Presentation on theme: "Classification The evolution of Complexity: single cell prokaryote to multicellular eukaryotes."— Presentation transcript:
Classification The evolution of Complexity: single cell prokaryote to multicellular eukaryotes
Aristotle to Linneaus Taxonomy- classifying organisms, by placing them into taxa Binomial nomenclature is the system of assigning a scientific name to each species. Made up of genus and species. Canis lupus, Turdis migratoris, Felis catus Systematics- the study of biodiversity and its classification, create phylogenies Phylogeny- an organism’s evolutionary history, a phylogenetic tree
Modern Classification System 3 Domains 6 Kingdoms Phylum Class Order Family Genus Species 3 Domain Archea, Eubacteria, and Eukarya 6 Kingdom Archeabacteria, Eubacteria, Protista, Fungi, Plant, Animal GenusFirst part of Scientific name Species Second part of Scientific name
The Evolution of Complexity Earth is approximately 4.5 billion years old 1 st living things, prokaryotic bacteria cells are found in the fossil record dating 3.5 billion years ago 1 st eukaryotic cells appear in fossil record dating 2.1 billion years ago Between 635-530 million years ago the fossil record shows the diversity of algae and small animal like organisms
Origin of Life Spontaneous Generation: life from non-life was replaced with – Biogenesis Oparin’s hypothesis of the origin of life was tested by Miller and Urey, creating organic compounds like amino acids but not life Endosymbiosis- the hypothesis behind the evolution of eukaryotes from prokaryotes
What is a Virus?- nonliving… Composed of genetic material, RNA or DNA, and a protein coat Genetic material surrounded by a protein coat, must have a host cell in order to reproduce Life cycles: Lytic (kills host cell) or Lysogenic (incorporates DNA into host)
3 Domains 1.Archea 2.Eubacteria 3.Eukarya Bacteria once belonged to the same Kingdom, Monera, but through Molecular Biology and the study of evolution, Biologist realized they had critical differences and should be placed into their own category so the “Domain” classification level was created.
Archea and Eubacteria Archea Kingdom All prokaryotic single celled organisms. No Peptidoglycan in cell wall Most ancient and extreme They live in the harshest environments Methanogens (anaerobic), thermoacidophiles (hot) and halophiles (salty) Eubacteria Kingdom True bacteria, all prokaryotic single celled Have Peptidoglycan in cell wall Classified by their shape and gram staining Gram + have more peptidoglycan and stain purple Gram – have less peptidoglycan and stain pink
Shapes and Examples Sphere- Cocci, can occur in chains Streptococcus Pneumoniae which can cause strep throat or Scarlet fever, or grapelike clusters Staphylococcus aureus which can cause skin infections and Toxic Shock syndrome Rod- Bacillus ex Escherichia coli (E.coli), Lactobacilli which can cause tooth decay or one strain makes Sourdough bread, other bacilli can cause botulism, typhoid fever, and anthrax Spiral- Spirilla comes in 3 shapes 1. Vibro which is curved caused Cholera, 2. Spirillum (thick spiral), and 3. Spirochete (thin spiral) ex. Treponema pallidum causes Syphilis and another strain can cause Lyme disease
Images of bacteria Strep- chain Staph - cluster E. coli Syphilis and Cholera
Essential Bacteria: ecosystems depend on these small organisms Cyanobacteria- photosynthetic/producers, building blocks of most aquatic food webs Nitrogen- Fixing Bacteria- symbiotic relationship with plants, they help them absorb nitrogen from the soil. Helpful: fermentation, digestion, biotechnology, nitrogen fixing, decomposers, oxygen producers Antibiotics kill bacteria by destroying the cell wall, gram negative have an extra lipid layer that prevents the antibiotics from entering the cell.
Reproduction Bacteria reproduce asexually, binary fission Each bacteria has a single chromosome but can have additional DNA in the form of plasmids. Plasmids increase Bacterial genetic variation and contribute to Bacteria evolution Plasmids can be exchanged between different bacteria (even different species) by a process called conjugation. Plasmids can also be taken up by bacteria from their environment via transformation. Additional DNA recombination can be introduced via a bacteriophage, this is called transduction.
