Final Flashcards
What is an endocycle?
DNA replication without mitosis or cytokinesis
What are polyploid cells?
When two winged flies (like Drosophila) continue to replicate their chromosomes within the nucleus.
Why are polyploid cells advantageous?
Individual cells are able to grow to a very large size because they carry many copies of each gene �
This allows quick growth because no time is wasted going through mitosis or in preparation for mitosis.
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What is mycelium?
Filamentous growth
Perithecium
A bag full of asci
Ascus
product of one zygote that has undergone meiosis and mitosis, eight ascospores
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dihybrid cross of unlinked traits produces what in the F2 generation?
They produce all phenotypic traits in the F2 generation.
9:3:3:1 ratio of…
parental dominant : dom&rec : rec&dom : parental recessive�
Dihybrid cross of 100% linked traits produces?
3:1 ratio of only parental phenotypes
What are results of a dihybrid cross with PARTIALLY linked traits?
the 9:3:3:1 ratio would be skewed such that there would be a greater representation of the parental phenotypes and fewer of the recombinant phenotypes�
How to calculate map units..
Crossover rate = M2/2 = map units
1 % crossover rate (e.g.1 crossover event in 100) = 1 map unit
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Why only half of the %M2?
Only half of the spores in an M2 pattern are the result of crossing over (two of the chromosomes are unaltered)
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What are SINE’s
highly repetitive sequences that don’t code for any genes
they are TRANSPOSABLE ELEMENTS that are capable of moving to different locations within a given genome.
What is needed for PCR?
Template DNA
Primers
Deoxynucleotides (dATP, dCTP, dGTP, dTTP)
Magnesium ions (enzyme cofactor)
Buffer
Heat-stable DNA polymerase (Taq polymerase)�
What is the purpose of InstaGene Chelator?
it binds intracellular Magnesium
What are the steps of PCR?
Heat (94°C) to denature DNA strands (strands separate)
Cool (60°C) to anneal primers to template
Warm (72°C) to activate Taq polymerase, which extends primers and replicates DNA
Repeat multiple cycles
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p+q=1 is the equation for?
the frequency of the two alleles, p and q, in decimal form
The Hardy-Weinberg equation is for?
The genotype frequencies
What is the hardy weinberg equation and what does each letter stand for?
p2 + 2pq + q2 = 1
p^2 = the frequencies of the homozygous dominant genotypes�
2pq = the frequencies of the heterozygous genotypes
q^2 = the frequencies of the homozygous
recessive genotypes�
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What are the Hardy Weinberg frequencies?
p + q = 1, represents the f (frequency) of ALLELES in a population
p2 + 2pq + q2 = 1, represents the f of GENOTYPES in a population
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Describe the 5 criteria for Hardy Weinberg equilibrium populations?
1) Infinitely large population
2) No natural selection
3) No genetic drift/gene flow
4) No mutations
5) Random mating
What pathway produces bright red pigment?
Drosopterin pathway
What pathway produces brown pigments?
Ommochrome Pathway
which two genes are on the same chromosome (2)?
Cinnabar and brown
The functional Brown gene is involved in the production of what color pigment?
Red pigments
Brown mutants have brown eyes because the red pigment pathway is disrupted �
The functional Scarlet gene is involved in the production of what color pigment?
Brown pigments;
Scarlet mutants have bright red eyes because the brown pigment pathway is disrupted
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What is epistasis and what is an example?
The action of one gene on another genes function.
Apterous overrides any other wing mutation.. LIke if Curly wing and apterous were two genes then fly would be wingless.
What is Quantitative continuous data?
Data that has measurable values which may fall anywhere within a finite or infinite range
e.g. Height, weight, velocities
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What is Categorical nominal data?
Data that can be assigned a single label, but the information can’t be ordered or “measured”
Gender is an example. Individuals can be assigned to a category (male or female), but there is no order to that information, nor is their a measure of “how much” of a male or female an individual is
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What are positive controls?
- Helps detect “false negatives”
An experimental set up that should produce a signal
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What are negative controls?
- Helps detect “false positives”
An experimental set up that should NOT produce a signal
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What is a chi square analysis?
a test for significant difference between 2 data sets…observed vs expected�
What is the equation for chi square?
x^2 = sum of (O-E)^2/E
When p>0.05 then chi square value is_____ and we _______ the null hypothesis.
small; fail to reject
When p<0.05 then chi square value is_____ and we _______ the null hypothesis. (i.e. the null has a less than 5% chance of being correct)
large; reject
What does a large chi square indicate?
large difference between observed and expected= rejecting null
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What does a small chi square indicate?
small difference between observed and expected= failing to reject null
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What is the critical value?
The value that is the borderline between accepting or rejecting the null hypothesis.
What is the p-value?
The probability that your null hypothesis is actually correct.
What does a p-value of 0.05 indicate?
Chance of the observed effect is low (due to random chance) and it’s good evidence that a significant change took place.
What is the null hypothesis?
Change is due to random error (lab error)
What is the NEGATIVE CONTROLS needed for PCR?
-Template (DNA you want to amplify for study)
-Sequence specific primers flanking the target sequence
-Nucleotides (dATP, dCTP, dGTP, dTTP)
�-Magnesium ions (enzyme cofactor)
�-Buffer, containing salt
�-Taq polymerase
What is CODIS?
Combined DNA Index System
What is a multiplex PCR?
PCR with multiple sets of primers in one reaction; amplifies multiple sequences simultaneously.
What are the 3 loci we used in DNA typing?
CSF1PO, TPOX, and THO1
What is a microvariant?
Noted as the number of whole repeats followed by the number of nucleotides of the partial repeat (e.g. 9.3)�
What is the product rule?
the chance of having a certain DNA type at multiple loci is the product of the probabilities for each locus.
Polyacrymalide (PAGE) vs. Agarose
Polyacrylamide gels are denser, holes in matrix of gel are smaller - better for sorting out smaller molecules (DNA or proteins)
Agarose gels are more open – good enough for sorting out larger molecules (DNA)
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Why did THO1 locus have two bands for each allele?
Because when denatured the 2 strands of DNA are separated resulting in doublets
Genetically modified crops…
What are the GMO-specific sequences?
Look at GMO primers;
A 203 bp fragment of the caulifower MV 35S PROMOTER
A 225 bp fragment of the NOS TERMINATOR used in most GMO plants
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What are the plant-specific sequences?
Look at plant primers;
Amplify a 455 bp region of the photosystem II (PSII) chloroplast gene found in most plants
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What are the 5 steps to genetically modify a crop?
1) Identify the protein of interest
2) Isolate the gene that codes for that protein
3) Engineer a gene so plant cells transcribe and translate the protein
4) Introduce the gene into a plant cell
5) Grow the crop with recombinant DNA
What is artificial selection?
The breeder chooses desirable traits in plant to be expressed in next generation.
What is polyploidy/aneuploidy?
An abnormal number of chromosomes; either one extra chromosome or one missing.
Occurs during cytokinesis
What is an example of aneuploidy?
Seedless fruits like bananas and watermelon.
Odd numbered polyploidy results in sterile plants.
What is bacterial transformation?
Uptake and expression of foreign DNA usually by means of a plasmid in bacteria.
What is the meaning of competent?
When bacteria are able to be transformed
Describe the plasmid (pGLO) we used in the bacterial transformation?
It contained an ampicillin resistance gene (always expressed)
It contained an Ara promoter which was turned on in the presence of arabinose. Will ultimately control GFP expression
Describe the starting bacteria we use for transformation?
E. coli bacterial cells whose growth is inhibited by antibiotics and made competent.
Can’t grow or glow…..