Microbial Genetics (Lec. 6) Flashcards
Define genetics
study of genes
Define genome
the complete set of genes or genetic material in an organism
Define chromosome
Condensed genetic material (DNA and proteins)
Define gene
an area of a chromosome that codes for a specific protein
Define genetic code
All the nucleotides in your genome
Define genotype
your genes (not the physical manifestation)
Define phenotype
the physical expression of your genes
Define genomics
the study of an organism’s entire genome
Describe how DNA serves as genetic information for all organisms except RNA viruses
It’s used a template to code for proteins, but RNA viruses don’t have DNA
Describe the function of plasmids
Circular units of self-replicating DNA that can insert themselves into bacterial genomes
Describe the function of transposons
segments of DNA that can bind to transposase, which will move a gene around
Differentiate horizontal and vertical gene transfer
Vertical gene transfer: cell division
Horizontal gene transfer: the transfer of DNA among members of the same generation
Describe the three mechanisms of HGT in bacteria
Conjugation: the donor cell (F+) has a sex pilus, which forms a bridge to the recipient cell (F-), and the recipient successfully receives the plasmid, the recipient cell will become F+, and if the plasmid integrates into either cell’s chromosome, the cell will become Hfr (high frequency of recombination).
Transduction: a bacteriophage is used to insert foreign DNA
Transformation: the takeup of DNA from the environment
Identify the three possible fates of incoming DNA fragments during HGT
It’s incorporated as an extrachromosomal factor, it becomes recombinant DNA (becomes a part of the genome), or it’s not integrated and the cell breaks it down
