BIOL 3451 1st Edition Lecture 1 Outline of Last Lecture I. This was the first lecture.Outline of Current Lecture I. Genetics Has a Rich and Interesting HistoryII. Genetics Progressed From Mendel to DNA in Less Than a CenturyIII. Discovery of the Double Helix Launched the Era of Molecular GeneticsIV. Development of Recombinant DNA Technology Began the Era of CloningV. The Impact of Biotechnology Is Continually ExpandingCurrent LectureI. 1.1: Genetics Has a Rich and Interesting History• Few significant ideas were put forward to explain heredity during prehistoric times• 1600–1850: The Dawn of Modern Biology– William Harvey: Theory of Epigenesis• Structures like body organs aren’t present in the early embryo and are formed later– Schleiden and Schwann: The Cell Theory (1830)• Every living thing is made up of cells– Charles Darwin: Theory of Evolution• Rode on HMS Beagle- how he created theory of evolution through observation • published The Origin of Species (1859)• Existing species arose from other ancestral species by descent with modification• Natural selection: driving force for evolutionary change• Also proposed by Alfred Russel WallaceII. 1.2: Genetics Progressed From Mendel to DNA in Less Than a Century• Mendel– transmission of genes between generations– worked with peas and used quantitative data (1st to do this!)• Mitosis: 2 daughter cells each receive a diploid (2n) set– Meiosis: resulting cells (gametes) are haploid (1n); half # of chromosomes • Chromosomal theory of inheritance: inherited traits are controlled by genes residing on chromosomesThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.• Genes transmitted through gametes (maintains genetic continuity)• Mutations – produce alleles of a gene– source of genetic variation• Genotype: set of alleles for a given trait • Phenotype: expression of the genotype (observable trait)• DNA is the carrier of genetic information (not protein)– Research of Avery, MacLeod and McCarty: 1944III. 1.3:Discovery of the Double Helix Launched the Era of Molecular Genetics• DNA: antiparallel, double-stranded helix– Monomer: nucleotide of a sugar (deoxyribose) bonded to a phosphate and bases(A,C,T,G) – Nucleotides form A–T and G–C base pairing across the helix (Figure 1.6)• RNA is similar to DNA, except that:– usually single-stranded – has uracil (U) instead of thymine (T)– sugar in RNA nucleotides is ribose instead of deoxyribose– DNA more stable than RNA• DNA to RNA: transcription• RNA to protein: translation (Figure 1.7)– Central dogma of genetics• Genetic code: triplet nucleotides present in mRNA• Each triplet encodes for insertion of a specific amino acid into a growing protein chain• When protein is made, its action or location in a cell plays a role in producing a phenotypeIV. 1.4: Development of Recombinant DNA Technology Began the Era of Cloning• 1970s: restriction enzymes in bacteria that cut viral DNA at specific sites• allowed the advent of recombinant DNA and cloning (Figure 1.10)V. 1.5: The Impact of Biotechnology Is Continually Expanding• Biotechnology– used for the genetic modification of crop plants (Table 1.1)• increased herbicide, insect, and viral resistance (by putting in proteins)• nutritional enhancement– Gene therapy and genetic testing for medicine– molecular basis for hundreds of genetic disorders is known (Figure