24: Epigenetic Mechanisms Quizellenj2022-11-23T14:13:22-05:00 Please sign up for the course before taking this quiz. 1. What does methylation do to DNA?1 Replicates it. Destroys "junk" DNA. Keeps the DNA strands closed so they cannot be transcribed. Opens DNA strands to promote DNA transcription. 2. The “switches” on nucleosomes (histone spools) can be activated by all of these molecules EXCEPT:1 Methyl (CH3) DNA polymerase Acetyl (COCH3) Phosphate (PO4) 3. What is the “methyl” group?1 COOH CH4 CH3-R CH3 4. Genes can be made up of many different DNA sections that are spread out and must be spliced together.1 True False 5. The DNA in the nucleus contains every bit of information that any cell will ever need for the entire lifetime of the organism.1 True False 6. How many histones come together to make the nucleosome?1 4 8 2 12 7. What does “epi-genetics” roughly mean?1 "before genes" "outside of the genes" "without/no genes" "within the genes" 8. MicroRNAs or miRNAs help to regulate gene expression by1 helping DNA polymerase to bind to DNA for gene transcription, therefore "upregulating" the gene. binding to mRNA that shouldn't be translated by a ribosome, therefore blocking the product of the gene. binding to DNA polymerase and preventing it from binding to DNA strands, therefore "silencing" the gene. "cutting" up pieces of mRNA into little fragments so that they cannot be translated. 9. What do nucleosomes/histones help to do?1 "Spell check" replicated DNA for errors. Translate proteins. Replicate DNA. Keep DNA organized. 10. When a gene is being used and being transcribed, we say it is being _______________.1 expressed silenced exposed modified 23: Mitosis (and DNA replication) Final Exam: lessons 1-24 Back to: 24: Epigenetic Mechanisms
