Please enable JavaScript.

Coggle requires JavaScript to display documents.

Seeds, Flowers, and Heredity, b6NKYlgGS0ehPSM9G8CN_F9BE88F7-5719-4DFE-B49E…

- - - - Elkinsia polymorpha
        
        born within cupules
      - Pseudosporogonites quadrapartitus
        
        small, collarette-like cupules bearing a single ovule
      - Late Devonian
      - Primitive ovule
        
        Lobate integuments
        
        Free from nucellus/megasporangium
        
        Moresnetia zalesskyi
        
        8-10 lobes fused at chalaza and widely separated
  - - - Heterospory
      - Protection
        
        fusion of telome to form Integument
      - Pollen capture
        
        Pollen chamber
        
        Micropyle
      - Nucellus
    - - Complete enclosure of megasporangium within integument
      - Increased Protection:
        
        Desiccation
        
        Herbivory
      - Stamnostoma huttonense
  - - - Sperm:
        
        development within
        
        rely on water for swimming to archegonia
        
        flagellated
    - - Dispersal no longer requires water
      - Exine prevents desiccation
      - Some with air bladders
        
        Transport by wind
    - - Can be a lengthy process from pollination to fertilization
  - - - Enabled colonization of drier upland habitats
        
        Enabling advanced reproductive traits (pollen drops entrap pollen)
- - - - Ancestral Flower (Angiosperm)
        
        Features:
        
        Based on molecular data
        
        Bisexual
        
        Gynoecium
        
        5+ Carpals
        
        Androecium
        
        Radially Symmetric
        
        Multiple Whorls of Petals
      - First Flower Fossil
        
        Archaefructus Sinensis
        
        Likely Characteristics:
        
        Herbaceous
        
        Aquatic
        
        Over 124.6 Billion Yrs Ago
      - "Sister" Flower
        
        Most primitive extant
        
        all flowering groups
        
        Family: Amborellaceae
        
        Genus: Amborella
        
        understory shrubs or small trees
        
        Order: Amborellales
        
        Species: Amborella trichopoda
        
        based on molecular phylogenetic analyses
        
        Dioecious
        
        Male plants
        
        Female Plants
      - General Trends
        
        Flowers are Indefinite in number of parts
        
        Spiral Arrangement
        
        Ovary Superior
    - - Complete Flower (Perfect)
        
        All 4 Floral Appendages:
        
        Sepals, Sterile
        
        Petals, Sterile
        
        Stamens, Male
        
        Carpels, Female
        
        Hermaphroditic
      - Incomplete Flower (Imperfect)
        
        Lacks at least one appendage/whorl of sexual organs
      - Appendages:
        
        Sepal
        
        outermost
        
        modified leaves that surround maturing parts
        
        protects bud as it develops
        
        may be colorful
        
        Collectively: Calyx
        
        Petals
        
        above sepal on receptacle
        
        Leaf like but contain pigments other than Chlorophyll
        
        Collectively: Corolla
        
        attract pollinators
        
        Absent in wind pollinators
        
        Perianth
        
        Stamens
        
        above Petals
        
        Parts:
        
        Anther
        
        Microsporocytes (2n)
        
        Meiosis
        
        1 more item...
        
        Supporting Filament
        
        Collectively: Androecium
        
        Carpals
        
        Collectively: Gynoecium
        
        Megasporophyll
        
        Structures:
        
        Style
        
        Elevates Stigma
        
        Stigma
        
        Catches Pollen Grains
        
        Ovary
        
        Contains placentae bearing ovules
        
        Ovule
        
        Following Fertilization, these mature into the seeds
    - - Carpel Position
        
        Whorls inserted relative to the Ovary
        
        Superior:
        
        Carpel above
        
        Hypogynous: Perianth and Stamens on receptacle beneath ovary
        
        Inferior:
        
        Receptacle surrounds Carpel
        
        Carpel below
        
        Half Inferior
        
        Perigynous: Perianth and Stamens adnate to calyx
        
        Epigynous: Perianth and stamens from top of ovary
      - Variation
        
        Inflorescence
        
        Taxonomic importance
        
        Various ways to ensure cross pollination
    - - Trait Modifications
        
        Major Traits:
        
        Color
        
        Requires Resource=Omit when unnecessary
        
        some in UV spectrum
        
        some more attractive than others
        
        Smell
        
        Signal Pollinators
        
        Common Chemicals:
        
        Benzaldehyde (almond)
        
        Linalool (Lavender)
        
        Limonene (citrus)
        
        Beta Ocimene (Green)
        
        may have scent glands
        
        using own preferences/sexual pheromones
        
        Shape
        
        Floral Symmetry:
        
        Actinomorphic:
        
        Radially Symmetric
        
        Zygomorphic:
        
