Micro Ch 8 Genetics Part 2

Front 1

operon

Back 1

group of genes with a promoter and operator sites, and structural genes which code for proteins.
not in prokaryotes

Front 2

repression

Back 2

(protein) blocks transcription by binding to an operator. Synthesis stops.

Front 3

induction

Back 3

The synthesis of enzymes in the presence of an inducer.

In the absence of an inducer, a repressor binds to the operator of an operon, and turns off transcription. When present, an inducer binds to the repressor and inactivates it.

Front 4

mutation

Back 4

a change in sequence of bases on DNA (or RNA of RNA viruses)

Front 5

mutagen

Back 5

something that causes a mutation. not always needed.

genotype not phenotype

Front 6

point mutation

Back 6

one base substitution.
one thign changes

Front 7

missense mutation

Back 7

amino acid is changed
protein's function wont change much.

Front 8

nonsense mutation

Back 8

mutation creates a stop codon

Front 9

frameshift mutation

Back 9

insertion/deletion of one or few bases.

results in misreading the code.

Front 10

spontaneous mutations

Back 10

occur without a known mutagen

vs induced mutation

Front 11

chemical mutagens

Back 11

nitrous acid and base analogs cause base-pair changes; benzopyrene causes frameshift mutations

sticks itself into the DNA.

Front 12

ionizing radiation

Back 12

x rays and gamma rays cause ion formation which causes break in DNA and errors in DNA replication

cell can't recover after circular dna is broken

Front 13

nonionizing radiation

Back 13

UV light causes thymine dimer formation, and faulty DNA synthesis.
covalent cross links.
excision repair may occur.

Front 14

endonuclease

Back 14

find DNA lesion/distorsion in helix and removie it.

Front 15

DNA repair polymerase/ligase

Back 15

inserts correct pair after endonuclease

Front 16

mutagen rate

Back 16

the probability that a gene will mutate when a cell divides.
expressed as 10 to the negative number

Front 17

spontaneous rate

Back 17

10^-9

Front 18

genetic recombination

Back 18

the exchange of genes between 2 DNA molecules to form a new combo of genes on one molecule of DNA

mostly in prokaryote than eukaryote

Front 19

recombinant cell

Back 19

DNA is transferred from a donor bacterium to recipient bacterium. the recipient becomes this.

basically a new organism.

Front 20

transformation

Back 20

naked DNA Goes from cell to cell

discovered by Griffith in 1928 when he was working with 2 strains of Streptococcus pneumoniae

Front 21

conjugation

Back 21

via cell to cell contact
requires sex pilus
male produces the pilus and finds a female and transfers a plasmid

Front 22

transduction

Back 22

via a virus

Front 23

DNA transfers between bacteria in what ways?

Back 23

transformation
conjugation
transduction

Front 24

plasmids

Back 24

small DS circles of DNA in cytoplasm. 1-5% size of the chromosome
not essential for cell survival
source of genetic variability
not in eukaryotic, prokaryotes can have more than one plasmid

Front 25

type of plasmids

Back 25

dissimilation
virulence
f factors
resistance factors (r factors)

Front 26

dissimilation plasmids

Back 26

code for enzymes that degrade unusual compounds

Front 27

virulence determinants

Back 27

code for virulence determinants, like exotoxins

Front 28

F factors

Back 28

carry genes for sex pili and for transfer of plasmid to another cell

Front 29

resistance factors (R factors)

Back 29

code for proteins to make cell resistant to antibiotics

jas am RTF region and r determinant

Front 30

F+

Back 30

ability to produce the pilus. male with F factor.

female is F-

Front 31

Hfr

Back 31

F factor is part of the chromosome of the pilus. in a male

Front 32

F factor

Back 32

cluster of genes transferred from F+ to F-

Front 33

RTF region

Back 33

resistance transfer factor. includes genes for plasmid replication and transfer

Front 34

r determinant

Back 34

resistance genes, penicillinase.

Front 35

transposons

Back 35

transposable genetic elements. jumping genes.

they move from chromosome --> plasmid, plasmid --> plasmid, plasmid --> chromosome, chromosome -- chromosoem

palindromic

Front 36

transposase

Back 36

cuts out transposable elements. and insert it somewhere else

Front 37

transposition

Back 37

cut a gene out and copy it, paste it somewhere else

an IS or a complex transposon is sipped out and inserted in another location

Front 38

complex transposon

Back 38

carries other gene between 2 insertion sequences. toxin genes/antibiotic resistance

Front 39

significances of recombination

Back 39

increase in genetic diversity/change
allows for adaptation of new environments
*causes partial or full duplication of genetic material (genetic increase)

Front 40

genetic change in microorganisms contributes to

Back 40

antibiotic resistance
host tropism (change in host species)
immune invasion (antigenic change)
increased pathogenicity (ability to cause disease)

Front 41

tuberculosis

Back 41

caused by mycobacterium tuberculosis
gram + rod, aerobe, acid fast

has mycolic acids in cell envelope, cell is resistant to drying and dessication.

grows very slowly

Front 42

tubercle

Back 42

granuloma of macrophages, neutrophils, bacteria, and tissue cells in the lung

Front 43

miliary tuberculosis

Back 43

bacteria cells rupture

Front 44

consumption

Back 44

weight loss because of tuberculosis