Review of Bacteria All bacteria: Reproduce asexually Single celled Have cell wall Single strand of DNA Some Bacteria: Autotrophic Heterotrophic Some move by flagella, slime, spiral motion Some produce endospores which allow them to go dormant during hostile conditions Some produce toxins
Kingdom Protista Kingdom of Mostly single celled organisms Categorized by their likeness to 3 other kingdoms All Eukaryotic some Autotrophic and some Heterotrophic
Algae- Plant like Protist Algae or Plant-like, Autotrophic, classified by pigment with no cell wall, come form elaborate colonies and multicellular structures (kelp and seaweed) Chrysophyta- Golden Algae ex diatoms Pyrrophyta- bioluminescent/glow ex. Dinoflagellates Euglenaphyta- ex Euglena Rhodophyta- red Phaeophyta- brown, seaweed and kelp Chlorophyta- green, ex Volvox, Spirogyra
Images of algae Volvox Spirogyra Red algae Seaweed Kelp Diatoms
Protozoa or Animal like Protist Protozoa or Animal-like, classified by mode of movement Sarcodina ex. Amoeba- move by pseudopodia “false foot” Ciliophora ex Paramecium- move by cilia, tiny hairs Zoomastigina ex Trypanosoma (African Sleeping Sickness) moves by flagella Sporozoa, are the parasitic animal like protista, include Plasmodium which causes Malaria
Images of Protozoa Amoeba Paramecium Trypanosoma
Fungus-like Protista Fungus-like are all Heterotrophic with no cell wall, absorbing nutrients directly through cell membrane Include Plasmodium or Slime Molds and Downy Mildews
Kingdom Fungi All Eukaryotic, multicellular, heterotrophs (saprotrophs or detrivores living off dead and decaying organisms or decomposers), cell wall made of chitin (type of protein), and classified by reproductive structures. Mycoses is the term for Fungal Infection, Fungus destroys the cells around the infection site, to fight fungal infection you have to destroy the cell wall Fungi are important part of an ecosystem because they recycle nutrients/ decomposers
Classifications of Fungi Club Fungi – Basidiomycota, Basidia, ex Mushrooms Sac Fungi- Ascomycota, Asci, ex. Truffles, Morels,Yeast, and Athletes Foot Fungus Zygote Fungi – Zygomycota, Sporangia, ex. Bread molds Imperfect- Deuteromycota, reproduce asexually, ex Penicillian Lichen- Mycophycophyta, symbiotic relationship between fungus and photosynthetic cells of cyanobacteria or algae.
Images of Fungi
Kingdom Plante Multicellular, Eukaryotic, Cell wall made of cellulose, Autotrophs, not capable of movement, reproduce sexually some produce spores and others seeds. Most have vascular tissues which include roots, stems, and leaves, and specialized tissues called xylem and phloem.
Plant evolution Evolved from green algae, 400-450 mya Evidence: they both… –Chlorophyll a, b, and carotenoids –Thylakoid membranes –Cell walls of cellulose –Stored carbohydrates as starch **Primitive plants were aquatic, but adaptations have allowed them to be successful on land.
Plant evolution cont’d Adaptations to terrestrial life –Cuticle (leaf)- keep water in –Stoma (leaf)- control gas exchange –Development of specialized tissues leaf, root, stem, root hairs, vascular tissue –Symbiosis with fungi and bacteria to increase nutrient uptake –Secondary growth- lateral meristem to thicken structures –Spores and seeds not dependent on water
Guard cells Pore Stoma 18 µm Leaf surfaces contain stomata Photosynthesis relies on CO 2 entering the leaf and O 2 leaving the leaf
Leaf cross-section CO 2 Carbon dioxide diffuses into leaves through stomata H2OH2O BUT: water also escapes through the stomata This is a PROBLEM!
Spore Producing Divisions of Plant 9 Phyla of Plants: can be divided into spore or seed producers Spore producers Bryophyta only nonvascular plants, ex moss and liverwort (gametophyte dominant stage of life cycle know as alternation of generations) Lycopodophyta ex. 1,000 species of Club and Spike moss Pterophytes 12,000 species of ferns, horsetails, and whisk ferns have compound leaves called fronds (dominant stage is the sporophyte)
Spore producing plant images
Seed producers Gymnosperms: reproductive structure is the cone, “naked seed” –Cycadophyta 130 species of these tropical plants –Ginkgophyta 1 species remains the Gingko tree –Coniferophyta 600 species of conifers, pine, spruce, cypress, juniper, fir –Gnetophyta 75 species of these arid/semi- desert dwelling plants
Seed producers Angiosprems - reproductive structure is the flower, seeds are surrounded by fleshy or dry fruit that ripen to encourage animals to disperse the seeds. 30,000 or more identified species maple, hickory, oak, aloe, roses, tulips, dogwood, magnolia, corn, beans, tobacco, apple tree, pecan tree 2 classes: Monocots – with one seed leaf or cotyledon and parallel veins on the leaf, orchids, lilies, grass, corn, grains Dicots- with two seed leafs and branched veins on the leaf, roses, peas, beans, and oaks
Seed producers- gymnosperms “Cone Bearers”
Seed plants- Angiosperm
Flowering Plant images Produce flowers and fruits (fleshy or dry)
Dry and Fleshy fruits Fruit is the mature ovary of the flower. It surrounds the seed and is often used to promote seed dispersal. Animals eat the fruit and seed and poop it somewhere else, this reduces competition with the parent plant.
Parts of a Flower Pollination- fertilization of the female gamete by the male gamete Flowers are designed to attract a pollinator, either by color, smell, or offer of food. Birds, insects, and mammals act as pollinator
Other Plant Info. Symbiotic relations ships: Plants and Nitrogen fixing Bacteria Flower patterns and scent attract pollinators Fruits promote seed dispersal by offering a sweet reward to animals.
