Epigenetics

    Cards (29)

    • What does gene expression refer to?
      When DNA or a gene is expressed
    • What processes are included in gene expression?
      Transcription and translation
    • How is gene expression controlled in eukaryotic organisms?
      Through epigenetics
    • What does epigenetics control in gene expression?
      Initiating or preventing transcription
    • What is the definition of epigenetics?
      Heritable change in gene function without DNA sequence change
    • What does a change in gene function mean in the context of epigenetics?
      Preventing gene expression
    • What causes changes in gene function in epigenetics?
      Environmental factors
    • What are some examples of environmental factors affecting epigenetics?
      Diet, stress, and toxins
    • What are chemical tags in the context of epigenetics?
      Tags that modify DNA or histones
    • What is the epigenome?
      A layer of chemical tags around DNA
    • How does the epigenome affect DNA structure?
      Affects coiling of DNA
    • What is heterochromatin?
      Tightly coiled DNA
    • What is chromatin?
      Loosely coiled DNA
    • What is the effect of increased methylation on DNA?
      Inhibits transcription
    • Why does increased methylation inhibit transcription?
      DNA becomes tightly coiled
    • Where do methyl groups attach in DNA?
      To the cytosine base
    • What is the role of acetyl groups in epigenetics?
      They bind to histones
    • How do acetyl groups affect DNA structure?
      They loosen DNA packing
    • What is the relationship between heterochromatin and transcription?
      Heterochromatin inhibits transcription
    • What causes euchromatin to allow transcription?
      Decreased methylation and increased acetylation
    • What are tumor suppressor genes?
      Genes that slow down cell division
    • What happens if there is a mutation in a tumor suppressor gene?
      Results in a non-functioning protein
    • What are two examples of tumor suppressor genes linked to breast cancer?
      BRCA1 and BRCA2
    • What effect does hypermethylation have on tumor suppressor genes?
      Turns off the gene
    • What does hypomethylation lead to in oncogenes?
      Permanent activation of the gene
    • What is the consequence of hypermethylation in tumor suppressor genes?
      Excess cell growth and division
    • What do oncogenes do?
      Trigger mitosis to occur
    • What are the key concepts of epigenetics related to cancer development?
      • Tumor suppressor genes slow down cell division
      • Mutations in tumor suppressor genes can lead to cancer
      • Hypermethylation can switch off tumor suppressor genes
      • Hypomethylation can permanently activate oncogenes
    • What are the effects of methylation and acetylation on DNA structure and transcription?
      • Increased methylation: DNA tightly coiled, transcription inhibited
      • Decreased methylation: DNA loosely coiled, transcription allowed
      • Increased acetylation: DNA loosely packed, transcription allowed
      • Decreased acetylation: DNA tightly coiled, transcription inhibited
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