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