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- 1. Chapter 12: DNA and RNA with Steve and Joe
- 2. Griffith and Transformation Injected mice with disease causing bacteria and mice developed pneumonia and died. Wondered if bacteria produced poison. Heat killed bacteria and mice survived. Injected mice with heat killed disease-causing bacteria mixed with living harmless bacteria and mice developed pneumonia. Discovered that lungs were filled with disease causing bacteria.
- 3. Hershey and Chase and the structure of DNA Two American Scientist, who studied viruses and non-living particles. BACTERIOPHAGE, is a virus that infects and kills bacteria DNA is along molecule made up of units called nucleotides. A NUCLEOTIDE is made up of deoxyribose,phosphate group and nitrogenous base. Watson and cricks model of DNA was a double helix.
- 4. Chromosomes and DNA Replication Prokaryotic cells lack a nuclei and their DNA is found in the cytoplasm. Prokaryotic cells contain nearly all of cells genetic information. Eukaryotic DNA is packed tightly DNA that is tightly coiled around proteins are called HISTONES. Eukaryotic chromosomes that contain DNA/Proteins, packed around a substance called Chromatin Before cells divide, it duplicates DNA in process known as replication.
- 5. RNA Similar to DNA, RNA consists of a long chain of nucleotides. Three main differences between RNA and DNA The sugar in RNA is ribose instead of deoxyribose RNA is generally single-stranded RNA contains uracil in place of thymine There are three different types of RNA: messenger RNA, ribosomal RNA, and transfer RNA.
- 6. Transcription The process in which part of the nucleotide sequence of DNA is copied into a complementary sequence in RNA. During transcription, RNA polymerase binds to DNA and separates the DNA strands.
- 7. RNA Editing Introns, intervening sequences, are removed from RNA molecules transcribed from many eukaryotics before they become functional. The remaining portions, called exons, or expressed sequences, are then spliced back together to form the final mRNA.
- 8. The Genetic Code and Translation “ language” of mRNA instructions. A codon consist of three consecutive nucleotides that specify a single amino acid to be added to a polypeptide. The three bases on the tRNA molecule are called anticodon. Translation is the decoding of a mRNA message into a polypeptide chain.
- 9. Mutation Changes in the DNA sequence that affect genetic information Gene mutations result from changes in a single gene.
- 10. Gene Regulation It refers to the control of the timing of changes to the appearance of the functional product of a gene. A functional gene product may be an RNA or protein. The majority of known mechanisms regulate protein coding genes.