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