Biodiversity

biodiversity英音: [baiəudai'və:səti] 美音: [baiəudai'və:səti] 不可数名词: 生物多样性(维持着生态平衡的大量各种生物的共存)英英释义 the diversity of plant and ...

Biodiversity

• Biodiversity
  • Species diversity
  • Genetic
    • high
      • high resilience
      • potential for long term survival
      • Higher adaptiv capacity
  • Ecosystem
    • Terrestrial
      • Tropical forest/Grassland/Desert/Tundra
    • Aquatic
      • Wetland/Lake/River/Ocean
• Species
  • distinct life-forms/living things
• Classification
  • Animalia界
    • Chordata门
      • Mammalla纲
        • Carnivora目
          • Felidae科
            • Panthera属
              • Panthera pardus种
  • concepts to define
    • Biological species concept
      • a group of populations
      • have the potential to interbreed in nature
      • produce fertile offspring
      • Inapplicable
        • extinct organisms known only from fossils
          • Trilobite fossil
        • organisms that reproduce only asexually
          • Bacterium/Hydra
    • Morphological
      • based on physical traits(morphological characters)
      • Appliable
        • Asexual organisms
        • Fossils
      • Disadvantage
        • Subjectivity in deciding which traits to use
        • Males and females which looks so different
        • Dogs officially reconized breeds
    • Ecological
      • ecological role or niche
        • unique adaptations to particular roles in a biological community
          • what they eat
          • where they live
    • Phylogenetic
      • as the smallest group of individuals
        • shares a common ancestor
        • form one branch of the "tree of life"
      • trace the phylogenetic history by
        • morphology
        • DNA (Deoxyribonucleic Acid)
      • less restrictive than Biological Species concept
        • Breeding between different species does not pose a problem
        • Permits successive species to be defined
          • even if they have evolved in an unbroken line of descent,with contimuity of sexual fertility
      • Disadvantage
        • hard to define the amount of difference required to distinguish seperate species
• Naming of a Species
• Plant Diversity
  • vertebrates/invertebrates
  • Evolutional line
    • form lower oxigen atomasphere to higher oxigen atomasphere
      • Plastid origin
      • Unicellular green algae
      • Streptophyte algae
      • Mosses liverworts hornworts
      • Vascular plants
      • Seed plants
    • Made plants better suited for life on dry land and much more successful
  • What are plants
    • Autotrophic
      • Using CO2 as the source of carbon for organic compounds
    • Photosynthetic
      • using chlorophylls a and b
      • plas several accessory pigments
      • to capture solar energy
    • Generally non-mortile
      • Exceptions for male gametes
    • Presence of persistent embryonic tissue(meristem)
      • Capable of indeterminate growth throughout life
    • Development from multicellular embryos
      • a reproductive cell(ovum)
        • surrounded by nonreproductive tissue
  • examples
    • Bryophytes
      • seedless,non-vascular plants
        • with apical growth
      • lack true roots&leaves
      • No lignified cell wall
      • liveworts, hornworts, moss
    • fern
      • Seedless
        • vascular plants
      • fronds
        • fern leaves
      • stems of most are underground rhizomes
      • need air to carry spores for fertilization
    • gymnosperms
      • naked seed plants
      • conifers
        • with male and female cones
      • Ginkgo
        • living fossil
    • Angiosperms
      • with flowers and fruits
      • seed plants
        • monocots
          • monocots
            • embryos have a single seed leaf(cotyledon)
          • eudicots
            • embryos have two seed leaves(cotyledons)
      • coloniza terrestrial(land) and aquatic (water) habitats
• Plant-like protist
  • Eukaryotes
    • Lack many other structures of true plants
      • absence of roots, stems, or leaves
    • Some algae are motile
    • Single celled,colonial or mulicellular speciesFrom microscopic to large size
    • Contain chloroplasts that carry out photosynthesis
  • examples
    • Diatoms
      • frustule made of silica
        • single or form chain
      • consists of two halves,each containing a flat plate
      • generate aboul 20-50% oxygen on the planet
      • constitude nearly half of the organic materials found in the oceans
    • Dinoflagellates
