M250 EXAM 4 2026 PRACTICE TESTED QUESTIONS FINAL PAPER GRADED A+

M250 EXAM 4 2026 PRACTICE TESTED
QUESTIONS FINAL PAPER GRADED A+

⩥ Omega Mismatch.
Answer: Insertion, when it slips back, adding bp


⩥ Delta Mismatch.
Answer: When DNAP slips forward and deletes some base pairs


⩥ Mutagens.
Answer: Environmental factors that damage DNA


⩥ Benzopyrene.
Answer: dsDNA intercalating agent that distorts double helix


⩥ Methyl-nitrosoguanidine.
Answer: Chemical modification of a base


⩥ UV Light.
Answer: Pyramidine diner formation

,⩥ Ionizing radiation.
Answer: Base elimination by forming a free radical


⩥ Genotype.
Answer: The DNA sequence of a gene/chromosome


⩥ Phenotype.
Answer: The measurable or observable trait conferred by a gene,
mediated by proteins


⩥ Allele.
Answer: Version of a gene


⩥ Missense mutation.
Answer: A single base pair change that changes the codon to a different
amino acid


⩥ Nonsense mutation.
Answer: Single base pair change that changes the codon to a premature
stop codon


⩥ Silent mutation.

, Answer: A single base pair change that codes for the same amino acid
due to degeneracy


⩥ Frame shift Mutation.
Answer: Insertion or deletion of base pairs in an amount not divisible by
three. Completely changing the subsequent amino acids


⩥ DNA Repair Systems (4).
Answer: 1. DNA Polynerase proof reading
2. Methyl-directed mismatch repair
3. SOS response and excision repair
4. Recombination repair


⩥ MutS.
Answer: Recognizes and binds to DNA distortion


⩥ MutL.
Answer: Linker protein
Recruits MutH and MutS


⩥ MutH.
Answer: Endonuclease, bucks DNA near damaged base