What is genetic fine structure?

Genes: Properties, Classification and Fine Structure | Genetics.

Who gave the fine structure of gene?

1866 G.J. MENDEL A unit factor that controls specific phenotypic trait
1902 SIR A.E.GARROD One gene –one metabolic block theory
1940 BEADLE & TATUM One gene-one enzyme theory

What is the characteristic feature of r mutant of T4 bacteriophage used in benzer’s experiment?

The experiments of Benzer using mutants defective in the T4 rII system, during 1955-1959, showed that individual genes have a simple linear structure and are likely to be equivalent to a linear section of DNA (see also Phage group).

What is bacteriophage genetics?

Bacteriophages have played and continue to play a key role in bacterial genetics and molecular biology. Historically, they were used to define gene structure and gene regulation. Also the first genome to be sequenced was a bacteriophage.

What is fine structure analysis?

Fine structure genetics encompasses a set of tools used to examine not just the mutations within an entire genome, but can be isolated to either specific pathways or regions of the genome. Ultimately, this more focused lens can lead to a more nuanced and interactive view of the function of a gene.

What are the properties of genetic code?

Properties of Genetic Code:

  • Code is a Triplet:
  • The Code is Degenerate:
  • The Code is Non-overlapping:
  • The Code is Comma Less:
  • The Code is Unambiguous:
  • The Code is Universal:
  • Co-linearity:
  • Gene-polypeptide Parity:

Which of the following terms are described in Benzer’s concept of gene?

Benzer, in view of his work, coined the terms cistron (unit of function), recon (unit of recombination) and muton (unit of mutation).

What type of mutation was detected in a mutant of T4 phage?

These mutations, designated amber (am), are conditional lethals in the sense that they form plaques on Escherichia coli strain CR63, but not on strain B. Wild-type bacteriophage form plaques on both strains. We will show that these mutations are widely distributed in the genome of T4.

Which part of the bacteriophage is the genetic material?

Characteristics of bacteriophages Like all viruses, phages are simple organisms that consist of a core of genetic material (nucleic acid) surrounded by a protein capsid. The nucleic acid may be either DNA or RNA and may be double-stranded or single-stranded.

How are bacteriophages genetically modified?

In a standard procedure, the plasmid containing a designed mutation flanked by homologous sequences of phage is constructed and transformed into host bacteria, which is then infected with the phage to be engineered (Figure 1B). The resulted recombinant phages containing the desired mutations were then screened.

What is fine structure in Spectra?

fine structure, in spectroscopy, the splitting of the main spectral lines of an atom into two or more components, each representing a slightly different wavelength. Fine structure is produced when an atom emits light in making the transition from one energy state to another.

How does a phage reproduce in a bacteria?

The phage genome replicates as a prophage in the bacterial cell. In most lysogenic bacteria the genes required for lytic phage development are repressed and the production of infectious phage does not occur. Lambda phages attach to bacterial cells and insert their linear DNA into the bacterial cytoplasm.

What is the structure of bacteriophage T4?

For example, bacteriophage T4 of Escherichia coli has an icosahedral head structure made of repeat protein sub-units known as the capsid. This head structure contains a linear double-stranded viral genome. Phage genome varies in size from approximately 2 to 200 kilobases per strand of nucleic acid.

What is the difference between transduction and integration in phages?

During integration into host genes, the phage loses genes required for replication, this prevents the induction of the lytic cycle and killing of host bacteria. Transduction is the process by which the DNA is mobilized between cell by a virus.

What is the difference between a temperate and virulent phage?

Virulent (lytic phage): Virulent phage replicate in the susceptible bacteria producing many copies of themselves and destroys the host cells in the process by lysis. e.g. T-even; T2 and T4 phages of E. coli. Temperate phages: Infection by temperate phages can have either of two outcomes.