Revision Of Molecular Biology And Genetics Flashcards
(30 cards)
Rule describing complementary base pairing ratios.
Chargaff’s rule (A = T, G = C).
Which pyrimidine is found in both DNA & RNA?
Cytosine.
Most abundant chromatin form in interphase nuclei.
Euchromatin (~90 %).
DNA polymerase direction of synthesis.
5’ → 3’.
Disease from NER (nucleotide excision repair) defect.
Xeroderma pigmentosum.
First amino acid in eukaryotic translation.
Methionine (formyl-Met in prokaryotes).
Function of m⁶A RNA modification.
Regulates mRNA stability and translation.
Name the donor of methyl groups in DNA methylation.
S-adenosyl-methionine (SAM).
Hardy–Weinberg equation for two alleles.
p² + 2pq + q² = 1.
Founder effect is an example of which evolutionary mechanism?
Genetic drift.
Gene mutated in hereditary non-polyposis colorectal cancer (HNPCC).
Mismatch-repair genes (e.g., MLH1).
Oncogenic translocation t(9;22) yields which fusion gene?
BCR-ABL in CML.
AZT targets which viral enzyme?
Reverse transcriptase of HIV.
Drug Methotrexate inhibits what enzyme?
Dihydrofolate reductase (anti-folate).
Define epistasis.
Interaction where one gene masks expression of another.
Mechanism generating antibody diversity before antigen exposure.
VDJ recombination.
Type of alternative splicing where an exon is omitted.
Exon skipping.
Protein marking system for proteasomal degradation.
Ubiquitination (E1 → E2 → E3 cascade).
Typical inheritance of mitochondrial diseases.
Maternal.
Missense vs nonsense mutation.
Missense = AA substitution; nonsense = premature stop codon.
Which DNA form is left-handed helix?
Z-DNA.
Role of telomerase.
Adds TTAGGG repeats to chromosome ends.
Protein that senses DNA damage and arrests cell cycle at G₁/S.
p53 tumour-suppressor.
Example of autosomal recessive metabolic disorder.
Phenylketonuria (PKU).
