The Basocs/fundamentals + mutations Flashcards
How does the allele for sickling and normal globin allele relate to malaria resistance?
If heterozygote you are malaria resistant
So allele for sickling is is dominant with respect to malaria resistance
How does the allele for sickling and normal globin allele
relate to bete globin isoform production?
They are codominant with reepct to beta globin production .
As both the beta subunit and sickling allele create both normal and abs normal isoforms
How does the allele for sickling and normal globin allele
relate to Red blood cell (RBC) count at high altitudes?
Homozygote for beta subunit mutation you get normal RBC at high altitude
Homozygote for sickling yo get v. Low RBC at high altitude
Heterozygote you get reduced RBC at high altitude
So the alleles are INCOMPLETELY DOMINANT to each other wit respect to RBC at high altitude
Which blood type is the universal donor A type O B type AB C type A D type B
Blood type O (which is recessive to A and B
Why…..
In a pedigree, a trait that appear in both sexes and doesn't skip generations describes A autosomal dominant B autosomal recessive C seX linked dominant D seX linked recessive
Option A please
E.. G huntingdon disease where at least one aren’t is affected
In a pedigree, a trait that appear in more in females and doesn't skip generations describes A autosomal dominant B autosomal recessive C seX linked dominant D seX linked recessive
Option C
Father’s do not transmit to sons (as they give the unaffected Y) but can pass o trait to daughter
E. G. Familial vitamin D rickets
The appearance of a third intermediate phenotype describes A codomiance B over dominance C incomplete dominance D under dominance
Option C
E. G having medium sized dots when you stated out with small and large dots
under and over dominance realte to the fitness of the heterozygote (advantage or disadvantage)
What is meant by a multiple allele
These alleles have polymorphic loci so there are multiple alles for a trait at Population level
E. G hair, eye skin colour
What is penetrance?
The propertion of individuals that display the expected phenotype in a population (with a specific genotype)
> usually alleles have 100% penetrance
A mutation is
A Any change is the DNA sequence
B Any change in the amino acid sequence
C Any heritable change in the DNA sequence
D Any heritable change in the amino acid sequence
OPTION C
IT IS inherited!
> random but mutagens can increase frequency
Which of these does a single base pair mutation not cause? (single polymorphism SP A Silent mutation B Missense mutation C Frame shift mutation D Nonsense mutation
OPTION C - caused by Insertion/deletion (INDEL)
what is the difference between transversion and transistion mutaiton
transistion is purine for purine (A-G)
tranversion is purine for pyrmadine (A -T)
…’ how many porgency are the parent type (non-recombinatn type)?
add up both the parent geotypes together
> bigger number
porgency = offspring
normal chromosome : A B C D E F G H mutant chromosome: A B E F D C G H A insertion B deletion C duplication D inversion E chromosomal fusion
OPTION D
‘’ C D E F’’ inverted!
> chromosomal fusion would mean an extra bit would be added (e.g. I J K )
What does the ABO locus encode? A glycosyltransferase B glycocalyx C transferrin D glycophorin a E glycosylamine
glycosyltransferase modifies the oligosaccharides on cell surface glycoproteins to form ABO blood groups.
Which of the following mutations is a transverse mutation?
ATTGAC -> GTTGAC
ATTGAC -> AGTGAC
ATTGAC -> ATTCGAC
ATTGAC -> ATCGAC
ATTGAC -> ATGAC
OPTION B
A - transition mutation (purine A substituted for purine G)
CORRECT B - transverse mutation (pyrimidine T substituted for purine G)
C- insertion mutation
D- transition mutation (pyrimidine T substituted for pyrimidine C)
E - deletion mutation
Sometimes damaged bases are excised and replaced with a template strand. This is used to remove pyramidine dimers formed by UV radiation. What repair mechanism is this? A homologous recombination B mis-match repair C Nucleotide excision repair D non homologus recombination E base excision repair
Nucleotide excision repair
> the whole nucleotide is removed
> look at that lovely poster
What condition would prevent independent assortment from occurring?
A Probability of inheriting one specific allele has not impact on effecting the heritably of another allele for a different trait
B There are at least two alleles for each of the traits of interest
C The organism you are using must have its full genome mapped
D The probability of inheriting one allele for one trait affects the probability of inheriting the other allele for another specific trait
OPTION D - epistasis? as that is NOT INDEPENDENT
A and B must be true for independent assortment to occur, C has no relation to independent assortment
disease causing allele has variable penetrance. what mean?
A allele is dominant
B severity of disease differs between individuals with different genotype
C allele is reccesive
D severity of diease varies between individuals with same genotype
E allele affects another allele
OPTION D
only for those with the SAME genotype
'' changes codeon for a specific aa to a codon for a different aa'' describes A silent mutation B mis-sense mutation C non-sense mutation D frame shift mutation
this is mis-sense
> nonsense is when the a stopcodon is made = trunchated protein
phildelphi chromosme is an exmaple of inversion mutation variable expressivity translocation genes and environment
translocation event
> between chromosome 9 and 22 creating a protien fusion product contributing to chronic myelogenus leukemia
what do ‘intercalating agents’ do?
squeeze between basepairs and recognised by DNA as a extra base so get INSERTED during dna replication
> frame shift mutation depending on how many are added (INDEL)