Plant Adaptations: Tropism- plant activities controled by hormones – phototropism (light), geotropism (gravity), and thigmotropism (touch) specialized leaves (needles, spines, fuzzy, waxy) help reduce water loss in arid environments
Animalia multicellular, eukaryotic, no cell wall, heterotrophs, capable of movement, reproduce sexually, body symmetry (radial or bilateral) 9 Phyla- 8 invertebrate and 1 vertebrate
Invertebrate- Cnidarian Cnidarians- Stinging cells (nematocytes), radial symmetry, simple nervous system only stimulus and response, central cavity only one body opening, ex. jellyfish, coral, hydra, sea anemone
Invertebrate- worms Plathyhelmenthes: flat worms, only one body opening, three cell layers,ex. Tapeworm, Fluke, Planarian, Marine worms Nematode: round worms, first with two body openings, 3 cell layers, many parasitic, Heartworm, Roundworm, Vinegar Eel Annelid: segmented worms, two body openings, 3 cell layers, beginning of circulatory system, and digestive system (crop), ex. Earthworm and Leech
Worm images Plathyhelmenthes Nematode Annelid
Invertebrate Mollusk soft body, more complex body systems developing, eyes and nervous system, levels of communication beyond stimulus and response 3 classes Gastropod (snails and slugs), Cephalopod (squid octopus cuttlefish and chambered nautilus), Bivalve (oyster, clam, mussel, scallop)
Mollusk images BivalvesGastropodsCephalopods
Invertebrate- Arthropod jointed legs, exoskeleton, body segments (head, thorax, and abdomen), metamorphosis (complete or incomplete) 4 classes: Insect -6 legs (ant, grasshopper, beetle, bee, wasp) Arachnid -8 legs (spider, tick, horseshoe crab), Crustacean -10 legs (shrimp, lobster, barnacles, crayfish) Myrapods -many legs, centipede and millipedes
Invertebrate- Echinoderm Characteristics: spiny skin, complex regeneration capacity, found only in marine environments, radial symmetry, Examples: Sea urchin, Sand dollar, Starfish, Sea cucumber
Vertebrates- Chordata Chordate notachord, complex body systems, sexual reproduction (internal or external fertilization) 5 classes: Fish Amphibians Reptiles Birds Mammals
Fish Fish, moist skin covered in scales, gills to breathe, 2 chambered heart, cold blooded, 3 types: 1. bony ex Trout, Salmon, Bass, Catfish, Grouper, Tarpon. 2. jawless, ex. Lamprey and tunicates 3. cartilaginous ex. Sharks and Rays
Amphibian Amphibian, cold blooded, 3 chambered heart, born in water, develop lungs, smooth moist skin, ex. salamander, newts, frogs, and toads (only dry skin)
Reptile Reptile, dry leathery skin with scales, cold blooded, most have a 3 chambered heart, amniote/terrestrial eggs, ex. Lizards, snakes, turtles, alligator, crocodile
Birds Bird, warm blooded, 4 chambered heart, hollow bones, body with feathers
Mammal Mammal, warm blooded, 4 chambered heart, milk producers, body with hair/fur Placental (live birth), Marsupial (pouch) ex. Kangaroo, and Monotremes (egg) ex Platypus
Animal Form Body structure and development
Fig. 32-2-3 Zygote Cleavage Eight-cell stage Cleavage Blastula Cross section of blastula Blastocoel Gastrulation Blastopore Gastrula Archenteron Ectoderm Endoderm Blastocoel Remember this picture? Gastrulation of the blastospore
Fig. 32-3 OTHER EUKARYOTES Choanoflagellates Sponges Other animals Animals Individual choanoflagellate Collar cell (choanocyte) True animals evolved from clusters of single cell flagellates (animal like Protista) You can see how the sponge is really an asymmetrical cluster of nondifferentiated cells.
Animal Behaviors Innate: 1.Instincts- complex pattern of innate behaviors, reflexes, fight or flight, courtships, species recognition (language, song, flashes of pattern/light) 2.Territory- physical space needed for breeding, feeding, and shelter, organisms can expend a lot of energy defending territory some will fight to the death. 3.Migration- instinctive seasonal movement, response to a changing environment, includes hibernation (cold) and estivation (dry and hot)
Behaviors cont’d Learned: Habituation- animal repeats a successful behavior, and does not repeat an unsuccessful behavior, birds learn which moths are poisonous by color and avoid eating them after becoming ill or getting a bad taste. Deer return to the same grazing field when successful. Imprinting – salmon and turtles return to same stream or beach to lay eggs in which they hatched, the environment left an imprint or memory
Adaptations for Defense: Mechanical- physical structures Chemical- stinging sensations, poisons, bad taste, paralysis Camouflage- color or pattern that blend into environment –Disruptive- ex zebra –Cryptic- ex chameleon and squid –Countershading- ex Fish have light belly and dark back