      • Some are endosymbionts animals
        • coral reefs
      • Red tide causing species
      • some exhibit bioluminescence
• Animal Diversity
  • examples
    • Porifera海绵动物
      • Sponges
      • lack of true tissues
      • simple body plan
      • hermaphroditic(individual produces eggs&sperms)
      • mature sponges are sessile附着的
    • cnidaria刺胞动物
      • exist as polyp(珊瑚虫) or medusa(jellyfish)
      • simplest animal that show a division of labour among specialized tissues结构与功能的分化
      • have sting sells(cnidocytes刺细胞)
        • each armed with a nematocyst刺丝囊
      • radially symmetry辐射对称
      • example
        • corals
          • colonial with many identical polyps
          • reef builders
            • secreting calcium carbonate to form a hard skeleton
          • some catch plankton浮游生物 and fish using stinging cells
          • most obtain energy and nutrients from dinoflagellates that live within their tissues(zooxanthellae)
          • other corals do nat rely on aooxanthellae and can live globally in much deeper water
    • annelida环节动物
      • segmented worms
      • all annelids wxcept leeches蛭 have chitin-made bristles(setae)刚毛
      • three groups
        • oligochaetes
          • few setae
        • polychaetes
          • many setae
        • leeches
          • no setae
    • mollusca软体动物
      • second-largest phylum of invertebrates after the Arthropoda
      • body devided into visceral mass, foot and head
      • a mantle外套膜 with a significant cavity used for breathing and excretion分泌
      • presence of radula齿舌(except for bivalves)双壳类除外
      • many mollusca are covered by a shell made of calcium carbonate
      • phylun门
        • gastropoda腹足动物(snails蜗牛 sea slugs海螺)
        • cephalopoda头足动物squid乌贼octopuses
        • bivalvia双壳类动物clams蛤蚌scallops扇贝
          • many are filter过滤feeders
        • class bivalvia单壳类
          • single shell or no shell
          • diverse feeding modes
    • arthropods节肢动物
      • the largest phy;um in the animal kingdom
      • segmented animals with a hard exoskeleton&jointed appedages分节的附肢
      • grow by molting脱皮
      • phylum
        • arachnids蛛形纲
          • spider, scorpion蝎子, mite螨虫, tick虱子
        • centipedes蜈蚣
        • insects
          • ant, moth蛾, butterfly
        • crustaceans甲壳纲动物
          • shrimp and crab
    • echinoderms棘皮动物
      • have internal skeleton with calcium ossicles
        • in which spines project from them
      • many have an oral andaboral surface
      • slow moving or sessile on sea bottom
    • chordates脊索动物
      • notochord脊索动物
      • segmental body wall(devided shells)&tail muscles
      • dorsal hollow nerve cord背空神经索
      • perforated pharynx穿孔的咽喉
    • fishes
      • cartilaginous软骨的
      • bony
    • amphibians两栖动物
      • vertebrate脊椎动物
      • transition from water to land
      • with thin, scaleless skin, well supplied with blood vessels for gas exchange
      • adults of some species have saclike囊状的 lungs
      • larval幼年的 stage in water and adult stage in both water and land
    • reptiles爬行动物
      • vertebrates
      • tetrapods陆生
      • develop amniote有壳的 eggs
      • have scales/scutes鳞甲
      • ectothermic(cold blooded)
    • aves(birds)
      • vertibrates
      • feathers
      • endothermic(warm blooded)
      • lay amniote eggs
      • wings
        • not all birds can fly
    • mammals
      • with hair
      • produce milk
      • with placenta胎盘
      • with lung
      • endothermic
• seed
  • embryonic stage of the plant life cycle
  • consist of
    • embryo
      • a tiny plant that has a root, stem, and one or more leaves
    • endosperm
      • nutritive tissue of the seed
    • seed coat
      • protective covering
• Vascular tissue
  • xylem
    • transports water and dissolved minerals
    • from roots to the stem and leaves
  • phloem
    • transports dissolved sugars and organic compounds
    • from the leaves to the stem and roots
  • cambium
    • give rise to secondary xylem and phloem
• Biological Tree of life
  • A classification of living things based on
    • phylogenetic relationship
    • morphological differences
  • Related to concept of evolution
  • Linkages resemble tree
    • From a common origin(ancestor)
  • include extinct members
    • evidence as fossils
• Reproductive isolation
  • prevents menbers of different species from mating with each other and producing fertile offspring
  • prevents gene flow between species