        Irregular
        
        Bilateral
        
        Bloom Time
        
        Diurnal: Day Time
        
        Nocturnal: Night Time
        
        Rewards
        
        Oil
        
        Nectar
        
        Pollen
      - Types
        
        Abiotic
        
        Anemophily: Wind
        
        Hydrophily: Water
        
        Biotic
        
        Melittophily: Bee
        
        Psychophily: Butterfly
        
        Phalenophily: Moth
        
        Myophily/Sapromyophily: Fly
        
        Ornithophily: Bird
        
        Chiropterophily: Bat
        
        Cantharophily: Beetle
      - Fruits
        
        Fruit Formation:
        
        Ovary wall thickens and differentiates and related structures develop into fruit
        
        Pericarp:
        
        Exocarp
        
        Mesocarp
        
        Endocarp
        
        Accessory:
        
        any with accessory tissue
        
        besides ovary included in fruit
        
        Simple
        
        Single Carpel
        
        2+ united Carpel
        
        Aggregate
        
        Apocarpous Gynoecium
        
        Carpel retains identity in mature state
        
        Multiple
        
        Derived from an inflorescence
        
        Combined Gynoecium of many flowers
        
        Parthenocarpic:
        
        Fruit Development without:
        
        Fertilization
        
        Seed Development
      - Seed Dispersal
        
        Syndomes:
        
        Wind
        
        Wings
        
        Parachutes
        
        Lightweight Seeds
        
        Water
        
        Buoyancy
        
        Large Airspaces
        
        Animal
        
        Active
        
        seed passes through gut w/o harm
        
        Passive
        
        hooks, catches, on fur, hooves
        
        Self
        
        Gravity
        
        Exploding
- - - - Independent Assortment:
        
        During Metaphase I
        
        Orientation of bivalents is random
        
        During Metaphase II
        
        Orientation of sister chromatids is random
        
        possibilities are 2n (GENERALLY)
      - Crossing over
        
        During Prophase I
        
        Synaptonemal complex forms
        
        Mixes the genes present in homologous chromosomes
        
        Results in:
        
        new combinations not present in the chromosomes of the parental cells
        
        Usually at least one chiasma occurs between every pair of homologous chromosomes
      - Sexual Reproduction
        
        Advantages:
        
        Genetic diversity
        
        Bet-hedging to novel environments
        
        Multiple deleterious alleles can be bunched together and eliminated
        
        Escape host-parasite negative impacts
        
        Promotes heterozygosity
        
        Pollination
        
        Cross pollination
        
        Self pollination
    - - Principle of Independent Assortment
      - Principle of Dominance
        
        Each individual has a unique genotype
      - Principle of Segregation
        
        1) Alleles are segregated from one another during meiosis such that each gamete contains only one of the alleles
        
        2) Offspring inherits two alleles for a trait from each of its parents by inheriting homologous chromosomes
        
        Each gamete has an equal chance to inherit either one of the genes
      - Extensions to Mendel’s Principles
        
        Incomplete Dominance
        
        Phenotype of heterozygote is intermediate between those of parent homozygotes
        
        Snapdragons:
        
        Multiple Alleles
        
        Many populations have more than 2 alleles for a particular locus
        
        Mutations
        
        Changes in the genetic makeup of an individual
        
        Point Mutation:
        
        Single nucleotide change
        
        Chromosome Mutation:
        
        Deletion:
        
        Segments of chromosome are lost
        
        Duplication:
        
        Part of the chromosome has doubled
        
        Inversion:
        
        Piece rotates 180
        
        Translocation:
        
        Exchange of parts between 2 nonhomologous chromosomes
        
        Transposons:
        
        Movable genetic element
        
        Jumping genes
        
        No crossing over:
        
        Fail to mix alleles across homologs
        
        Chromosome inherited same as parent
        
        Only 2 gamete types possible rather than 4
        
        Polygenic Inheritance:
        
        Multiple genes for one character
        
        Phenotype is cumulative result of combined effects of many genes
        
        Most traits
        
        Epistasis:
        
        One gene interacts with another
        and may interfere or mask
        
        Linkage:
        
        4 haploid genotype but not produced in equal numbers
        
        Recombinants less abundant
        
        Parentals more abundant
        
        Pleiotropy:
        
        Single gene with multiple effects on the phenotype
        
        Inheritance of a single gene which visibly influences several traits
        
        Polyploidy:
        
        Having more than two copies (2n) of a chromosome
        
        Autopolyploid
        
        Failed meiosis
        
        Self fertilization
        
        Allopolyploid
        
        Meiotic error
        
        Mismatch during mating
        
        Second mating creates matched pairs
        
        Evolutionary significance
        
        Polyploid mask deleterious recessive alleles
        
        Relax selection pressure
        
        Common ancestor of seed plants
        
        Common ancestor of extant angiosperms