Microbial Genetics and Mutation Flashcards
What is a heritable change in the base sequence of a genome that is passed from the mother cell to progeny cells?
Mutation
What are the 2 types of transduction?
Generalized and specialized
What is the total complement of genetic elements?
Genome
What is the difference of conservative missense mutation and non-conservative missense mutation?
Both of them synthesize protein however in conservative missense, the physiochemical properties are the same with the physiochemical properties of the original protein while it is completely different in non-conservative
What are the 3 possible fates of DNA when it enters the cell by horizontal gene transfer?
Degrade by restriction enzymes, Replicate by itself, Recombine with the host chromosomes
Enumerate the 3 types of horizontal gene transfer?
Transformation, Transduction, Conjugation
What is the variety of chemical, physical, and biological agents that induces mutation?
Mutagen
Enumerate the 3 stages of genetic information flow
Replication, Transcription, and Translation
Where do the process of replication and transcription in eukaryote cell take place?
Nucleus
What are the effects of point mutation?
Silent, Missense, Nonsense, Transition, Transversion
True or False: If damaged DNA can be corrected before the cell divides, no mutation will occur
True
What component of DNA and RNA that is found on the 5th carbon of the pentose sugar?
Molecule of phosphate
What do you call the type of horizontal gene transfer that requires cell to cell contact through sex pili?
Conjugation
Where do the process of replication, transcription, and translation in prokaryotic cells take place?
Cytoplasm
Enumerate the molecular basis of mutation.
Induced, Spontaneous, Point, Frameshift
What is the estimated minimum number of genes possible for a viable cells?
around 250-300 genes
How do prokaryote replicate?
At a certain side of the circular DNA, it will cleave by an enzyme. From there, the DNA polymerase will attach itself to the DNA and starts the process of complementation or the filling up of sequences that will become complementary with the DNA template. From there, there will be a new sequence complemented with the parent sequence producing 2 circular DNAs.
What is the code, algorithm or blueprint that can be encoded or translated for a certain function like growth and development?
Genetic information
This is a molecular basis of mutation that occurs without external intervention.
Spontaneous mutation
What do you call the effect of point mutation that happens when a purine base is substituted for another purine or when a pyrimidine base for another pyrimidine base?
Transition
What do you call the physical exchange of DNA between genetic elements?
Recombination
What is the 3rd step or molecular event in homologous recombination?
Base pairing in turn displaces the other strand of the recipient DNA molecule.
This is an example of nucleotide base analog that is the derivative of uracil.
5-Bromouracil
What is the pair of Adenine in DNA in the specific base pairing?
Thymine
What is the 1st step in SOS repair system?
Activated by the stalled replication and certain types of major DNA damage
Under radiation mutagen, what damages sequences resulting to disabling multiplication process of microbes?
Ultraviolet radiation
This is the 2nd type of horizontal gene transfer wherein it uses a bacterial virus to transfer DNA from one cell to another. example: antibiotic resistance
Transduction
Why does plasmid is being transferred to recipient cells?
Because it carries advantageous genes.
Why does the genome of parasitic bacteria smaller compared to the free living?
Since they only depend on the cells of the free living, they do not need it anymore. It is also easier to replicate since their genomes are small. (base lang yung sagot sa pagkakaintindi ko huhu di ako sure)
True or False: Mutation always leads to bad changes in the properties of an organism.
False
It is a molecular basis of mutation caused by base-pair substitution in the DNA or by the loss or gain of a single base pair.
Point mutation
What is the difference of eukaryotes and prokaryotes when it comes to translation?
In eukaryote, there is an additional step in translation wherein the produced mRNA strand will have a cock and tail on both of its end. It prevents the strand to be killed once it released from the nucleus. Once it is released, ribosomes will attach to it, initiating the process of translation. All of this do not happen in prokaryote.
Under chemical mutagens, what induces chemical modification in one base or another, resulting in faulty base pairing or related changes?
Alkylating agents
What do you call a type of transduction wherein the DNA from a specific region of the host chromosome is integrated directly into the virus genome?
Specialized transduction
What do you call a double-stranded that is being held together by hydrogen bonds between the bases in the two strands?
DNA
What do you call the effect of point mutation wherein there is an alteration in the sequence but it does not affect the phenotype of the cell or does not have any physical change on the cell?
Silent mutation
What is the 3rd step in the SOS repair system?
Because of rapid activation of the repair system, it allows the DNA repair to occur without a template resulting in many errors and hence many mutations
What do you call a gene transfer wherein it transfer genes by creating or producing an exact copy of themselves?
Horizontal gene transfer
What are the other 2 components of DNA and RNA?
Pentose sugar and Nitrogen bases
True or False: Exposure to natural radiation that alters the structure of bases in DNA is a good effect of induced mutation
True
It is a stage of genetic information flow wherein protein is synthesized.
