Heredity and Evolution - PowerPoint PPT Presentation

1 / 16
About This Presentation
Title:

Heredity and Evolution

Description:

Heredity and Evolution Chapters 1-12 II. Heredity and Evolution (25%) Heredity (8%)1.Meiosis and gametogenesis 2.Eukaryotic chromosomes 3.Inheritance patterns – PowerPoint PPT presentation

Number of Views:367
Avg rating:3.0/5.0
Slides: 17
Provided by: DavidS574
Category:

less

Transcript and Presenter's Notes

Title: Heredity and Evolution


1
Heredity and Evolution
  • Chapters 1-12
  • II. Heredity and Evolution (25)
  • Heredity (8)1.Meiosis and gametogenesis
    2.Eukaryotic chromosomes 3.Inheritance patterns
  • B. Molecular Genetics (9)1.RNA and DNA structure
    and function 2.Gene regulation 3.Mutation 4.Viral
    structure and replication 5.Nucleic acid
    technology and applications
  • C. Evolutionary Biology (8)1.Early evolution of
    life 2.Evidence for evolution 3.Mechanisms of
    evolution

2
Meiosis and Gametogenesis
  • Reduce chromo and increase variation
  • Male gamete female gamete zygote
  • Germ-line vs. somatic
  • Unique features of meiosis
  • Two divisions, one replication
  • Synapsis, crossing over at chiasmata
  • Reduction division - Anaphase I (segregation,
    indp asst)
  • Meiosis I still has doubled chromosomes
  • 4 haploid cells with variety
  • Parthenogenesis?
  • Errors -- nondisjunction aneuploidy
  • Downs (Trisomy 21)
  • Klinefelter, Turner, Jacob
  • Amniocentesis, Chorionic Villi Sampling
  • Karyotype of chromosomes only

3
Patterns of Inheritance
  • Mendel and the peas (success!)
  • Gene, allele, diploid, homozygous, heterozygous,
    genotype, phenotype
  • Law of Segregation
  • Diploid --- haploid --- zygote
  • Dihybrid
  • Law of Dominance
  • Stronger allele, weaker allele
  • Law of Independent Assortment
  • No linkage?? (crossing over)
  • Rr x Rr -- genotype 121, phenotype 31
  • R? -- testcross
  • RrSs x RrSs -- phenotype 9331
  • RrSsTtUu x RRSsttUu

4
Patterns of Inheritance
  • Non-Mendelian
  • Codominance -- equal
  • Incomplete -- blend
  • Multiple alleles -- blood type
  • Pleiotropic -- cystic fibrosis
  • Epistasis -- two step pathway
  • Environmental (nature vs. nurture)
  • Continuous variation polygenic
  • Sex-linked -- on X (hemop, r/g color, white eyes
    Drosophila)
  • Pedigrees - ID pattern of inheritance
  • Gene Diseases
  • Huntingtons,Tay-Sachs (ethinicity), PKU, Cystic
    fibrosis, sickle cell, hemophilia, red-green
    colorblind

5
RNA and DNA - Structure/Function
  • DNA experiments
  • Griffith - transformation
  • Avery and Hershey-Chase -- transforming factor
    DNA (viruses)
  • Chargaff (AT, GC, of purines (AG) pyrim
    (TC)
  • Franklin, Watson, Crick -- backbone,
    complimentarity, anti-parallel
  • Meselson-Stahl -- semi-conservative
  • DNA Structure - double strand of nucleotides
  • DNA Replication
  • Origin (multiple for eukary)
  • Enzymes!
  • Helicase
  • Need primer (RNA)
  • Single stranded binding proteins
  • Gyrase (topoisomerase)
  • Polymerases (III mainly, II is repair, I fills in
    gaps) -- synthesize 5-3, proofread
  • Ligase
  • Leading and lagging strand
  • Okazaki fragment loops back through
  • Telomeres end of chromosome, not replicated on
    lagging!

6
RNA and DNA - Structure/Function
  • One gene - one polypeptide?
  • Central Dogma
  • DNA -- RNA -- Protein (why?)
  • Gene, mRNA, tRNA, amino acid, ribosome
  • Reading frame 3 letters (codon, anticodon)
  • Code is universal
  • AUG, UGA, UAA, UAG
  • Wobble
  • Transcription -- RNA Polymerase (eukary, rmt)
  • Template strand (antisense), coding strand
    (sense)
  • Promoter - Initiation (complex of in eukary,
    TATA)
  • Elongation - synthesis in 5-3, no proofreading
  • Termination
  • Posttranscrip modif in eukaryotes
  • 5 cap protects/initiates transl. Poly A tail -
    protect, exit)
  • Alternative splicing - introns, exons, snRNPS,
    spliceosome

