ap bio unit 6 mcq progress check answers

1. Transformation experiment gel electrophoresis (Figure 1)

B — E. coli in lane B have been successfully transformed and contain additional genetic information.

2. Prokaryote vs eukaryote chromosome structure

D — Prokaryotes have a single circular chromosome; eukaryotes have multiple linear chromosomes.

3. Lynch syndrome inheritance

B — The individual has an increased risk of developing colon cancer.

4. Restriction enzyme gel electrophoresis comparison

D — Species A has more short fragments of DNA than species B does.

5. Semiconservative DNA replication

D — Each newly synthesized strand remains associated with its template strand.

6. Cycloheximide translation inhibition

C — CPM increases, plateaus when inhibitor is added, then increases again when inhibitor is removed.

7. Retrovirus infection mechanism

C — Reverse transcriptase produces DNA from viral RNA that integrates into the host genome.

8. UV radiation DNA damage

D — UV photons cause dimers to form, distorting DNA and causing replication errors.

9. Evidence tryptophan is a corepressor

D — When trpR is mutated, the operon is transcribed regardless of tryptophan levels.

10. Alternative splicing long-term effect

A — The cell will die because it cannot metabolize the substrate without enzyme A.

11. Enzyme 1 at replication fork

B — Enzyme 1 is DNA primase that synthesizes RNA primers on the lagging strand.

12. Regulation of TYR, TRP2, TRP1 genes

B — The genes may be on different chromosomes but are activated by the same transcription factor.

13. Why keratinocytes do not produce melanin

A — Keratinocytes do not express the genes encoding melanin-synthesizing enzymes.

18. miRNA inhibition of translation

C — Altering the miRNA binding site allows translation even when miRNA is present.

19. rRNA processing

C — Sections of pre-rRNA are removed and mature rRNA combines with proteins to form ribosomes.

20. Huntington’s disease inheritance

B — She inherited an allele with more than 40 CAG repeats from her father.

21. Replication bubble strand synthesis

C — Strand I is synthesized continuously; strand III is synthesized in segments.

22. Gene regulation by DNA sequences

B — Some DNA sequences interact with regulatory proteins to control transcription.

23. Cystic fibrosis mutation type

C — Deletion mutation causes a frameshift.

24. DNA base pairing chemistry

C — Hydrogen bonds join a purine to a pyrimidine.