ch 9 micro
an operon encoding amino acid biosynthetic enzymes an operon encoding vitamin biosynthetic enzymes
Which two of the following operons in E. coli would be repressible?
recombination
---- refers to the transfer of genes from donor to recipient microorganisms, where the recipient strain shows a change in genetic makeup at the end.
Define operon. Identify spontaneous and induced mutations. Describe the regulator of the lac operon.
Your most challenging concepts
helicase, polymerase
_____ unwinds dna and _____ adds th nucleotides
Horizontal
_____gene transfer occurs when organisms acquire genes which did not come directly from parent organisms
Frameshift
___mutations are generally most harmful to cells because they cause the greatest change in the amino acid sequence of a protein.
MRNA
a copy of the DNA template corresponding to a protein-encoding ge
gene
a sequence of DNA nucleotides that codes for one functional protein or RNA.
ligase DNA polymerase helicase
dna repilcaiton enzymes
dna polymerase
he enzyme that synthesizes DNA strands in the 5' to 3' direction.
uaa, uag, uga
how many stop codons r there>?? name them
transduction
involves the transfer of DNA via bacteriophages.
Transformation
involves the uptake of free DNA by competent bacterial cells.
Transcription
is the process of decoding DNA into messenger RNA.
Translation
is the process of decoding the messenger RNA into a polypeptide
Transposons
jumping genes
nonsense
mutation results in early termination of the protein.
Guanine
Cytosine
transcription
RNA polymerase binds the DNA promoter to initiate
leading
Which strand is replicated continuously without segments during DNA replication?
lagging
Which strand is replicated discontinuously in segments during DNA replication?
ultraviolet light 2-amino purine
Which two of the following are responsible for induced mutations?
Transduction
Which recombination method involves transfer of DNA via bacteriophages?
1:1
A DNA triplet encodes ______ mRNA codon(s) and ______ amino acid(s).
point mutaiton
A mutation that affects only a single base pair in DNA
missense mutation
A mutation that leads to the insertion of a different amino acid in the encoded protein is termed a
missense mutation
A mutation that leads to the insertion of a different amino acid in the encoded protein is termed a___________
mutagen
An agent that induces changes in DNA
recombinant
An organism that contains and expresses genes that originated in another organism is called a(n)
strain
An organism that has a mutation is called a mutant__
inducer
Because lactose is ultimately responsible for stimulating protein synthesis from the lac operon, it is called the
bind to the operator sequence
Binding of arginine to the arginine repressor protein causes the repressor to
leave the operator sequence
Binding of lactose to the lactose repressor protein causes the repressor to
damaged DNA
DNA repair enzymes have as their substrate
RNA is single-stranded In RNA, uracil replaces thymine
How does RNA differ from DNA in bacteria and eukaryotes?
operon
In bacteria, a regulatory gene, a control region, and structural genes collectively are referred to as a(n)
exons
In eukaryotes, coding regions of DNA that will be translated into protein are called
okazaki fragments
In replication of DNA, the lagging strand is replicated in a discontinuous manner forming
helicase DNA polymerase ligase
Select the enzymes that function in DNA replication.
Template DNA
Stand of original DNA that transcription occurs on.
lagging
The ---strand contains Okazaki fragments.
actively greowing
The arginine operon is "on" when the cell is
induces a conformational change in the protein
The binding of arginine to the arginine repressor protein causes the repressor to bind to the operator region. This happens because arginine
induces a conformational change in the protein
The binding of lactose to the lactose repressor protein causes the repressor to leave the operator region. This happens because lactose
low amino acids
The biosynthesis of the amino acid histidine requires several enzymes whose genes are organized in the his operon. The his operon would be expected to be active when the cell is growing in a medium containing
histidine
The corepressor of the histidine biosynthetic operon is
catabolize lactose
The genes of the lac operon in E.coli encode enzymes that __
corepressor
The histidine operon is normally expressed to synthesize histidine for the cell. The operon is turned off only when histidine is present in excess, and the excess histidine serves as a____ to turn off the operon
operator
The lactose repressor protein binds to the ____ of the lac operon
repressor protein
The regulator of the lac operon is a gene that encodes
tru
The start codon AUG is associated with the tRNA anticodon UAC and the amino acid methionine.
false: theyre made of DNA and histone proteins.
True or false: Eukaryotic chromosomes are composed of DNA and RNA.
False
True or false: Plasmids are insertion sequences that can lead to changes in genotype within a cell or between cells.
That DNA released from a dead cell can be transferred to live cel
What did Griffith's experiment using Streptococcus pneumoniae demonstrate?
bring aminos to ribosome
What is the function of tRNA?
Nonsense mutation
What is the result of a point mutation that changes a template gene sequence from 3'-TACGCCATATAT-5' to 3'-TACGCCATCTAT-5'?
repressed until the glucose is consumed
When E. coli is grown in a medium containing both glucose and lactose, the lac operon will be
on; actively synthesized
When a cell is actively growing, the arg operon is _____, and arginine is _____.
ligase
Which enzyme completes the final sealing of nicks in a newly synthesized DNA strand?
transformation
Which gene transfer method involves the uptake of free DNA by competent bacterial cells?
DNA polymerase
Which is the main enzyme in elongation of a DNA strand during replication?
mRNA binds to the ribosome
Which is the main event of translation initiation?
lactose
Which molecule is the inducer of the lac operon?
Conjugation Transformation Transduction
Which of the following are methods of gene transfer in bacteria?
errors in DNA replication
Which of the following is responsible for spontaneous mutations?
he pyr operon, encoding pyrimidine biosynthetic enzymes the rib operon, encoding riboflavin biosynthetic enzymes the thr operon, encoding threonine biosynthetic enzymes
Which of the following operons in E. coli would be repressible?
operon
Which operational unit in bacteria consists of a regulatory gene, a control region, and structural genes?
reduncancy
of the genetic code results in several codons encoding the same amino acid. Listen to the complete question
a g
purines
t c u
pyrimadines
rna polymerase
s the enzyme that transcribes DNA into RNA.
promoter
specific region of a gene where RNA polymerase can bind and begin transcription
semiconservative Replication
the DNA is duplicated prior to binary fission.
lactose repressor
the ____ binds to the operator of the lac operon.
promoter
the ____ of the lac operon is a region of DNA that is recognized by RNA polymerase
regulator
the____ of the lac operon is a gene that encodes a repressor protein.
amino acids
trna carries _____ ___ to the ribosome to build peptide chains during protein synthesis