genomes and studying all genetic elements. |
| Size | Smaller compared to genome libraries, as it only includes genes that are transcribed. | Larger, as it includes the entire genomic content. |
cDNA Library
Source: Composed of complementary DNA (cDNA) synthesized from mRNA.
Representation: Represents only the expressed genes (exons).
Purpose: Used to study gene expression and protein-coding sequences.
Size: Smaller compared to genome libraries, as it only includes genes that are transcribed.
Genome Library
Source: Composed of DNA fragments from the entire genome, including both coding and non-coding regions.
Representation: Represents the complete genetic material of an organism, including introns, exons, and regulatory regions.
Purpose: Used for mapping genomes and studying all genetic elements.
Size: Larger, as it includes the entire genomic content.
d) Write the advantage of nylon membrane over nitrocellulose membrane in Southern Blotting.
Ans→ The nylon membrane in Southern blotting has a higher binding capacity for DNA, better durability, and is more resistant to alkaline conditions, making it more reliable than nitrocellulose for long-term storage and re-probing.
e) From which organism Taq polymerase is isolated?
Ans→ A heat stable DNA polymerase known as Taq polymerase is isolated from thermophilic bacterium Thermus aquaticus.
f)What do you mean by gene knockout?
Ans→ Gene knockout Is a genetic technique that involves disabling or removing a specific gene from an organism to study of its function or effects of its absence.
g) Name two blocking agents in Western blot.
Ans→ Bovine Serum Albumin (BSA) , Steelhead Salmon Serum.
h) What do you mean by R factor?
Ans→ R factor is a group of genes in some bacteria that provides a resistance for antibiotics that is transferred from cells to cells through conjugation.
i) What is VNTR?
Ans→ Variable number of tandem repeats (VNTR) representing short, repeating DNA sequences that vary in the number of repeats among individuals.
j) What is RFLP?
Ans→ Restriction Fragment Length Polymorphism (RFLP) is a genetic variation caused by differences in DNA sequence recognised by restriction enzymes.
k) What is biolistics?
Ans→ BioListics or biological ballistics is a biotechnological method to introduce DNA or RNA into sales through highly accelerated microscopic particles.
l) What is YAC?
Ans→ Yeast Artificial Chromosome (YAC) is a human engineered DNA molecule used to insert large DNA fragments and clone in yeast cell.
m) Why ddNTPs are used in Sangers method?
Ans→ ddNTPs are used to terminate further elongation of DNA results in a set of DNA fragments of varying length and can be determined by analysing the position of the terminated fragments.
n) Why serum is used in culture media?
Ans→ Serum is used as a source of essential nutrients, growth factors and hormones that support the growth and viability of cells in cell culture.
o) Which type of cell is Hela?
Ans→ Hela cells are types of immortal cells that they can divide indefinitely in cell culture. These cells are derived from Henrietta Lacks in 1951.
2) Answer any five questions from the following:
a) Mention two differences between BAC and MAC.
Ans→
| BAC | MAC | |
| 1) Vector Type | Used for cloning large DNA fragments (100-300 kb). | Designed for cloning very large DNA fragments (up to several megabases). |
| 2) Host | Typically inserted into E. coli for replication and maintenance. | Introduced into mammalian cells for replication and gene |
b) Write down two application of DNA microarray.
Ans→ (i) Gene expression Profiling: DNA microarray widely used to measure the expression level of thousands of genes simultaneously.
(ii) Genomic DNA CNV Analysis: DNA micro arrays can be used to detect genomic DNA copy number variation.
c) Write two application of transgenic animals.
Ans→ (i) Pharmaceutical Production: Transgenic animals are used to produce therapeutic proteins, such as insulin or clotting factors.
(ii) Disease Models: They are used to study human diseases, allowing for better understanding and development of treatments.
d) What is plaque hybridization?
Ans→ Plaque hybridization is a technique used to detect specific DNA sequences within a collection of phage plaques. It involves transferring DNA from the plaques onto a membrane, then probing with a labeled DNA or RNA probe to identify the presence of the target sequence.
e) What is the cos site in phage? Write the advantages of cosmid as a vector.
Ans→ The cos site in a phage is a short, cohesive DNA sequence that allows the phage genome to circularize after infection.
Advantages of cosmid vectors:
Large Insert Capacity: Can carry DNA fragments up to 40-50 kb, larger than plasmids.
Efficient Cloning: Combines features of both plasmids and phages, allowing efficient DNA packaging and stable maintenance in host cells.
f) What are the main characteristics of cloning bacteria?
Ans→ The main characteristics of cloning bacteria are: (i) Rapid Growth (ii) Antibiotic Resistance (iii) Easy to Transform (iv) Stable Maintenance.
g) How staggered end is transformed into sticky end?
Ans→ A staggered end refers to the uneven cutting of DNA by a restriction enzyme, creating sticky ends (single-stranded overhangs) that can form hydrogen bonds with complementary sequences in other DNA molecules. The sticky ends can then be ligated to another DNA fragment with complementary overhangs.
h) What do you mean by a Probe? What is its role in gene cloning?
