24: Epigenetic Mechanisms Quizellenjmchenry2022-11-23T14:13:22-05:00 Please sign up for the course before taking this quiz. Genes can be made up of many different DNA sections that are spread out and must be spliced together.1 True False 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 What is the “methyl” group?1 COOH CH3 CH4 CH3-R What do nucleosomes/histones help to do?1 Translate proteins. Keep DNA organized. Replicate DNA. "Spell check" replicated DNA for errors. What does methylation do to DNA?1 Destroys "junk" DNA. Keeps the DNA strands closed so they cannot be transcribed. Opens DNA strands to promote DNA transcription. Replicates it. How many histones come together to make the nucleosome?1 2 4 12 8 MicroRNAs or miRNAs help to regulate gene expression by1 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. helping DNA polymerase to bind to DNA for gene transcription, therefore "upregulating" the gene. The “switches” on nucleosomes (histone spools) can be activated by all of these molecules EXCEPT:1 Acetyl (COCH3) Phosphate (PO4) Methyl (CH3) DNA polymerase What does “epi-genetics” roughly mean?1 "without/no genes" "outside of the genes" "within the genes" "before genes" When a gene is being used and being transcribed, we say it is being _______________.1 exposed modified silenced expressed 23: Mitosis (and DNA replication) Final Exam: lessons 1-24 Back to: 24: Epigenetic Mechanisms
