Extra MCQ Questions Flashcards
What’s the causative mutation of pleiotropy?
ACAN- aggression gene
-Bull Dog Calf syndrome
What is pleiotropy?
The capacity of a single gene to cause multiple phenotypic effects
Give an example of pleiotropy?
Horn development and intersex phenotype in goats.
If a pleiotropy animal has
1-PP
2-pp
3-Pp
1- Polled
2-Horned
3-Polled
What’s the male progeny of pleiotropy?
3:1
What’s the female progeny of pleiotropy?
1:2:1
What’s the codominance and incomplete dominance ratio?
1:2:1
What is codominance?
when both phenotypes separately manifest heterozygous organisms
Where is co dominance observed?
1- Blood group MN and ABO
2-Roan Coat Colours
What gene determines if a horse will be solid, mottled, or white?
EDNRB-
Endothelin, receptor type B gene
What is epistasis?
A gene that alters the phenotypic expression of another gene at a different genetic locus
eg. Coat colour
How do you calculate the recombination frequency?
recombinants / total number of offspring = answer
What is the extension of DNA at replication fork preformed by?
Enzymes called DNA polymerase
How do genes function to direct biochemical and cellular processes?
A functional RNA molecule
List the functional RNA molecules:
-tRNA
-rRNA
-hnRNA
-snoRNA
-mirRNA
-siRNA
What does miRNA and siRNA regulate?
Expression of individual genes
What’s the 2 main processes linking a gene to a protein?
-Transcription
-Translation
Transcription - definition
The synthesis of messenger RNA (mRNA) from DNA
Translation- definition
The synthesis of a polypeptide using information encoded in a mRNA molecule
In eukaryotic cells, where does translation and transcription occur?
-Translation= cytoplasm
-Transcription= nucleus
Whats the 5’ end of the mRNA capped with?
modified guanine (G)
What is the function of a 5 guanine cap?
It protects the mRNA molecule and acts as an “attach here” signal for ribosomes during translation
What is modified guanine (G) nucleotide termed as?
5’cap
What is added to the 3’ end consisting of 30-300 adenine (A) nucleotides?
Poly(A)tail
Whats the non coding’s called?
Introns
Whats the amino acid coding sequence called?
Exons
When introns are removed and exons are joined together what’s this called?
RNA splicing
What is a codon?
A set of 3 nucleotides.
What does AAA and AAG amino acids stand for ?
Lysine
What is a nonsense nutation?
When a codon is changed to code for a stop codon instead of an amino acid.
List the 3 stop codons
UGA- You Go Away
UAA- You Are Away
UAG- You Are Gone
What is a missense mutation?
When a new, different amino acid is plugged into the polypeptide chain
What ca these missense mutations have a major effect on?
Protein function and can affect phenotypes
What 2 polar R groups are very similar?
-Glycine
-Serine
Name the double muscling gene?
Myostatin gene
What can alter the reading frame of the mRNA sequence?
Insertion or deletion, occurring in exon sequences can alter it.
Who discovered the first mutation?
Hermann Muller
List chemicals that can cause mutations:
-Nitrous acid
-Ethyl methanesulfase
-Acridine
Base- analog mutagen
Nucleotide analogs
Name radiation Mutations:
-Radon gas
-UV radiation
From Charles Darwin’s “origin of species” what is
Central idea 1
Central idea 2
1- Descent with modification
2- Natural selection
What is the ‘tree of life’ based on?
Molecular information
What is phylogenies?
Evolutionary history or development of a group of organisms
What is a phenotype determined by?
-genotype
-environmental factors
Who developed the field of population genetics?
Sewall wright, Ronal’s a fisher, jbs halfane
What is the Hardy Weinberg Theorem?- def
The genetic structure of a non-evolving population
Hardy Weinberg Equation
p^2 + p^2 +2pq^2 = 1
List an adaptive case of microevolution
Natural Selection
List non adaptive cases of micro evolution
-Genetic drift
-Gene flow
-Mutation
-Non-random mating
What is a ‘founder effect’
Also give an example
Is is genetic drift in a new colony
-Retinitis Pigmestosa
What mutations are transmitted to future generations?
Mutations in germ-line cells
Name an example of ‘positive selection’ in human populations
the Duffy Blood group
‘ duffy gene ‘
Fy^o allele in duffy blood group
and
Fy^a allele in duffy blood group
Fy^o=
Confer resistance to malaria parasite
Fy^a=
Susceptibility to malaria
Plasmid- definitions
small, self replicating DNA molecule found in bacteria used as a cloning vector
What is the 4 step process of DNA agarose gel electrophoresis?
1- DNA migrates from negative to positive electrodes.
2- Smaller DNA molecules migrate faster than larger DNA molecules.
3- UV light is used to visualise the DNA bands in the gel.