Ans→ A probe is a short, labeled sequence of nucleic acid (DNA or RNA) used to detect the presence of a complementary sequence in a sample.
In gene cloning, a probe is used to identify and isolate specific DNA fragments that contain the gene of interest.
Animal biotechnology 2023
1) Answer any ten questions from the following:
a) What is chromosome painting?
Ans→ Chromosome painting is a technique that uses fluorescent labelled probes to identify several gene sequences simultaneously in a chromosome.
b) Name any two restriction endonucleases.
Ans→ EcoRI and Hind III
c) What is zooblot?
Ans→ Zooblot is a type of Southern blood that demonstrates the similarity between specific, usually protein coding DNA sequences of different species.
d) Name any two viral vectors that are used in cloning experiment.
Ans→ Simian virus 40 (SV 40), Retrovirus, Adenovirus
e) What is the usage of liposome?
Ans→ Liposomes are utilised in various biotechnological applications such as delivery of enzymes, delivery of genetic material or other bioactive compounds.
f) What is palindromic sequence?
Ans→ A palindromic sequence in DNA is a sequence of bases that reads the same in the 5′ to 3′ direction on both strands. Example: 5′-GAATTC-3′ and 3′-CTTAAG-5′.
g) What do you mean by GMOs?
Ans→ Genetically modified organisms GMOs are the plants, animals or microbes whose genetic material has been altered by using genetic engineering techniques for a specific desired traits.
h) Mention the function of ethidium bromide.
Ans→ (i) Commonly used for staining nucleic acid such as DNA and RNA.
(ii) Its primary function is to intercalate between the base pairs of DNA causing the DNA to fluorescence When exposed to UV light.
i) Primer annealing is an integral part of which technique?
Ans→ Polymerase Chain Reaction (PCR)
j) What are the full forms of BAC and MAC?
Ans→ BAC: Bacterial Artificial Chromosome
MAC: Mammalian Artificial Chromosome
k) What kind of blot is used to detect RNA?
Ans→ Northern blot is used to detect RNA.
l) What is a sticky end?
Ans→ Sticky end is a single stranded overhang at the end of a DNA molecule formed by restriction enzymes used in genetic engineering techniques.
m) What is probe?
Ans→ Probe is a single stranded sequence of DNA used to search of its complementary sequence in a sample genome.
n) From which organism Taq polymerase is isolated?
Ans→ A heat stable DNA polymerase known as Taq polymerase is isolated from thermophilic bacterium Thermus aquaticus.
o) What is chimera?
Ans→ Chimera is an organism composed of at least two different set of DNA resulting from their fusion of different zygotes or embryos.
2) Answer any five questions from the following:
a) What is the role of alkaline phosphatase in western blotting?
Ans→ (i) It is used as a secondary antibody conjugate in the detection step
(ii) Alkaline phosphatase catalyzes a reaction with substrate into a coloured or chemiluminescent product.
b) How do you differentiate colony hybridization experiment?
Ans→ Colony hybridization involves the identification of specific DNA sequences In a bacterial colony by hybridizing a level probe to the Target DNA
Procedure: After bacterial colonies Are transferred to a membrane the membrane is treated with a label DNA probe that binds to complementary sequences.
c) Between PVDF and nitrocellulose membrane which one is superior and why?
Ans→ PVDF is superior to nitrocellulose for most applications because it has higher protein-binding capacity, better mechanical durability, and is hydrophobic, making it ideal for re-probing and long-term storage. Nitrocellulose, though cheaper and easier to handle, is fragile and less stable.
d) What is the utility of colony hybridization experiment?
Ans→(i) Identification: Enables the identification of bacterial colonies containing specific DNA sequences of interest.
(ii) Screening libraries: Useful for screening large gene libraries to find clones carrying genes or sequences.
(iii) Isolation of clones: Allows the isolation of clones Carrying the specific genes or DNA fragments for further analysis.
e) What is the utility of gene knockin?
Ans→ Gene knockin is used to introduce specific genetic modifications into an organism’s genome to study gene function, model human diseases, or produce desired traits. It is valuable in biomedical research and therapeutic development.
f) Differentiate type I and type II restriction endonucleases.
Ans→
| Type I Restriction Endonucleases | Type II Restriction Endonucleases | |
| Function | Recognize specific DNA sequences but cleave DNA at random sites, far from the recognition site. | Recognize specific DNA sequences and cut at or near the recognition site. |
| Requirement | Require ATP. | Do not require ATP. |
| Cleavage | Produce fragments of variable lengths. | Produce defined, predictable fragment sizes |
| Example | EcoKI | EcoRI |
g) What is Expression vector? Give an example.
Ans→ Expression vectors are the vectors that are designed for gene expression in cells to determine the successful cloning process.
Example: pET- 28a (+), pGEX- 4T, pBAD
h) What is Totipotency?
Ans→ Totipotency refers to the ability of a single cell to give rise to all the different cell types of an organism including both embryonic and extra-embaronic tissues.