Biology 1 Marks Question

Salmonella typhimurium.

Genetic engineering and sterilisation method.

Hind II (From Haemophilus influenzae bacterium)

Normal Endonuclease makes cuts at random positions within a DNA sequence. Restriction endonuclease makes cuts only at specific positions within a DNA sequence.

In case ofligation at sal I site, the transformant loses the tetracycline resistance while, in case of pvu I, the transformant loses ampicillin resistance.

They act as molecular scissors to cut DNA at specific locations.

Bacteriophages are used as vectors because of very high copy number of their genome within the bacterial cells. Also they have the ability to gain an easy entry into the bacterial hosts in order to produce large number of recombinant DNA.

The DNA fragments are negatively charged so they move towards the positively charged anode.

European Federation of Biotechnology.

Due to the presence of cell wall in plants, cellulase is used, whereas the animal cell lacks cell wall.

1. cDNA: Complementary DNA.
2. Bt: Bacillus thuringiensis.

Plasmids and bacteriophages.

In the absence of a selectable marker, it will not be possible to identify the recombinants from the non recombinants.

Retroviruses are disarmed (diseases-causing gene is removed/ inactivated) and used as vectors to deliver the recombinant/ alien DNA into animal cells.

In eukaryotes, normal endonuclease attach with special proteins, like initiator/ terminator, to perform their functions.

rDNA- Recombinant DNA.
BACs- Bacterial Artificial Chromosomes.
YACs- Yeast Artificial Chromosomes.

Palindromes are group of letters (sequences) that read same both in forward and backward direction.

Elution.

pBR322.

The gel is stained by ethidium bromide, to view the separated DNA bands when exposed to UV light.

Rop.

The DNA molecule that carry a foreign gene segment and replicate inside host cell is called vector.

Biotechnology is the technological employment of living organisms (especially micro-organisms) to produce the materials for human uses.

DNA ligase.

A plasmid is a circular extra-chromosomal DNA molecule present in a bacterial cell, which replicates autonomously, of the bacterial chromosomal DNA.

A higher number of copies of plasmid vector helps in producing a large quantity of recombinant protein.

Ethidium bromide.

It helps in identifying the recombinants from the non recombinants.

When it infects a plant cell, it delivers a part of its DNA, called T-DNA for Tumour inducing (Ti plasmid) into the plant cell and transforms it into a tumour cell.

rDNA - Recombinant DNA. cDNA-Complementary DNA.

The European Federation of Biotechnology defines biotechnology as the integration of natural science and organisms, cells or parts thereof and molecular analogues, for products and services; it encompasses both traditional and modern molecular biology.

First restriction endonucleases Hizd II was discovered by Smith Wilcox and Kelley in 1968.

Agarose.

Origin of replication (ori).

Competent host organism. The product is called recombinant molecule.

Electrophoresis was developed by Tiselius in 1937 and is based on the principle that charged particles move under the influence of electric current to oppositely charged electrodes.

Genetic engineering.

Endonuclease.

R stands for RY 13, the strain of E.coli bacterium.

DNA is a hydrophilic molecule; hence it cannot enter through plasma membrane.

Rerstriction enzymes.

Thermus aquaticus.

The transformant loses ampicillin-resistance.

The transformant loses the tetracycline-resistance.

Protease is added because it helps in digesting proteins and helps in the breakdown of cell wall by dissolving it.

To cut DNA at specific site.

Agarose; it provides the sieving effect for the DNA to resolve according to their size.

Recombinant DNA is the DNA formed by combining DNAs from two different organisms.

Agrobacterium tumefaciens.