Molecular Genetics

• The DNA double helix is held together by hydrogen bonds between complementary base pairs.
• What are the five bases?

  Adenine(A)

  Cytosine(C)

  Thymine(T)

  Guanine(G)

  Uracil(U)
• Who discovered the double helix of DNA?

  Crick Watson
• What two main parts make up a chromosome?

  DNA and Protein
• What is the function of the DNA helicase enzyme in the DNA replication process?

  Unwinds the double helix into separate strands
• What defines a 3 base code in DNA or mRNA

  Codon
• Base is deleted, shifts to the left

  Deletion (Frameshift)
• Base is added, shifts to the right

  Addition (Frameshift)
• One base replaces the other base

  Substitution
• The sequence codes to stop early

  Nonsense
• The wrong amino acid is coded for

  Missense
• How do DNA strands fit inside of a cell?

  Tightly coil around proteins called histones
• Function of DNA polymerase

  Bring the complementary bases to the new unwound strands of DNA
• Function of DNA helicase

  Unwinds the double helix into separate strands
• Function of DNA ligase

  “Glues” everything together so it can wind into a new double helix
• What is the central dogma of biology?

  DNA to RNA to Protein
• What holds the nitrogenous bases together in DNA and RNA?

  Hydrogen bonds
• mRNA


  Coded from DNA and leaves the nucleus to find the ribsome
• rRNA

  part of the ribosome
• tRNA

  Transports the amino acids to the ribosome where protein synthesis takes place