Ch. 9 connect practice questions
DNA polymerase __ is involved in repair
1
Genes are made up of ___, a macromolecule made of nucleotides
DNA
T/F: mutations are always harmful to cells
False, some mutations help cells survive
What occurs during posttranslational modification?
Formyl methionine (f-met) is removed; quaternary structures form, a tertiary protein conformation forms, cofactors are added to proteins destined to become enzymes
Which type of mutation is generally most harmful to cells?
Frameshift mutation
A ___ mutation involves a shift of the triplet sequence form the point of mutation downstream
Frameshift; the reading of the mRNA has been changed.
The entire genetic makeup of an organism is it ___)
Genotype
A ___ mutation results in early termination of the protein
Nonsense
Chromosomes are located in the ___ of protozoal and fungal cells
Nucleus
The expression of certain genetic traits are known as its
Phenotype
Which process repairs DNA that has been damaged by UV radiation using visible light?
Photoactivation
Donor and recipient bacterial cells are connected by the sex ___ during conjugation
Pilus
What is a small segment of DNA found in the cytoplasm of prokaryotes that is capable of independent replication and usually contains nonessential genes?
Plasmid
DNA ____ is the enzyme responsible for building strands of DNA
Polymerase
___ mutations in DNA are caused by random mistakes in replication and not known to be influenced by any mutagenic agent
Spontaneous
Which recombination method involves transfer of DNA via bacteriophages?
Transduction
During the process of ___ a competent bacterial cell may accept soluble DNA from the surrounding environment
Transformation
Griffith's experiment using streptococcus pneumoniae demonstrated the process of
Transformation
___ involves the uptake of free DNA by competent bacterial cells
Transformation
___ are able to shift from one part of the genome to another
Transposons
T/F: R-factors or "resistance factors" can be shared between bacteria through conjugation to help them survive the effect of antibiotics.
True
Transduction occurs through a
bacteriophage
A ___ mutation results in a different amino acid being incorporated into a protein , with varying results
missense
A ___ is the basic unit of DNA structure
nucleotide
A DNA triplet encodes ___ mRNA codon(s) and ___ amino acid(s)
1; 1
A codon contains how many nucleotides?
3
DNA polymerase ___ constructs the new strand
3
All new DNA strands are synthesized: 3 to 5 or 5 to 3?
5' TO 3'
In DNA, a purine always combines with ___
A pyrimidine
What is the main effect of ultraviolet radiation on DNA?
Abnormal bonding between adjacent pyrimidines
Which test is used to determine the carginogenic potential of a chemical
Ames test
Plasmids are found in which type(s) of organisms?
Bacteria Fungi
DNA polymerases are responsible for:
Building the DNA chain Proofreading/repair
The genome of a prokaryotic or eukaryotic cell includes DNA found in which sites:
Chloroplasts Plasmids Chromosomes Mitochondria
R factors are specifically associate with which mechanism of recombination?
Conjugation
___ in bacteria refers to horizontal gene exchange via pili
Conjugation
The blueprint information for the production of proteins is permanently encoded in sections of
DNA
DNA polymerase __ is involved in removing the RNA primer, closing gaps, and repairing mismatched bases
DNA polymerase I
The enzyme involved in replicating a new strand is
DNA polymerase III
Proteins contribute to the phenotype of an organism by functions as:
Enzymes & structural molecules
Proteins that remove incorrect bases and replace them with correct ones are termed ___ enzymes
Excision repair
Which process repairs DNA that has been damaged by UV radiation in absence of light?
Excision repair
Adenine and ___ are purines found in DNA
Guanine
RNA polymerase is different from DNA polymerase in that a ____ enzyme is not required
Helicase
What type of DNA mutation occurs as a consequence of exposure to chemical or physical mutagens?
Induced
A(n) ____ operon, can be turned on when the appropriate substrate is present.
Inducible
Stages of transcription:
Initiation Elongation Termination
The three events of translation are ____, ____, and ____ followed by ___ and ____
Initiation, elongation, termination, protein folding, and processing.
A chemical or physical agent that induces a change in DNA is referred to as a
Mutagen
Which mutation changes an amino acid producing codon into a stop codon?
Nonsense
In bacterial conjugation, a donor cell with a F (fertility) ___ located in the cytoplasm is considered F+
Plasmid
Mutations that involve the addition, deletion or substitution of a single base are referred to as
Point mutations
The large enzyme complex involved in synthesizing RNA from a DNA template is which enzyme?
RNA polymerase
The central dogma of genetics states that DNA encodes ___ which encodes ___
RNA; protein
Which term refers to the transfer of genes between donor and recipient microorganisms?
Recombination
What must occur prior to cell division to ensure that each new cell has a complete set of DNA chromosome(s)?
Replication
RNA polymerase
Synthesizes an RNA molecule from DNA template Unwinds the DNA so that transcription can take place
How do an Hfr cell and an F+ cell differ?
The plasmid is integrated into the chromosome of an Hfr cell but not in an F+ cell
The process of decoding DNA into mRNA
Transcription
What are the 2 steps of protein synthesis?
Transcription Translation
A ___ serves as the vector for transduction in bacteria
bacteriophage
A nucleotide is oriented 5' or 3' depending on the location of the ___ on the strand of DNA
deoxyribose sugar
During translation, ___ is converted into a protein
mRNA
Which type of RNA is the transcribed version of a structural gene in DNA?
mRNA
Gram ___ cells conjugate and transfer genetic material through pores in their cell walls instead of __
positive; pili
During translation, mRNA is converted into a ___
protein
During ____ , mRNA is converted into a protein
translation
