Module 6 Genetics Flashcards
Which enzyme is only found in prokaryotic organisms?
DNA gyrase
what is a purine?
a double ring structure with a six-membered ring fused to a five-membered ring
DNA has a ___________ structure.
double helix
The DNA fragments that are synthesized in short stretches on the lagging strand are known as the Okazaki fragments.
true
The replication of DNA occurs during the synthesis phase / S phase of the cell cycle, before the cell enters mitosis or meiosis.
true
In which direction does DNA replication take place?
5’ to 3’
mRNA/messenger RNA is a form of RNA that carries the nucleotide sequence code for a protein sequence that is translated into a polypeptide sequence.
true
RNA contains the nucleotide thymine (T).
false
The central dogma states that genes specify the sequence of mRNAs, which in turn specify the sequence of proteins.
true
A codon is three consecutive nucleotides in mRNA that specify the insertion of an amino acid or the release of a polypeptide chain during translation.
true
mRNA are molecules of RNA that combine to form part of the ribosome.
false
The reading frame is the sequence of triplet codons in mRNA that specify a particular protein; a ribosome shift of one or two nucleotides in either direction completely abolishes synthesis of that protein.
true
The first cloned agricultural animal was Dolly, a sheep who was born in 1996.
true
Genetic engineering may use artificial methods to modify the genetic material of living organisms or cells to produce novel compounds or to perform new functions.
true
Recombinant DNA technology can be used to modify an organism’s DNA to achieve desirable traits.
true
If the foreign DNA that is introduced comes from a different species, the host organism is called __________.
transgenic
_________________ is the most specific genetic engineering technique that may one day be used to cure certain genetic diseases.
gene therapy
In the reproductive cloning of an animal, the genome of the cloned individual comes from ________.
a body cell
__________ is the process of decoding an mRNA message into a polypeptide product.
translation
______ is an RNA molecule that contains a specific three-nucleotide anticodon sequence to pair with the mRNA codon and also binds to a specific amino acid.
tRNA
The RNA components of ribosomes are synthesized in the ________.
nucleolus
Portions of eukaryotic mRNA sequence that are removed during RNA processing are ________.
introns
Transcription occurs in the ______ of eukaryotic cells.
nucleus
A promoter is ________.
a specific sequence of DNA nucleotides
The initial mechanism for repairing nucleotide errors in DNA is ________.
DNA polymerase proofreading
What is the role of Agrobacterium tumefaciens in the production of transgenic plants?
A. tumefaciens is used as a vector to move genes into plant cells.
DNA double helix does not have which of the following?
uracil
What happens when a dideoxynucleotide is added to a developing DNA strand?
the chain is not extended any further
What prevents the further development of a DNA strand in Sanger sequencing?
the addition of dideoxynucleotides
DNA replicates by which of the following models?
semiconservative
Which of the following is not a true statement comparing prokaryotic and eukaryotic DNA replication?
DNA replication always occurs in the nucleus
How many nucleotides are in 12 mRNA codons?
36
The AUC and AUA codons in mRNA both specify isoleucine. What feature of the genetic code explains this?
degeneracy
In eukaryotes, what is the DNA wrapped around?
histones
The ends of the linear chromosomes are maintained by…
telomerase
One of the three mRNA codons that specifies termination of translation is the…
nonsense codon
Manipulating the DNA of plants has helped to create desirable traits such as…
Disease resistance
Pest resistance
Better nutritional value
What is the name of the method developed by Fred Sanger to sequence DNA?
Dideoxy Chain Termination method
Which enzyme initiates the splitting of the double DNA strand during replication?
helicase
The strand of DNA that is not used to transcribe mRNA is the…
nontemplate strand
A researcher has found a single-stranded nucleic acid associated with a ribosome. This molecule is most likely…
RNA
A researcher has broken apart a nucleic acid and has found the following nitrogenous bases: A, T, G, and C. Which molecule is this?
DNA
Using the following template strand of DNA, what would be the sequence of the complementary strand of mRNA that would be synthesized during transcription?
Template strand: 5’ - ATGCTCGATCAG - 3’
3’ - UACGAGCUAGUC - 5’
Using the following strand of DNA and the table below, determine the correct sequence of amino acids of the polypeptide that would be synthesized during translation.
DNA: 5’ - TACGTATGCATG - 3’
Met, His, Thr, Tyr
For the codon CCG, what would be the appropriate anticodon?
GGC
When mutations occur in the DNA, these can impact the final protein strand. Using the table below, determine how the protein produced by the mutant mRNA strain below is different from the wild type (normal) mRNA strand.
Wild Type AUG│AAG│ACU│AUC│AUU│GCU│UUG│AGC│UAC│AUU
Mutant AUG│AAG│ACU│AUC│AUU│GCU│UUG│AGC│UAA│AUU
The protein is shorter than the wild type strain.
When mutations occur in the DNA, these can impact the final protein strand. Using the table below, determine how the protein produced by the mutant mRNA strain below is different from the wild type (normal) mRNA strand.
Wild Type AUG│AAG│ACU│AUC│AUU│GCU│UUG│AGC│UAC│AUU│
Mutant AUG│AAG│ACC│AUC│AUU│GCU│UUG│AGC│UAC│AUU│
There is no difference between the mutated and wild type proteins.
An individual has a mutation in the positive transcription factor that binds to the gene that causes freckles. What impact would this likely have on the phenotype of this individual?
They will have fewer freckles because the gene will be transcribed less frequently.
Assume there is a type of cancer that is caused by a gene that is producing more protein than normal. Which of these would be an effective way to help treat this cancer?
Treat this individual with a negative transcription factor to turn off the cancer-causing gene.
If an individual has a mutation in the gene for RNA polymerase, what is the most likely effect?
a drastic reduction in the amount of transcription
A researcher is examining cells and finds that they have a larger number of ribosomes than normal. Based on this, she concludes…
that these cells have an increased level of translation occurring.
Your physician has diagnosed you with a bacterial infection, and she comments that it is an antibiotic strain of E coli. She knows this because…
the bacteria grew on LB agar with ampicillin.
During bacterial transformation, which type of bacteria are grown on non-selective plates?
antibiotic sensitive bacteria lacking the DNA plasmid
During bacterial transformation, what serves as a nutritional source for bacteria?
LB agar
You are reading an electrophoretic gel and want to find the smallest DNA fragment that was added to the gel. How would you know which was the smallest?
It has traveled the farthest distance in the gel.
You are conducting an experiment where you are trying to determine if the DNA samples you have are from the same individual. Which of the results below indicates that your samples are from the same individual?
All of the bands from both samples travel the same distance.
You have loaded two samples containing DNA of the same dog mixed with tracking dye into the gel. You accidentally set the timer for ten hours instead of ten minutes and allow the gel to run for the entire time. What is the most likely result?
The tracking dye will have moved to the positive end.
DNA and RNA that each contain 20% cytosine will have how much thymine, respectively?
30% in DNA and 0% in RNA
If a mutation causes DNA to have extra adenine, what impact does this have on the overall composition of the DNA?
It will also have extra thymine.
If the mRNA codons are AUG and CGA, what are the corresponding anticodons in tRNA?
UAC, GCU
