Double helix structure of DNA

• What is the name of the molecule shown on the left side of the image?

  Deoxyribonucleic Acid (DNA)
• What is the chemical structure of Cytosine?

  Cytosine
• What are the four main nitrogenous bases found in DNA and RNA?

  • Guanine
  • Adenine
  • Thymine (in DNA)
  • Cytosine
• What is the chemical structure of Adenine?

  Adenine
• What are the building blocks of DNA?

  Nucleotides
• What are the four types of nitrogenous bases found in DNA?

  • Adenine (A)
  • Thymine (T)
  • Guanine (G)
  • Cytosine (C)
• How do the nitrogenous bases in DNA form base pairs?

  • Adenine (A) pairs with Thymine (T)
  • Cytosine (C) pairs with Guanine (G)
  • These base pairs are held together by hydrogen bonds
• What is the name of the sugar molecule that makes up the backbone of DNA?

  Deoxyribose
• How do the chemical structures of the nitrogenous bases in DNA and RNA allow for base pairing?

  • Adenine pairs with Thymine (in DNA) or Uracil (in RNA) through two hydrogen bonds
  • Guanine pairs with Cytosine through three hydrogen bonds
  • This base pairing allows for the double helix structure of DNA and the complementary nature of DNA/RNA
• What direction does one DNA strand run in?

  5' to 3'
• What does the 3' end of a DNA strand end with?

  Sugar molecule
• What is the name of the nitrogenous base that replaces Thymine in RNA?

  Uracil
• What direction does the other DNA strand run in relation to the first?

  Opposite 3' to 5' direction
• What are the structural components of a DNA nucleotide?

  • Sugar (deoxyribose)
  • Phosphate group
  • Nitrogenous base (A, T, C, G)
• What is the purpose of the hydrogen bonds shown in part (a) of the image?

  They hold the two strands of DNA together
• If you wanted to observe the detailed surface features of a cell, which type of microscope would you use?

  Scanning electron microscope (SEM)
• How does the structure of DNA allow it to store and transmit genetic information?

  • Double helix structure
  • Complementary base pairing (A-T, C-G)
  • Ability to replicate and pass on genetic information
• What type of sugar is found in DNA nucleotides?

  Deoxyribose
• How do nucleotides relate to the structure of DNA?

  Nucleotides form the repeating units of DNA
• How does the structure of DNA differ from RNA?

  DNA has a deoxyribose sugar, while RNA has a ribose sugar
• What is the chemical structure of Guanine?

  Guanine
• What are the components of a nucleotide in DNA?

  • Phosphate group
  • Sugar molecule (deoxyribose)
  • Nitrogenous base
• How do the differences in chemical structure between DNA and RNA impact their biological functions?

  • DNA's deoxyribose and double-stranded structure allows it to effectively store genetic information
  • RNA's ribose and single-stranded structure allows it to carry genetic information and aid in protein synthesis
  • The differences in nitrogenous bases (thymine vs. uracil) also contribute to their distinct functions
• What groups alternate along the sugar-phosphate backbone of DNA?

  Sugar and phosphate groups
• How does the structure of DNA allow it to store and transmit genetic information?

  The base pair complementarity allows accurate replication, and the double helix structure provides stability and protection
• What are the base pairs in DNA and their hydrogen bonds?

  • A-T: 2 hydrogen bonds
  • C-G: 3 hydrogen bonds
• Which bases pair together in DNA?

  A pairs with T, C pairs with G
• How are the base pairs held together in the DNA double helix?

  • Hydrogen bonds between complementary base pairs
• Why are specific protein-DNA interactions essential?

  They are essential for gene regulation and DNA replication
• What are the base pairs that form the rungs of the DNA ladder?

  • Adenine (A) pairs with Thymine (T)
  • Guanine (G) pairs with Cytosine (C)
• What are the structural differences between the major and minor grooves in DNA?

  • Major groove: Wider, allows substantial protein binding
  • Minor groove: Narrower, limits protein interactions
• How does the structure of DNA allow it to store and transmit genetic information?

  The sequence of base pairs encodes genetic instructions
• What is the function of the grooves in DNA?

  They allow proteins to bind to DNA
• How do the bases (A, T, C, G) relate to the sugar-phosphate backbone?

  They project inward to form hydrogen bonds
• What are the components of the sugar-phosphate backbone in DNA?

  • Phosphate groups
  • Sugar (deoxyribose)
• What term describes the orientation of the two DNA strands?

  Antiparallel
• What does the numbering of DNA indicate?

  • Indicates carbon atoms on deoxyribose sugar
• What are the four nitrogenous bases that make up DNA?

  Adenine, Thymine, Cytosine, Guanine
• What does the term "antiparallel" refer to in DNA strands?

  Strands run in opposite directions
• How does the 5' to 3' orientation affect DNA structure?

  • Maintains stability of the double helix