Translation
What attaches to the DNA to initiate the process of transcription?
RNA polymerase
What do you call a strain of an organism that is isolated from the nature?
Wild type
What effect of point mutation is when purine base is substituted for a pyrimidine base or vice versa?
Transversion
What is the 4th step or molecular event in homologous recombination?
The foreign DNA and the host DNA successfully links and complemented with the other resulting to DNA sequences that combines genetic information of both DNAs.
What is the simplest form of genetic transfer process wherein free DNA is incorporated into a recipient cell and brings about genetic change?
Transformation
What do you call the type of transduction wherein DNA is derived from virtually any portion of the host virion in place of the virus genome?
Generalized transduction
What is the 5th step of transformation?
One parental and one recombinant DNA molecule are generated
True or False: Exposure to low dosage of antibiotic is a bad effect of induced mutation.
True
What is the effect of point mutation that changes a sense of codon to a nonsense codon?
Nonsense mutation
What is the sections or portions in the nucleic acid sequence in the genome that has the ability to be translated?
Open reading frame (ORF)
What is the difference of eukaryotic cells and prokaryotic cells when undergoing the process of transcription?
In eukaryotic cells, only one RNA polymerase will attach to the complementary strand of DNA. From there it will line up the free living nucleic acid-base pairs to form an mRNA. However, in prokaryotic cells, a lot of RNA polymerase will attach to the sequence of the DNA for it to form many mRNA strands.
Simply explain the stages of genetic information flow
In replication, the DNA is replicated. Then in transcription, DNA is converted to RNA. Lastly, RNA is to be translated to amino acid sequence which will be a protein is what happens in translation.
What is the 1st step or molecular event in homologous recombination?
Endonuclease begins the process by nicking or breaking one strand of the donor DNA molecule
What is the difference of generalized transduction and specialized transduction?
Generalized transduction targets DNA from any portion of the host genome while specialized transduction targets DNA from a specific region of the host genome (again, sariling intindi ko lang. di ko sure)
It is a molecular basis of mutation wherein any deletion or insertion of base pairs results in a shift in the reading frame.
Frameshift mutation
What is the functional unit of genetic information?
Gene
True or False: Each megabase pair of DNA in prokaryotic cell encodes about 1000 open reading frame (ORF).
True
What do you call the effect of point mutation that causes change in informational “sense” in the polypeptide?
Missense mutation
What do you call those derived from the wild type that carries a change on nucleotide sequence?
Mutant
What is the 2nd step or molecular event in homologous recombination?
The nicked or broken strand is separated from the other strand and the resulting single-stranded segment binds in single-stranded binding protein and RecA.
Under radiation mutagen, this causes water and other substances to ionized resulting in the formation of free radicals. This literally breaks down or damages DNA resulting to faultiness in the replication of DNA sequence.
Ionizing radiation
This is the 2nd stage of genetic information flow wherein RNA is being synthesized using DNA as a template. Once RNA polymerase has bound to initiation site, DNA double helix is opened up exposing the template strand and allowing it to be copied into RNA complement.
Transcription
What are the 2 nitrogen bases?
Purines and Pyrimidines
What is the 1st step of transformation?
Transforming DNA is bound at the cell surface by a DNA-binding protein
What is the 3rd step of transformation?
DNA is bound by a competence-specific protein, the SSB protein, and integrated into the genome of the recipient by recombination
Under chemical mutagen, this agent is inserted between two DNA base pairs and push them apart.
Intercalating agent
What is the 4th step on the SOS repair system?
Once the original DNA damage has been repaired, the SOS regulation is repressed and further mutagenesis ceases
What antiparallel fashion does one strand runs 5’ to 3’?
Top to bottom
What can be express or translate proteins to form a structure needed by the body for growth?
Gene
What is the 2nd step in transformation?
Double-stranded fragment is wither taken up entirely or a nuclease degrades one strand and the remaining strand is taken up
Under radiation mutagen, what radiation is for disinfection and sterilization?
Ultraviolet radiation
What do you call the gene and chromosome and other large molecules that support and protect genetic information, or help carry out the functions of the genetic information?
Genetic elements
True or False: If the genome is smaller, there are many ORF
False: If the genome is larger, there are many ORF
What is the 2nd step in SOS repair system?
Initiates a number of DNA repair processes
What is the last step of transformation?
During cell division, the recombinant molecule is present in the transformed cell
What do you call the type of horizontal gene transfer wherein the DNA of the host is being transported into the recipient cell thru a phage
Transduction
Under chemical mutagens, what do you call molecules that resemble purine and pyrimidine bases of DNA in structure yet display faulty pairing properties?
Nucleotide base analogs
What antiparallel fashion do a complementary strand runs 5’ to 3’?
Bottom to top
What do you call a bacteria that is exposed to a certain mutagen?
Mutant
