DNA replication

• Who is the instructor for BMS2036?

  1. Sarah Bailey
• Where is Dr. Sarah Bailey's office located?

  27 AY 04
• What is the purpose of student feedback and consultation?

  To ask questions in small groups or 1-2-1
• When is the first consultation session for BMS2036?

  Thursday 26/09/24 13.00 – 14.00
• What is the role of DNA polymerase in DNA replication?

  To generate an exact copy of original DNA

  
• What are the two discrete sites of DNA polymerases?

  P site for polymerisation and E site for editing

  
• What happens to an incorrectly paired nucleotide during DNA replication?

  It is removed by the E site with exonuclease activity
• What is the consequence of failing to remove incorrectly paired bases?

  A mismatched pair is left in the DNA sequence
• What are the types of DNA repair mechanisms?

  • Nucleotide Excision Repair (pyrimidine dimer)
  • Base Excision Repair (deamination)
  • Mismatch Repair (replication errors)
• What happens when depurination occurs in DNA?

  A base is deleted without changing the sequence

  
• What potential effects can a base deletion due to depurination have on protein sequence?

  It can cause a frameshift mutation or premature stop

  
• What occurs when the sugar phosphate backbone of DNA is broken?

  • Single Strand Break Repair is initiated for single strand breaks
  • Double Strand Break Repair is initiated for double strand breaks
  • Non-Homologous End Joining (error-prone)
  • Homologous Recombination (no loss of nucleotides)

  
• Where does crossing over occur during meiosis?

  Prophase I
• What is the purpose of crossing over during meiosis?

  To generate genetic diversity
• What is independent assortment in genetics?

  • Traits on different chromosomes do not influence each other
  • Genes assort independently during gamete formation
• What are linked genes?

  Genes located physically close on a chromosome
• How does crossing over affect linked genes?

  It can separate linked genes during inheritance
• What are the terminologies related to inheritance of genes?

  • P = parental generation
  • F1 = first progeny
• What is the outcome of double stranded breaks in chromosomes?

  They allow chunks of chromosomes to translocate

  
• What genetic diseases can result from chromosomal translocation?

  Burkitt’s Lymphoma and Down Syndrome
• What is the format for human gene names?

  Capital letters and in italics
• What are some recommended resources for extra help?

  • Alberts et al. Molecular Biology of the Cell
  • Lodish et al. Molecular Cell Biology
  • Additional learning activities on Surreylearn
• When is the second student consultation session?

  Tuesday 15/10/24 13.00 – 14.00
• What is a chiasma?

  X-shaped connection during meiosis between homologous chromosomes
• What is chromosomal translocation?

  Abnormality where a chromosome breaks and reattaches to another chromosome

  
• What is conservation of sequences?

  Base sequence in DNA remains unchanged throughout evolution
• What is DNA ligase?

  Enzyme that joins ends of DNA strands with covalent bonds
• What is DNA helicase?

  Enzyme that opens DNA helix into single strands
• What is DNA primase?

  Enzyme that synthesizes RNA primer for DNA synthesis
• What is a double strand break (DSB)?

  Break in the phosphodiester bond between two nucleotides
• What is evolution?

  Process by which different kinds of living organisms arise
• What is the definition of conservation of sequences in DNA?

  Unchanged base sequences throughout evolution
• What occurs during crossing over in meiosis?

  Exchange of DNA between homologous chromosomes

  
• What is the function of DNA ligase?

  Joins ends of DNA strands with covalent bonds
• How does DNA polymerase function?

  Synthesizes DNA by joining nucleotides together

  
• What is the role of DNA helicase?

  Opens DNA helix into single strands
• What does DNA primase synthesize?

  A short strand of RNA on a DNA template
• What is a double strand break (DSB)?

  Break in the phosphodiester bond between nucleotides
• What is evolution?

  Process of organisms developing from earlier forms
• What is euchromatin?

  Transcriptionally active region of a chromosome