Biology 102 Exam 2 Study Guide
Biology 102 Exam 2 Study Guide BY 102
Jacksonville State University
Popular in Introductory Biology II
Popular in Biology
This 6 page Study Guide was uploaded by Kimberly Burke on Friday January 22, 2016. The Study Guide belongs to BY 102 at Jacksonville State University taught by Dr. Cline in Spring 2015. Since its upload, it has received 22 views. For similar materials see Introductory Biology II in Biology at Jacksonville State University.
Reviews for Biology 102 Exam 2 Study Guide
Report this Material
What is Karma?
Karma is the currency of StudySoup.
You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!
Date Created: 01/22/16
Exam 2 – Plants • Setting the stage for plants o Earth’s atmosphere was originally oxygen free o Ultraviolent radiation bombarded the surface o Photosynthetic cells produced oxy & allowed formation of a protective ozone layer § Ozone – 3 Oxy linked together, reject Ultraviolent radiation, mutation rate drops • Invading the land o Cyanobacteria – 1 to spread into & up freshwater streams – go to where nutrients are o Green Algae & fungi – made the journey together, every plant descended from Green Algae • Kingdom Plantae o Nearly all multicelled, vast majority are photoautotrophs (energy from S2from air, minerals dissolved in water) • Seed – reproductive, has embryo & layers covering embryo; peanuts, chestnut, corn o Seed ferns & Gymnosperms were dominant at first • Carboniferous Period – giant Lycophytes & horsetails, sea level rose & fell repeatedly o Remains of swamp forests were repeatedly submerged & compressed § Club mosses grew & died on top of each other o Result: formation of coal • Seed-Bearing Plants o Microspores that give rise to pollen grains o Megaspores inside ovules o More water-conserving than seedless vascular plants • Pollen – sperm bearing mature male gametophyte that develop from microspores o Allow transfer of sperm to egg w/o water – huge step o Can drift on air currents or be carries by pollinators • Ovules – female reproductive structures that become seeds o Consist of: female gametophyte w/ egg cell, nutrient -rich tissue, jacket of cell layers that will form seed coat • Nonvascular Plants – no specialized tissues to transport materials, rely on diffusion to move materials around plant o Diffusion takes time, plants are smaller o Bryophytes – around 19,000 species; 3 groups: liverworts, hornworts, mosses § Small, nonvascular, non-woody; live in wet habitats, flagellated sperm require water to reach eggs § Gametophyte dominates life cycle – has leaf-like, root-like, & stem-like parts § Mosses – ex) Polytrichum • Life cycle – male + female à zygote à sporophyte à meiosis à germinate à male or female • Peat mosses – used in Civil War to pack wounds – ex) Sphagnum o Grow in acidic bogs; important ecosystems of cold & temperate regions o Can be harvested & burned as fuel § Liverwort – ex) Marchantia – reproduce asexually by gemmae • Gametophytes are male or femal e – sexually § Hornwort – leaf-like structures w/ spikes • Vascular plants – majority of plants, have internal tissue that carry water & solutes, larger plants o Vascular Tissues § Xylem – transports water & nutrients from roots to leaves § Phloem – transports photosynthetic products from leaves to roots o 2 groups: seedless & seed-bearing o Seedless Vascular plant – arose during Deviation Era, produces spores but no seeds § Like bryophytes – live in wet, humid places, require water for fertilization § Unlike bryophytes – sporophyte is free living & have vascular tissues § 4 groups: Whisk Ferns, Lycophytes, Horsetails, Ferns § Lycophytes (Lycophyta) – club mosses, ground pine (look like tiny pine trees, Lycopodium) • Strobili – spore bearing structure (Sporophyte 1N) – look like Candelabra • Stigmaria = “roots”, have dimples like gold ball • Lepidodendron = stem, diamond shapes • Lepidostrobus = branches • Lepidophylloides = flowery § Whisk Ferns (Psilophyta) – ex) Psilotum • Sporangium – reproductive structure (Sporophyte) § Horsetails (Sphenophytes) – ex) Equisetum; used to make scrub brushes • Silica in stems = called scouring rushes; hollow in center § Ferns (Pterophyta) – mostly tropical • Most common sporophyte structure o Perennial underground stem (rhizome) o Roots & fronds arise from Rhizo me o Young fronds are coiled into “fiddle heads” o Mature fronds divide into leaflets o Spores form on lower surface of some fronds o Seed-Bearing Vascular plants st § Gymnosperms arose 1 – naked seeds; Seeds don’t form inside ovary • 4 groups: Cycads, Ginkgos, Gnetophytes, Conifers (pine trees) • Cycads- palm-like appearance, only 100 living species, most diverse during age of dinosaurs o