Ch.8 Microbial genetics

Question 1

where do plasmids exist?

Answer 1

in cells separate from chromosomes

Question 2

mutations can be caused by ?

Answer 2

base substitutions or frame shift mutations

Question 3

typical chain of events described by central dogma

Answer 3

dna—>mrna–>protein–>function

Question 4

how mutations alter a genome?

Answer 4

mutated dna–>altered mrna–>altered protein–>altered function

Question 5

many bacterial diseases are caused by the presence of ? which are coded by ?

Answer 5

toxic proteins

genes

Question 6

when populations are large enough in biofilm formation they are produced by ?

Answer 6

altered gene expressions

Question 7

mutations in the genome cause bacteria to be what?

Answer 7

antibiotic resistant

Question 8

what is a benefit of altering a bacteria’s genome?

Answer 8

scientists can add genes that will produce human proteins used for treating diseases
an example is insulin

Question 9

dna expression leads to ?

Answer 9

cell function via the production of proteins

Question 10

genes in operons?
mutations alter?
dna mutations can change?

Answer 10

are turned off and on together
dna sequence
bacterial function

Question 11

the study of genes, how they carry information, how information is expressed, and how genes are replicated

Answer 11

Genetics

Question 12

: structures containing DNA that physically carry hereditary information; the chromosomes contain genes

Answer 12

Chromosomes

Question 13

segments of DNA that encode functional products, usually proteins

Answer 13

Genes

Question 14

all the genetic information in a cell

Answer 14

Genome

Question 15

is a set of rules that determines how a nucleotide sequence is converted to an amino acid sequence of a protein

Answer 15

genetic code

Question 16

the genetic makeup of an organism

Answer 16

genotype

Question 17

expression of the genes (observable characteristics)

Answer 17

phenotype

Question 18

t/f bacteria usually have single circular chromosome made of DNA and associated proteins

Answer 18

TRUE

Question 19

repeating sequences of noncoding DNA

Answer 19

Short tandem repeats (STRs)

Question 20

flow of genetic information from one generation to the next

Answer 20

vertical gene transfer

Question 21

what is involved in the flow of genetic informations?

Answer 21

expression, recombination,replication

Question 22

Genetic information is used
within a cell to produce the
proteins needed for the cell
to function.

Answer 22

expression

Question 23

Genetic information can be
transferred horizontally between
cells of the same generation.

Answer 23

recombination

Question 24

Genetic information can be
transferred vertically to the
next generation of cells.

Answer 24

replication

Question 25

Why is the base pairing in DNA important?

Answer 25

the sequence of bases allows it to carry coded information for making proteins. It is very long so it stores lots of information. Complementary base pairing allows the molecule to replicate itself accurately.

Question 26

Order of the nitrogen-containing bases does what?

Answer 26

forms the genetic instructions of the organism

Question 27

what does the backbone of dna consist of ?

Answer 27

deoxyribose-phosphate

Question 28

t/f the strands of dna are parallel?

Answer 28

False they are anti parallel | one strand is upside down relative to the back bone of the other

Question 29

what do Topoisomerase and gyrase do for dna? | what does Helicase do?

Answer 29

they relax the strands | separates the strands

Question 30

what does DNA polymerase do and in what direction does it do it?

Answer 30

adds nucleotides to the growing DNA strand as well as removes RNA primers in the 5>3 direction

Question 31

what is the differences between the leading strand and the lagging strand?

Answer 31

the leading strand is synthesized continuously while the lagging strand isnt creating Okazaki fragments

Question 32

replication of dna strands require energy where do they get their energy from and how?

Answer 32

supplied by nucleotides | Hydrolysis of two phosphate groups on ATP provides energy

Question 33

T/F Most bacterial DNA is Bidirectional (functioning in two directions)

Answer 33

TRUE

Question 34

Each offspring receives ?

Answer 34

one copy of the DNA molecule

Question 35

why is replication highly accurate

Answer 35

bc of the proofreading capability of DNA polymerase

Question 36

the site where dna helicase unzips the dna (meaning it breaks the hydrogen bonds holding the two strands together )is called the ?

Answer 36

replication fork

Question 37

DNA Polymerase can only add bases to the ___ end of a nucleic acid it cannot start replication from scratch

Answer 37

3

Question 38

the enzyme primase does what ?

Answer 38

synthesizes a short piece of RNA called an RNA primer from a dna template

Question 39

what does the RNA primer do?

Answer 39

the RNA primer provides a 3 end on which dna polymerase can act on

Question 40

what does RNase do?

Answer 40

removes the rna primers leaving a gap in the dna whcih can then be filled by dna polymerase

Question 41

function of DNA ligase?

Answer 41

seals the gaps between the dna fragments (okazaki)

Question 42

what are the 3 characteristics of RNA

Answer 42

Single-stranded nucleotide 5-carbon ribose sugar (hence ribo) instead of deoxyribo Contains uracil (U) instead of thymine (T)

Question 43

used to form ribosomes, integral part of ribosomes, and is essential for protein synthesis in all living organisms

Answer 43

rRNA

Question 44

transports amino acids to the ribosome to make proteins

Answer 44

tRNA

Question 45

carries coded information for making specific proteins from DNA to ribosomes

Answer 45

mRNA

Question 46

When does transcription in prokaryotes start?

Answer 46

when RNA polymerase binds to the promoter sequence on DNA | Transcription proceeds in the 5‘ 3' direction; only one of the two DNA strands is transcribed

Question 47

when does transcription stop?

Answer 47

when it reaches the terminator sequence on DNA

Question 48

what is the purpose of transcription?

Answer 48

the information stored in dna is copied into rna molecules which is used to synthesize specific proteins

Question 49

what are the three stages of transcription?

Answer 49

initiation, elongation, termination

Question 50

what happens in the initiation stage?

Answer 50

the rna polymerase binds to DNA recognizes the promoter at the 3 end then moves along the promoter and breaks the hydrogen bonds that hold the dna together at the promoter site and transcription begins

Question 51

T/F RNA polymerase binds to all promoters with equal affinity?

Answer 51

false the different promoter affinities is one way to control gene expression

Question 52

what happens during the elongation stage?

Answer 52

rna polymerase moves along the dna opening up a bubble in the dna and as it moves along it adds basses to the 3 end of the growing rna transcript

Question 53

what happens during the termination stage

Answer 53

when rna polymerase reaches the termination stage transcription stops by either self self termination or enzyme dependent termination