4- Ethidium bromide binds to the double strand DNA
What is the DNA ligase used for?
it is used to seal the DNA sugar phosphate back bone between the cloning vector DNA and the DNA insert during molecular cloning.
What’s the temperature steps for the PCR cycle?
Denature step temp= 94
Primer annealing step= 55
Enzyme extension step= 72
What components are used for a typical PCR reaction?
-enzyme
-nucleotides
-primers
-Taq DNA polymerase enzyme
-dATP, dCTP, dTTP nucleotides
-Synthetic single stranded oligonucleotide DNA primers
What does the Sanger DNA sequencing method use?
Dideoxynucleotide triphosphates (ddNRPs)
What does LacZ allow?
It allows bacterial colonies carrying DNA insert to be selected during the molecular cloning process based on their ability to metabolise the sugar X gal
What is the amplicon?
It is a target region of a genome that is amplified during the PCR
What is 5’-GAATTC-3’
It is the palindromic DNA sequence
What is 3’-CTTAAG-5’
Restriction sequence for EcoRI
What is the function of the DNA polymerase ?
It catalyses the synthesis of new DNA molecule using a template DNA strand (i.e. Transcription)
Example of incomplete dominance:
Red snapdragon plant crosses with a white snap dragon plant and produce pink offspring
What cells have no nuclear membrane?
Prokaryotic cells
Homozygous - what is it?
A diploid organism with a pair of identical alleles
What does the chromatin in eukaryotic cell nuclei consist of?
DNA and Protein
What is the phenotypic proportions of foals born if the stallion is mottled and the female mare is mottled?
50% mottled overo foals, 25% solid colour foals, 25% white stillborn foals
What is the phenotypic proportions of foals born if the stallion is mottled and the female mare is mottled?
50% mottled overo foals, 25% solid colour foals, 25% white stillborn foals
What is a Thymine always paired with?
Adenine via 2 hydrogen bonds
What is the chromosomal combinations during mitotic cell division of ovine haploid cells that have 27 haploid cells?
134,217,728 (i.e. 2^27)
What is the genotype of an X linked gene in male mammals ?
Hemizygous
What animal has gone through 2 population constructions that led to reductions in genetic variation?
Cheetah
What will an evolutionary founder event increase?
Genetic drift
What are introns?
They are removed from transcribed protein coding RNA during mRNA processing in eukaryotes
Does exposure to a genetic field cause mutation?
No
What is transcription carried out by?
RNA polymearse
What is a ribosome made up of?
Protein and RNA
What does the structure of DNA contain?
-Hydrogen bonds
-Purine
-Pyrimidine
What does a retroviral enzyme reverse transcriptase do ?
Transcribes a DNA molecule from a single stranded viral RNA template
What is the Sanger lab method used for determining?
The sequences of bases in a DNA molecule.
What is the method used to produce transgenic animals?
-Microinjection of foreign DNA into embryo pro nuclei
-Replacement of an oocyte nucleus with the nucleus of a transgenic donor cell.
-Use of modified retroviruses as vectors to carry genes into an embryo.
What is Agrobacterium Tumefaciens?
Bacterial species used to produce transgenic plants using recombinant TI plasmids
what does TI stand for?
Tumour Inducing
What VIT is in transgenic golden rice?
Vitamin A
What process does NOT occur in eukaryotic cell nucleus?
Translation
What is special about the AMP ^ R gene?
this is a gene that confers resistance to an antibiotic during bacterial cloning of recombinant DNA
Tell me about Codons?
-Consist of 3 nucleotides
-Never codes for more than 1 amino acid
-Basic unit of genetic code.
What is the anticodon of a particular tRNA molecule complementary to?
corresponding mRNA molecule.
What does the combination of human genome consist of?
-Nuclear genome
-Mitochondrial genome
What is the size of a haploid human genome in base pairs?
3.2 giga base pairs
What is the anticodon of a particular tRNA molecule complementary to?
corresponding mRNA molecule.
Is heat a mutagent?
No
What does RNA polymerase synthesise?
mRNA
How many stop codons is there?
3
How many start codons is there?
1
Definition for semi conservative replication?
Model of DNA replication whereby two DNA strand parental molecules separate and each single strand then functions as a template for the new complementary strand
What is transfer RNA responsible for?
responsible for transferring correct amino acids as site of translation
What phase of the cell cycle is genetic material replicated?
S phase
Co-dominance- definition
Intermingling of two dominant genes
What is the pentose sugar in DNA called?
Deoxribose
What does ribosomes facilitate the translation of?
mRNA into a polypeptide
What will positive natural selection act to do?
Increase the frequency of favourable alleles in the population
The phenomenon is where some tRNA anticodons recognise two or more different codons, what is this called?
‘Wobble’
List the process of gene expression
DNA-RNA-Polypeptide-Protein
What animal is the workhouse of genetics?
Fruit fly
