Organisms and their environment II BIOL1123B2

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Organisms and their environment IIBIOL1123B2
Approximate breakdown Molecular genetics 30-35
Population Genetics 10-15 Evolution 50-60
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The Process of Science
Worldview lectures and documentary

• Observation
• Question
• Logic if ... then...
• Hypothesis H0 (no difference between observed
  and expected) and H1 (observed and expected are
  different)
• Experiment
• Result reject or accept hypothesis
• alternative hypotheses
• Remember proof in science is impossible

3
Molecular Genetics

• examined the sequence of discoveries which led to
  our current understanding of molecular genetics.
  Understand the science behind these discoveries.
• Techniques of gene technology.
• Applications

4
Sequence of events.

• 1857 - Darwin - Characteristics of parents
  passed on to young.
• 1869 Friedrich Miescher discovered nuclein
  (DNA)?
• 1882 Walther Flemming Chromosomes
• 1920s - Levene DNA is a polymer (scaffolding)
  (tetranucleotide theory)?
• 1928 Griffith transforming principle
• 1930s Hammerling Acetabularia transplant
• 1941 Beadle and Tatum one gene one enzyme
  hypothesis
• 1944 Avery DNA, not protein, responsible for
  transforming principle

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Sequence of events. Contd.

• 1952 Hershey and Chase confirmed Averys
  results using
  bacteriophages.
• 1952 Briggs and King nuclear transplant exp.
  in frogs
• 1953 Rosalind Frankling x-ray diffraction of
  DNA
• 1953 Watson and Crick DNA model
• 1953 Sanger amino acid sequence for Insulin
• 1955 Chargaff AT and GC

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• Rosalind Franklin x ray diffraction
• Watson and Crick double helix
• Meselson-Stahl DNA replication is
  semiconservative
• Ingram single amino acid substitution can
  change the action of the protein.
• DNA replication leading and lagging strands,
  origin of replication
• proteins are linear sequences of amino acids
• Genetic code 3 base codons
• Transcription translation

7

• mRNA, tRNA and rRNA
• Introns and exons
• Gene Technology
• Phages and plasmids
• Restriction endonucleases sticky ends
• Gel electrophoresis
• DNA libraries
• Polymerase Chain Reaction (PCR)?
• DNA sequencing (dideoxyribonucleic acid)

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Population Genetics

• - population? genepool- locus, alleles, number
  of alleles per locus- gene, allele and phenotype
  frequency- Hardy-Wienberg Equilibrium- 2
  alleles pq1 p22pqq21
• - 3 alleles p1p2p31
• p12 2p1p2 2p1p3 p22 2p2p3 p32 1-
  gene flow, founder effect, genetic drift,-
  inbreeding, bottleneck

9
Evolution

• Darwin, Theory of natural selection- inherited
  variation and natural selection- influenced by
  Geologists - how?- variation, polymorphism-
  types of selection- mimicry- sexual selection
• Evidence for evolution- fossil record-
  sequences of morphological change- molecular
  evidence and morphology

10

• phylogeny and ontogeny
• Species definitions- evolution is a dynamic
  process, taxonomy is static- Linnaeus binomial
  nomenclature
• systematics phylogenetics, - Cladistics,
  (clade, synapomorphy, cladogram)- shared derived
  characters.

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• Evolution
• New species, sympatry allopatry
• Selection, individual, sexual, kin
• Divergent, stabilizing, directional
• Ring species
• Reproductive isolating mechanisms-Pre and post
  zygotic
• Evolution and geological time periods
• Kingdoms, domains,
• Evolution of sex gametophyte and sporophyte in
  algae and plants

12

• Evolution of Humans documentary.
• Kingdom Animalia
• Taxa covered by students