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• What is the central dogma of molecular biology?

  Information transfers from nucleic acids to proteins
• What is the direction of RNA translation into protein?

  Unidirectional
• What must genetic material do?

  Contain complex information and replicate faithfully
• What is the role of RNA in genetics?

  Bridge between genes and proteins
• What is transcription?

  Synthesis of RNA using DNA information
• Where does translation occur?

  Ribosomes
• What does translation produce?

  A polypeptide using mRNA information
• What are the key definitions related to genomes?

  • Genome: Complete set of genetic instructions
  • Universal coding system for genetic information
  • RNA as a bridge between genes and proteins
• What is the structure of nucleic acids?

  Polymers composed of nucleotides
• What are the nucleotides in DNA?

  G, A, T, C
• What links nucleotides in a DNA strand?

  Phosphodiester bonds
• What gives DNA its polarity?

  Phosphodiester bonds of the DNA
• What is the structure of DNA?

  Antiparallel double-helix
• What is the diameter of the DNA double helix?

  20 Å
• How many base pairs are there per turn of the DNA double helix?

  10 base pairs
• What are the major and minor grooves in DNA?

  Wide and narrow grooves in the double helix
• What dictates the specific base pairing in DNA?

  Base structures of nucleotides
• What are Chargaff's rules?

  A = T and G = C in organisms
• What are the differences between DNA and RNA?

  • DNA: Double-stranded, deoxyribose, A, T, G, C
  • RNA: Single-stranded, ribose, A, U, G, C
• How is DNA organized in the cell nucleus?

  DNA is packed with histones into chromatin
• What are nucleosomes?

  Complexes of DNA and histones
• What are euchromatin and heterochromatin?

  Open and closed conformations of chromatin
• What factors affect chromatin remodeling?

  Histone variants and modifications
• What is the length of DNA when stretched out?

  2 meters
• What is the role of organelle DNA?

  Some organelles have their own genome
• What is the first organism to have its genome sequenced?

  Haemophilus influenzae
• What is the process of DNA replication?

  Separation of strands and synthesis of new strands
• What is semiconservative replication?

  Each strand acts as a template for synthesis
• What initiates DNA replication?

  Origins of replication
• What is the direction of DNA replication?

  5’ to 3’ direction
• What is the role of DNA helicase?

  Opens the DNA helix by breaking bonds
• What does primase do in DNA replication?

  Synthesizes short RNA primers
• What is the role of DNA polymerases?

  Adds dNTPs to the growing DNA strand
• What happens to dNTPs during DNA synthesis?

  They lose two phosphate groups
• What is the leading strand in DNA replication?

  Continuously synthesized DNA strand
• What are Okazaki fragments?

  Short fragments synthesized on the lagging strand
• What is the role of DNA ligase?

  Joins ends of Okazaki fragments
• How do DNA polymerases ensure accuracy?

  Proofreading and exonuclease activities
• What happens if errors in DNA replication are uncorrected?

  They can lead to mutations
• What are telomeres?

  Special nucleotide sequences at DNA ends