(4) Microbial Genetics Flashcards
what is a genome
genome is an organism’s complete set of genes
what is a gene
gene is a sequence of nucleotides in DNA that encodes for a specific gene product
what is a chromosome
chromosome is a DNA molecule that’s tightly packaged into thread-like structures
what is a plasmid
plasmid is an extrachromosomal DNA that’s seperated from the main chromosomal DNa and can replicate indepedently.
what is DNA
deoxyribonucleic acid
what is RNA
ribonucleic acid
similarities of DNA and RNA
both are genetic information, both have G,C,A nitrogenous bases, both found in nucleus
difference of DNA and RNA
DNA: double-stranded, have thymine, deoxyribonucleic acid, contains all genetic information
RNA: single-stranded, have uracil, ribonucleic acid, gene encodes for protein synthesis
what is monomer of DNA/RNA called
nucleotide
what does nucleotide contains
a phosphate, a 5-carbon ring sugar group and nitrogen base
what are the characteristics of DNA
double-helix, complementary, antiparallel, semiconservative
which are purine and pyrimidine bases
purine: A & G
pyrimidine: T & C
antiparallel characteristic of DNA meaning
1st strand: 5’ to 3’ strands
2nd strand: 3’ to 5’ strands
what are the 3 types of RNA
mRNA (messenger RNA), rRNA (ribosomal RNA), tRNA (transfer RNA)
what is the function of mRNA
contains genetic material that will be translated into amino acid
what is the function of tRNA
to transfer amino acids to the ribosomes for protein synthesis
what are the two DNA in bacterial cell
chromosomal DNA and plasmid
difference in prokaryotic and eukaryotic chromosome
prokaryotic: chromosome in cytoplasm
eukaryotic: chromosome in nucleus
what is the measure of genome
kilobases (Kb) 1000 base pairs or megabases
what are the regions in plasmid
origin of replication, cloning site, antibiotic resistance site
what is structural gene
a sequence of gene that code for mRNA or protein product
what is regulatory gene
a gene involved in controlling gene expression
define mutation
a change in a DNA sequence
what is spontaneous mutation
a mistkaes during DNA replication and no mutagens involved. it’s a random event. (similar to making a typo)
cause of mutation
random event, mutagen, transposon, deletion or insertion of dna, genetic transfer
what are the outcome of mutations
no change, altered function or loss of function
define point mutation
change of a single nucleotide to one of the other three possible nucleotides
what is a transition mutation
a point mutation where a purine changes to another puring (A<->G) or pyrimidine to another pyrimidine (C<->T)
what is a transversion mutation
a point mutation where purine (A or G) replaces pyrimidine (C or G) or vice versa
define missense mutation
the change of a single base pair causes the production of a different amino acid in resulting protein
example of missense mutation
hemoglobin mutation or sickle cell anemia
define non-sense mutation
change in DNA that causes protein to terminate/end its translation earlier. this produce a short or nonfunctional protein
what is gene insertion
changes in DNA sequence by adding one or more nucleotide to the gene
what is gene deletion
the removal of one or more nucleotide from the gene that changes the DNA sequence
3 ways of genetic transfer in bacteria
transformation, conjugation, transduction
explain what is transformation genetic transfer
the process of gene trasnfer where DNA is transferred as a naked DNA.
explain what is conjugation genetic transfer
gene transfer where recipient bacterium recevies DNA from donor bacteria through cell-to-cell contact (a pilus/pili)
explain transduction
gene transfer where a virus is used to transfer genetic material from one bacterium to another
what is griffith’s experiment (1928)
developing a vaccine for pneumonia using two strains of Streptococcus pneumoniae
