BIOLOGY 1 Marks Question

Meiosis I- Pachytene- When recombination nodule appear after synaptonemal complex formation.

Alien DNA must be linked to ori/origin of replication/site to start replication.

Bacteria: Lysozyme, fungi: chitinase.

Exonuclease: removes nucleotides from the ends of DNA molecules.
Endonuclease: makes cut at specific position within a DNA.

Gen for chain A and gene for chain B of insulin are prepared, inserted, into plasmid, of E.coli separately, E.coli cultured and chain extracted, combined by disulphide bonds (to produce human insulin).

(Gel) electrophoresis.

Plant cells.

Plant cells have cell wall made up of cellulose where as animal cell lack cell wall and do not contain cellulose. Therefore the enzyme cellulose is needed for isolating genetic material for plant cell only.

(Breaking the cell open) Treating with lysozyme.

Plasmids and bacteriophages.

PCR refers to Polymerase Chain Reaction. This technique was developed by Kary Mullis in 1985.

Lysozyme digests bacterial wall and chitinase digests fungal cell wall.

For bacteria- lysozyme.
For fungus- chitinase.

Tumour inducing plasmid of Agrobacterium tumefaciens is called Ti plasmid.

Salmonella typhimurium.

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

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

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

Ethidium bromide (EtBr) exchanges its visible range of wavelength with the invisible wavelength of DNA to make it visible under UV light.

The transformant loses ampicillin-resistance.

pBR322.

The transformant loses the tetracycline-resistance.

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

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.

Because they can be used in vitro to recognize and cut within specific DNA sequence typically consisting of 4-8 nucleotides.

Elution.

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

Rop.

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

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

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

Genetic engineering and sterilisation method.

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

Origin of replication (Ori).

DNA polymerase from Thermus aquaticus remains active during the high temperature induced denaturation of double stranded DNA.

By using Alkaline phosphatase enzymes.

Animal cells.

It is the source of thermostable DNA-polymerase enzyme.

K. Mullis.

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

To cut DNA at specific site.

Mg²⁺ is required as a cofactor for thermostable DNA polymerase.

Ethidium bromide.

 By spooling method.

Penicillin will kill the antibiotic sensitive E. coli cells.

rDNA - Recombinant DNA. cDNA-Complementary DNA.

E. coli and Saccharomyces cerevisiae.

Gelelectrophoresis.

Or

Gel electrophoresis is used to separate fragments of DNA cut by restriction endonucleases.

The main function of sampling port is to withdraw culture periodically.

Since plasmids can replicate within the bacterial cell independently of the genomic DNA, any alien DNA ligated to it well also multiply, i.e. It is used as a vector as well as in gene cloning.