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