Anthro 105.pdf - Anthro 105 1 Topicsu200b Gene Chromosome...

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Anthro 105 1/30/2018 1)Topics: Gene, Chromosome, DNA, Base, Allele A) Deoxyribonucleic Acid (DNA) B) Chromosome - Long strings of DNA coiled into a dense thick rod C) Gene - A section of the chromosome that makes proteins or regulates other genes D) Proteins - “Lego blocks” of your body → Genes make those proteins… or regulate other genes to turn them on/off to make more/less of a protein 2)Structure of DNA 3)How are genes inherited? DNA consists of deoxyribose sugar, phosphate group, and nitrogenous base. 3 Hydrogen bonds between G and C 2 Hydrogen bonds between A and T Steps for DNA Replication 1.Origin of DNA strand is seperated and primed by DNA helicase. 2.Primase attaches to the separated to start new strand. 3.DNA polymerase adds on complementary nucleotides. 4.DNA ligase fuses two strands together Transcription and then Translation 1.Transcription begins on TATTA box. This is the promoter region that signals transcription to occur. 2.RNA polymerase attaches and begins converting DNA to RNA. 3.Elongation occurs and additional nucleotides are added onto the mRNA. 4.Termination occurs when all the introns are cut out an a poly A’cap/tail is added. P - chromosomes condense and recombination occurs M - chromosomes are lined up on the metaphase plate A - chromosomes start being pulled apart by spindles T - cytoplasm reforms and the new cells are created
*Norm of Reactions:Describes the pattern of phenotypic expression of a single genotype across a range of environments 2/9/2018 1)Four Forces of Evolution: Evolution occurs when the alleles in a population change over time. (Usually through many generations) → New Alleles Arise, or Existing Alleles become more or less common → Alleles are different version of genes a) Mutation: “Only source of variation that we have” - Substitution - Insertion - Deletion b)Genetic Drift: Alleles may be lost through random or natural chance c)Gene Flow: Movement of 2 different populations carrying different types of alleles into the population. Alleles exchanged between populations. → May result in greater diversity d)Natural Selection: Alleles that improve fitness become more common. i)There must be variation in a trait. ii)The trait must be heritable (shaped by genes). iii)Variation in the trait must affect fitness. → If you meet the first 2 conditions its Genetic Drift → If you meet the 3rd condition its natural selection **Fitness: Probability of producing surviving offspring → Usually measured as the Number of Surviving offspring Produced. → Fitness is measured relative to othersin the population. 2)Evolution of Physical Traits A) Spandrels & Vestigial Organisms - Spandrels: Neutral traits that are by-products of selections for something else Example - Brain is used for language but also for Art and Religion.

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