7
Translation
  • tRNAs carry amino acids (aminoacyl-tRNA
    synthases)
  • Initiation - tRNA binds to P site, A, E empty
    (complex of eukary)
  • mRNA binds, large subunit binds
  • Elongation, translocation, termination
  • Surface of thyla has photosystems (II and I)
  • (ETC) -- Energy received, split water, e-
    excited, e- transferred (loose energy when
    pumping H), energy received, e- transferred to
    NADP
  • H accumulate in thylakoid space, down electro to
    make ATP
  • Pro vs. eu
  • Eu have introns (archae), cap and tail
  • Pro have operons
  • Pro simultaneous transcrip/translate
  • Ribosome size (antibiotic target)
  • Mutations (random, variation)
  • Substitution, chemical modif, insertion,
    deletion, duplication, inversion,
  • Silent, missense, nonsense

8
Gene Reg
  • Transcript
  • Binding motifs allow gene recognition
  • Prokaryotes -- Operons
  • Inducible (lac) vs repressible (tryp)
  • Activators vs. repressors (both allosteric)
  • Eukaryotes
  • 1. packing/unpacking DNA
  • 2. transcription
  • 3. mRNA processing
  • 4. mRNA transport
  • 5. translation
  • 6. protein processing
  • 7. protein degradation

9
DNA Technology
  • Restriction Enzymes
  • Cut at restriction site
  • Genetic engineering
  • Vector, host
  • Cleavage, Recombinant, Cloning, Screening
  • Library of genes, cDNA expressed
  • PCR heat, cool, copy, repeat
  • Gene therapy, transgenic (agriculture --
    pesticide, herbicide, drought, N fixation
  • DNA Fingerprints
  • Gel electrophoresis process
  • RFLP - restriction fragment length polymorphisms
  • Plasmid mapping
  • Gene Maps -- crossing over, microarrays
  • Cloning
  • Stem Cells

10
Viruses
  • Envelope, Capsid and Nucleic Acid
  • Envelope impt for specificity
  • ss? ds? RNA? DNA?
  • Retrovirus
  • Reverse transcriptase enzyme
  • Lytic vs Lysogenic
  • Attach, insert, replicate, assemble, burst
  • HIV AIDS
  • RNA retrovirus, lysogenic (latent), CD4 helper T
    cells (macrophage)
  • Opportunistic infections
  • Influenza and vacines
  • Prions and Viroids

11
Natural Selection and Evolution
  • Process (Darwin and Wallace)
  • ACTS ON ORGANISM/phenotype
  • Inherited Variation (vs acquired Lamarck)
  • Competition
  • Natural Selection Force
  • Reproductive Success
  • Agents of Change
  • Mutation, Gene Flow, Genetic Drift, Nonrandom
    mating, Selection
  • Evolution acts on population
  • Change in Allele Frequency
  • pq 1, p22pqq21

12
Early Evolution
  • Oparin, Miller/Urey
  • Primordial soup (organic cmpds, no O2)
  • Abiogeneisis pro/ana/hetero
  • 2.5 bya
  • Adaptive radiation photo, aero (form ozone)
  • Endosymbiont
  • Mito 1st, Chloro 2nd
  • Self-replicate, own ribosomes, own DNA, own inner
    membrane
  • Biogenesis

13
Evidence for Evolution
  • Darwins finches
  • Adaptive radiation (islands are great)
  • Peppered moth (industrial melanism)
  • Artificial selection (livestock, dogs)
  • Fossil record
  • Relative dating vs. absolute (half lives)
  • Anatomy
  • Homology, imperfect structures, vestigial,
    analogy
  • Divergent vs convergent evolution
  • BIOCHEMICAL
  • Antibiotic/Pesticide today

14
Mechanisms for Evolution
  • Speciation (allopatric or sympatric)
  • Reproductive Isolation
  • Geographic isolation (river)
  • Ecological (on ground, in tree)
  • Temporal (time of year)
  • Behavioral (song)
  • Mechanical (structures)
  • Gamete Fusion
  • POST Hybrid inviability or infertility
  • Pace
  • Gradualism (slow accum over time)
  • Punctuated equilibrium (dramatic change, usually
    environmental)
  • Patterns
  • Directional, disruptive, stabilizing

15
Systemics and Phylogeny
  • Classification
  • DKPCOFGS (name genus, specie)
  • Phylogenic tree
  • How closely related and what order
  • Common ancestor, derived traits
  • Monophyletic, paraphyletic, polyphyletic
    (protists)

16
(No Transcript)
Write a Comment
User Comments (0)
About PowerShow.com