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Chapter 12. By: Cole, Symone and Mel. 12.1 : DNA. Grffith’s Experiment & Transformation Transformation is the process when the heat-killed bacteria had passed their disease-causing ability to the harmless strain Disease-causing bacteria = Dead Mouse Harmless bacteria = Lives
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Chapter 12 By: Cole, Symone and Mel
12.1 : DNA • Grffith’s Experiment & Transformation • Transformation is the process when the heat-killed bacteria had passed their disease-causing ability to the harmless strain • Disease-causing bacteria = Dead Mouse • Harmless bacteria = Lives • Heat-killed Disease causing bacteria = Lives • BUT when you mix heat killed with harmless = Dies Of Pnuemonia
Avery & DNA • Avery and other scientists discovered that the nucleic acid DNA stores and transmits the genetic information from one generation of an organism to the next • Bacteriophage- its a kind of virus that infects bacteria. To infect a bacteria the virus attaches to the cell and injects its genetic information. • Hershey & Chase did an experiment with viruses and radioactive markers. They concluded that the genetic material of the bacteriophage was DNA, not protein.
The Components & Structure of DNA • DNA is a long molecule made up of units called nucleotides
Summary Of Scientists • Griffith: Transformation • Avery: Determines that genes are composed of DNA • Franklin: studied DNA molecule by using X-Ray Diffraction • Watson & Crick: double helix structure of DNA • Brenner: Discover messenger RNA • Gilbert: methods to read the DNA sequence • Human Genome Project: completed attempt to sequence all human DNA
12.2 : Chromosomes & DNA Replication • Prokaryotic cells - DNA molecule are located in the cytoplasm • Chromatin: DNA and protein in chromosomes • Histones: a type of protein • Replication: When a cell duplicates its DNA • During replication, the DNA splits into two strands, and then produces two new strands, which serves as a template. • DNA polymerase: joins individual nucleotides to produce DNA molecules
12.3 : RNA & Protein Synthesis • Genes: coded DNA instructions that control the production of proteins in a cell • 3 types of RNA: Messenger RNA, Ribosomal RNA, and Transfer RNA • Transcription: a process when RNA molecules are produced by copying part of the nulceotide sequence of DNA into a sequence of RNA • Promoters: regions that the enzymes bind to
12.3... • Introns (nucleotide) & Exons (proteins) • Codon: consists of 3 consecutive nucleotides, they represent the different amino acids • Translation: when the cell uses info from the messenger RNA to produce proteins