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•Exam #1 is Th 9/27 from 7:30 to 9pm •Homework #1 is due now •Bonus #1 is posted and due 10/25 Fig 8.11 DNA contains the information to make RNA and/or proteins. Protein • Alternative splicing produces related but distinct protein isoforms Fig 9.20 Luciferase Gene (from fireflies) Expressed in a Plant 100% 4.7% 0.34% 0.22% A processed mRNA ready for translation 5’ untranslated region Protects from degradation/ recognition for ribosome 3’ untranslated region Protects from degradation/ transport to cytoplasm Combinations of 3 nucleotides code for each 1 amino acid in a protein. Fig 9.6 The Genetic Code: 64 codons 20 amino acids 1 start codon 3 stop codons Fig 8.11 Translation involves different RNA’s Protein • rRNA folds up by intramolecular base pairing Fig 9.12 • Ribosomes are made of both RNA and protein Fig 9.11 • On the ribosome, the mRNA, tRNA’s, and growing polypeptide come together Fig 9.13 • The structure of transfer RNA Fig 9.7 Fig 9.14 Translation initiation sequences along with the start codon signals the start of translation • Translation initiation in eukaryotes Fig 9.16 The poly-A tail and 5’ cap are involved in translation initiation Fig 9.6 The Genetic Code: 64 codons 20 amino acids 1 start codon 3 stop codons Redundancy in codons means that some tRNAs bind to the codon via wobble Fig 9.10 mRNAs are usually translated by multiple ribosomes simultaneously In bacteria, transcription and translation occur simultaneously • Termination of translation by binding of release factor (a protein) to the stop codon Fig 9.18 • All protein interactions in an organism (C. elegans) compose the interactome Fig 9.22 RNA synthesis Protein post-translational modifications: activation, inactivation, destruction, and translocation Fig 14.1 What makes us who we are? Nature and Nurture Imprinting: exposure to movement sets “mother” X/Y chromosomes in humans: genes = traits Fig 4.4 Human Chromosomes Twin studies have been used to determine the heritability of various traits, but there are some caveats. Correlation of weight and relatedness Correlation of weight (BMI) % Biological siblings 34 Parents and children living together 26 Identical twins reared together 80 Identical twins reared apart 72 Fraternal twins reared together 43 Adopted children and parents 4 Unrelated children living together 1 *But food preference shows little genetic correlation The nature of environmental influences on weight and obesity: A behavior genetic analysis. Grilo, Carlos M.; Pogue-Geile, Michael F.; Psychological Bulletin, Vol 110(3), Nov 1991. pp. 520-537. And two books by Matt Ridley: Nature via Nurture (2003) and Genome: the Autobiography of a Species in 23 Chapters (1999) Intelligence Correlation of IQ Inheritance : The same person tested twice Identical twins reared together Identical twins reared apart Fraternal twins reared together Biological siblings Parents and children living together Parents and children living apart Adopted children living together Unrelated people living apart % 87 86 76 55 47 40 31 0 0 From two books by Matt Ridley: Nature via Nurture (2003) and Genome: the Autobiography of a Species in 23 Chapters (1999) When the environment is equal (everyone has access to resources), genetic differences are magnified. When environments are different (only a few have access to resources), environmental differences are magnified. Proof or disproof? Correlation of IQ Inheritance : The same person tested twice Identical twins reared together Identical twins reared apart Fraternal twins reared together Biological siblings Parents and children living together Parents and children living apart Adopted children living together Unrelated people living apart % 87 86 76 55 47 40 31 0 0 From two books by Matt Ridley: Nature via Nurture (2003) and Genome: the Autobiography of a Species in 23 Chapters (1999) Can we see a genetic basis for complex behaviors? Voles Prairie Montane • Monogamous • Nonmonogamous • Both parents care • Mother cares for for young young briefly Oxytocin and Vasopressin (hormones) Water/salt balance Contraction of womb and milk production Encourages bonding between individuals Hormones are molecules produced in one cell and signal another. Oxytocin and Vasopressin (hormones) Water/salt balance Contraction of womb and milk production Encourages bonding between individuals Voles Prairie Montane • Monogamous • Nonmonogamous • Both parents care • Mother cares for for young young briefly Voles Prairie • Monogamous • Both parents care for young Montane • Nonmonogamous • Mother cares for young briefly Same levels of oxytocin and vasopressin Hormones are molecules produced in one cell and signal another. Voles Prairie • Monogamous • Both parents care for young Montane • Nonmonogamous • Mother cares for young briefly Same levels of oxytocin and vasopressin • More receptors • Less receptors Voles Prairie Montane • Monogamous • Nonmonogamous • Both parents care • Mother cares for for young young briefly Same levels of oxytocin and vasopressin • More receptors • Less receptors Inject hormone into brain •? • ? Voles Prairie Montane • Monogamous • Nonmonogamous • Both parents care • Mother cares for for young young briefly Same levels of oxytocin and vasopressin • More receptors • Less receptors Inject hormone into brain • Monogamous • Nonmonogamous Voles Prairie Montane • Monogamous • Nonmonogamous • Both parents care • Mother cares for for young young briefly Same levels of oxytocin and vasopressin • More oxytocin • Less oxytocin receptors receptors Block receptors •? • ? Voles Prairie Montane • Monogamous • Nonmonogamous • Both parents care • Mother cares for for young young briefly Same levels of oxytocin and vasopressin • More oxytocin • Less oxytocin receptors receptors Block receptors • Nonmonogamous • Nonmonogamous Voles Prairie • Monogamous • Both parents care for young Montane • Nonmonogamous • Mother cares for young briefly Same levels of oxytocin and vasopressin • More oxytocin • Less oxytocin receptors receptors Increase levels of receptors (genetically) in ventral pallidum • Monogamous • Monogamous Voles Prairie • Monogamous • Both parents care for young Montane • Nonmonogamous • Mother cares for young briefly Same levels of oxytocin and vasopressin • More receptors • Less receptors Why might these voles use different reproductive strategies? Prairie voles Montane voles • Monogamous • Nonmonogamous • Both parents care • Mother cares for for young young briefly Why might these voles use different reproductive strategies? Prairie voles: Montane voles: Resource poor Resource rich habitat habitat • Monogamous • Nonmonogamous • Both parents care • Mother cares for for young young briefly