Genetic Change In Bacteria Flashcards
Methods of genetic change in bacteria?
- Mutation
- Horizontal gene transfer
Horizontal transfer ?
Genetic information is passed from one living cell to another cell in the same generation e.g plasmid transfer
Mutation
A Change in the nucleotide sequence of DNA
May cause a change in the protein encoded by the gene
How do mutations occur
Spontaneous mutations
Induced mutations
Mutation can occur in;
No effect on the protein (remains functional)
Silent mutation
Missense mutation
A protein with different amino acid that may have an altered function
Nonsense mutation
Premature stop codon; incomplete condon ( turnicate) protein usually nonfunctional
Viruses that infect bacteria
Bacteriophage
Transducing particles
When new bacteriophage accidentally receives bacteria cell DNA when they’re being assembled instead of phage DNA
Obligate intracellular parasites (viruses )
Use host metabolic system and usually disrupt host normal cell function
Morphology(shapes) of viruses
Polyhedral- usually icosahedral shape with 20 triangular faces
Helical -long rod ;can be rigid and flexible
Envelope- Roughly spherical; dictated by lipid bilateral
Complex- polyhedral head with a helical tail ( only found bacteriophage)
Capsid structure of virus
Polyhedral
Helical
Naked virus enter cells via?
Endocytosis
Cell growth is controlled by two set of gene?
Proto oncogenes- gene that stimulates cell growth
Tumor suppressor gene- gene that inihibit cell growth
What is capsomere ?
The protein coat surrounding the nuclei acid, individual proteins coat is known as capsomere ( capsid in bulk)
