Nucleotides & Nucleic Acids

• What are the monomers that make up DNA and RNA?

  Nucleotides

  
• What three components make up a nucleotide?

  Pentose sugar, phosphate group, nitrogenous base

  
• What type of sugar is found in DNA nucleotides?

  Deoxyribose sugar

  
• What are the four nitrogenous bases in DNA?

  Adenine, cytosine, guanine, thymine

  
• What type of sugar is found in RNA nucleotides?

  Ribose sugar

  
• What are the four nitrogenous bases in RNA?

  Adenine, cytosine, guanine, uracil

  
• What distinguishes purines from pyrimidines?

  Purines have a double ring structure

  
• Which bases are classified as purines?

  Adenine and guanine

  
• Which bases are classified as pyrimidines?

  Cytosine, thymine, and uracil

  
• What is the significance of the pentose sugar in nucleotides?

  It contains 5 carbon atoms

  
• How does deoxyribose differ from ribose?

  Deoxyribose has one fewer oxygen atom
• What forms the sugar-phosphate backbone of DNA and RNA?

  Alternating deoxyribose sugars and phosphate groups

  
• What is the process of forming a phosphodiester bond?

  Condensation reaction between nucleotides
• What is required to break down polynucleotides?

  Breakage of phosphodiester bonds
• What is ATP known as?

  The universal energy currency
• What is the role of ATP in cells?

  Transfers energy for cellular processes
• What is the structure of ATP?

  Adenosine with three phosphate groups

  
• What is the difference between adenosine and adenine?

  Adenosine includes a pentose sugar

  
• What is the process of DNA replication called?

  Semi-conservative replication

  
• What happens to DNA during semi-conservative replication?

  Each new DNA has one old and one new strand

  
• What are the steps involved in the Marmur preparation for DNA purification?

  1. Lyse cells to release DNA
  2. Use enzymes to remove proteins
  3. Precipitate DNA with organic solvent

  
• What equipment is needed for extracting DNA from onions?

  • Plastic syringe
  • Plastic funnel
  • Beakers
  • Test tubes
  • Stirrer
  • Knife
  • Washing-up liquid
  • Ice-cold ethanol
  • Protease enzyme
  • Filter paper
  • Water bath
  • Ice-water bath
  • Blender
• What is the role of washing-up liquid in DNA extraction?

  • Disrupts cell membranes
  • Releases DNA from cells
• Why is ice-cold ethanol used in DNA extraction?

  • Nucleic acids are insoluble in ice-cold ethanol

  
• What is the significance of the 3’ and 5’ ends of DNA strands?

  • Indicates directionality of the polynucleotide strands
• What is complementary base pairing in DNA?

  • A pairs with T (2 hydrogen bonds)
  • G pairs with C (3 hydrogen bonds)

  
• What is the structure of DNA described as?

  • A double helix formed by two antiparallel strands

  
• What is the importance of hydrogen bonds in DNA structure?

  • Hold the two strands together

  
• What is the result of DNA extraction from onions?

  • A white precipitate of DNA for analysis

  
• What is the role of protease in DNA extraction?

  • Denatures and removes proteins from DNA

  
• What is the significance of the DNA replication process?

  • Ensures daughter cells receive complete genetic information
• What does the term 'semi-conservative' refer to in DNA replication?

  • One old strand and one new strand in each molecule

  
• What is the role of enzymes during DNA extraction?

  • Facilitate the breakdown of cellular components
• What is the purpose of lysing cells in DNA extraction?

  • To release DNA from the cell nucleus
• Why is it important to cool the mixture during DNA extraction?

  • Prevents DNA breakdown from heat
• What is the significance of the sugar-phosphate backbone in DNA?

  • Provides structural support to the DNA molecule

  
• What is the role of blending in DNA extraction?

  • Breaks down cell walls to release more DNA
• What is the importance of the 60 °C water bath in DNA extraction?

  • Denatures enzymes that could digest DNA

  
• What is the purpose of filtering the mixture in DNA extraction?

  • Removes cell debris and membrane fragments

  
• What is the significance of the term 'polynucleotide' in DNA structure?

  • Indicates that DNA is made of many nucleotides