11 Most VSAQ’s of Biotechnology : Principle and Processes Chapter in Inter 2nd Year Botany (TS/AP)

2 Marks

VSAQ-1 : Define biotechnology.

Biotechnology is a scientific discipline that involves the manipulation and utilization of living organisms, their cellular components, or biological processes to develop products and technologies for various applications. This interdisciplinary field spans genetics, molecular biology, microbiology, and other biological sciences to create valuable products, solve problems, and advance various industries, including agriculture, medicine, and environmental management. Biotechnology contributes to enhancing human welfare, healthcare, agriculture, and the environment through innovations and practical applications.

VSAQ-2 : What are molecular scissors? Where are they obtained from?

Molecular scissors, also known as restriction enzymes, are enzymes derived from bacteria. These enzymes possess the remarkable ability to cleave or cut DNA molecules at specific recognition sites. Restriction enzymes are a fundamental tool in genetic engineering and biotechnology because they enable scientists to perform precise DNA manipulation, such as cutting and splicing DNA sequences at specific locations. This ability is crucial for various applications, including gene cloning, recombinant DNA technology, and the creation of genetically modified organisms.

VSAQ-3 : Name any two artificially restricted plasmids.

  1. pBR322: Named after Bolivar and Rodriguez, who constructed it. It is widely used in molecular biology research.
  2. pUC19 and pUC101: Named after the University of California, where they were developed. These plasmids are commonly used as cloning vectors and for various molecular biology applications.

VSAQ-4 : What is EcoRI? How does it function?

EcoRI is a restriction enzyme isolated from the bacterium Escherichia coli. It functions by recognizing a specific palindromic DNA sequence, which is 5′-GAATTC-3′. When it encounters this sequence, EcoRI performs a precise cleavage between the G and the A, resulting in sticky ends on the DNA fragments. These sticky ends have complementary sequences and can anneal with complementary DNA fragments, enabling DNA recombination and cloning in biotechnology applications.

VSAQ-5 : What are cloning vectors? Given an example.

Cloning vectors are specialized DNA molecules employed to transport foreign DNA fragments into host organisms, often bacteria, where they can be replicated and multiplied. These vectors play a pivotal role in genetic engineering and biotechnology by facilitating the production of numerous copies of the inserted DNA. An example of a cloning vector is a plasmid, which is a small, circular piece of DNA commonly used for cloning purposes. Other examples of cloning vectors include bacteriophages like λ phage, cosmids, and artificial chromosomes such as BACs (Bacterial Artificial Chromosomes) and YACs (Yeast Artificial Chromosomes). These vectors enable the insertion and manipulation of DNA sequences in various biological applications.

VSAQ-6 : What is recombinant DNA?

Recombinant DNA refers to a DNA molecule that has been generated by combining DNA segments or genes from two different sources. This process involves the insertion of a specific gene or DNA fragment into a vector, such as a plasmid, using enzymes like DNA ligase to create a hybrid DNA molecule. Recombinant DNA technology is a cornerstone of genetic engineering and biotechnology, enabling scientists to manipulate and transfer specific genes or DNA sequences between organisms. It plays a pivotal role in the creation of genetically modified organisms (GMOs) with desired traits, as well as in various medical and industrial applications.

VSAQ-7 : What is palindromic sequence?

A palindromic sequence in DNA is a sequence of base pairs that exhibits a unique property. It reads the same when read in a specific direction on one DNA strand as it does when read in the opposite direction on the complementary DNA strand. In essence, it is a symmetrical sequence with respect to its central point.

VSAQ-8 : What is the full form of PCR? How is it useful in biotechnology?

PCR, which stands for Polymerase Chain Reaction, is a potent biotechnological tool used for the rapid amplification of a specific segment of DNA. Its applications in biotechnology are multifaceted:

  1. DNA Cloning: PCR facilitates the amplification of a targeted DNA fragment, allowing it to be inserted into a cloning vector. This cloned DNA can then be reproduced to generate multiple copies, a fundamental process in genetic engineering.
  2. Gene Amplification: With PCR, even minute DNA amounts can be substantially multiplied, proving invaluable in research and diagnostics where larger DNA quantities are necessary.
  3. DNA Fingerprinting: PCR is instrumental in DNA fingerprinting, where it amplifies specific DNA regions displaying individual variation. These unique DNA profiles are employed in the identification and comparison of individuals, playing crucial roles in fields like forensics and paternity testing.

VSAQ-9 : What is down-stream processing?

Downstream processing in biotechnology focuses on separation, purification, and isolation of desired products (e.g., proteins, pharmaceuticals) from complex mixtures generated during upstream processes. It ensures product purity, quality control, efficiency, and prepares products for commercialization and distribution. Techniques include filtration, centrifugation, chromatography, and crystallization.

VSAQ-10 : How does one visualize DNA on an agar gel.

Visualizing DNA on an agarose gel is a crucial technique in molecular biology. After DNA fragments have been separated by size through electrophoresis on the gel, researchers use a fluorescent dye, typically ethidium bromide, to stain the DNA. The gel, with the stained DNA fragments, is then placed under an ultraviolet (UV) light source. Under UV light, the ethidium bromide-bound DNA emits fluorescence, making the DNA bands visible. This technique enables scientists to analyze and determine the sizes of DNA fragments, facilitating various applications such as DNA fingerprinting, genetic analysis, and gene cloning. It provides valuable insights into DNA patterns and structures that would otherwise remain invisible to the naked eye.

VSAQ-11 : How can you differentiate between exonucleases and endonucleases?

Exonucleases cut nucleotides from DNA ends (3′ or 5′ exonuclease), while endonucleases cleave DNA at specific internal positions. Both are vital in processes like DNA repair and genetic engineering.