Intro to Molecular Biology

• The non-virulent rough strain introduced to mice did not result in death
• The virulent smooth strain introduced to mice caused them to die
• The heat-killed smooth strain introduced to mice did not result in death
• The mixture of heat-killed smooth strain and rough strain introduced to mice caused them to die
• Removal of carbohydrate, lipid and protein still allowed the rough non-pathogenic form to transform but removal of nucleic acids did not cause transformation
• Labelling protein and DNA with radioactive substances

  • Phage infects bacteria with radioactive DNA, causing the bacteria to be radioactive
  • Phage with radioactive proteins infects bacteria with DNA, but the bacteria is not radioactive
• Requirements for DNA as Genetic Material

  • Stable and resistant to attack from compounds within the cell
  • The components carrying information cannot be modified
  • Protected against unwanted access
  • Backed up to enable repair
• Transcription and replication occurs within the nucleus
• Translation occurs in the cytoplasm
• Almost every cell in the body contains the entire genome
• The genome contains genes to code for every protein
• The Transcriptome = All of the RNA (transcripts) within the cell
• Messenger RNA is translated into proteins
• Ribosomal RNA and Transfer RNA are functionally involved in the translation process
• Micro RNA and small nuclear RNA have regulatory functions
• The Proteome = All of the protein within a cell
• Each cell has different requirements for proteins at different times
• Only eukaryotic cells have a nucleus
• Both prokaryotes and eukaryotes can have a cell wall
• Hydrogen bonds join complementary bases in DNA
• Phosphodiester bonds join sugars of nucleic acids