Pollen bearing & seed bearing cones on different plant § Dieceous = 2 types – male & female/pollen & seed • Gnetophytes – 3 genera: Gnetum, Welwitschia, Ephedra • Ginkgos – 1 surviving species: Gikgo biloba (maidenhair tree) o Most diverse during age of dinosaurs o Deciduous trees are male or female (Dieceous) o Only tree remaining w/ parallel veins • Conifers – pine, spruces, redwoods o Do very well at high elevations & high latitude (North) o Widest known, largest # of living species o Woody trees or shrubs; most are evergreen – photosynthesize all year o Most produce woody cones & bear seeds exposed on cone scales o Pine Cones – wood scales where megas pores form & develop into female gametophytes § Male cones – where microspores & pollen are produces – not woody o Conifer distribution – reproduce more slowly than angiosperms; at competitive disadvantage § Dominate far North, higher elevations & certain parts of Southern Hemisphere § Angiosperms arose later – flowering plants; Dominant land plants • Ovule & (after fertilization) seeds are enclosed in ovary • 3 main groups: Magnoliids, Monocots, & Eudicots • Double Fertilization - only in Angiosperms o Male gametophyte delivers 2 sperm to an ovule o 1 fertilizes egg; 1nd fertilizes a cell that gives rise to endosperm (3N) • Magnoliids – leathery leaves, beautiful flowers st • Monocot – stem=monkey face; 1 leaf = embryo o Produce vascular tissue & spread randomly in st em o 1 cotyledon (single embryo), usually 3 flower parts, leaves w/ parallel venation o 1 pore/furrow per pollen grain o Ex) corn (Zea mays) & palm tress • Eudicot – roses, apple trees, lilies o Most flowering plants are Eudicots o Organize vascular tissue uniquely – around the edges of stem o 2 cotyledon, 4 or 5 flower parts, leaf veins netlike o 3 pores/furrows per pollen grain • Alternation of Generations – process in plants where haploid & diploid stages of life cycle alternate o Gametophyte (1N) – 1N Gametes o Sporophytes (2N) – 2 sets of chromosomes, spores – 1N via Meiosis • Adaptations to land o Root systems – physical anchors, grab nutrients, place to store energy o Shoot systems – above ground o Vascular tissues – move things around in plant, help shoot growth o Waxy cuticle – tissue of living thing 97% water, land is too dry, cuticles waterproof exposed surfaces to maintain water • Traits of Seed Bearing Plants o Pollen grains – arise from microspores, develop into male gametophytes, can be transported w/o water o Seeds – embryo sporophyte inside nutritive tissues & protective coat § Can withstand hostile conditions § Peanut – shell, papery material, nut, sharp pointy end on nut (embryo sporophyte) • People & Plants o Plant domestication began about 11,000 years ago; about 3,000 s pecies used as food; about 200 are major crops § Wheat, corn, rice, barley = 93% of our food source • Nonfood uses of plants -Lumber, paper, fuel, furniture, rope, thatched roofing, drugs, insecticides (Marigolds & Chrysanthemum) • Plants of Abuse – Tobacco (Nicotiana), Marijuana (Cannabis sativa), Coca leaves (Cocaine), toxic plant alkaloids (Henbane & Belladonna) used as poisons & medicines – Hallucinogens • Leaves o Blade – leaf o Vein – deliver water to plant o Midrib – central vein o Petiole – piece between node & leaf o Node – where leaf comes out of stem o Internode – space between nodes o Epidermis – “skin” o Cuticle - help waterproof exposed surfaces in dry habitats to help maintain water o Stomata – surrounded by 2 guard cells, determine what happens in leaf, lets atmos pheric gasses into leaf, respire (let water out) as plant metabolizes o Spongy Parenchyma/Mesophyll – where photosynthesis happens, allows atmospheric gasses to penetrate plant o Alternate Attachment – leaves grow in alternate places on each side of stem o Opposite Attachment – leaves grow in the same spot on opposite sides o Chordal Attachment - leaves grow in clusters • Roots – absorb material, hold plant in place, store nutritive tissue & energy o Aerial Roots – exposed roots o Fibrous Roots – hold plant in place – sand grasses o Pneumatophores roots – knees live above water t send oxy to cells under water – like a snorkel o Prop Roots – expand base, plant won’t tip over o Tap Roots – deep in soil, store nutrients & energy to rebuild plant, store energy for future growth – kudzu o Tuberous Roots – each root breaks off to make new plants, store energy for future growth – potatoes o Zone of elongation – contributing to growth by increasing length of cells o Root cap – protects root o Root hairs – extension of individual cells, increase surface area of root, absorb water & minerals o Secondary roots – increase surface area, stabilize • Plant Growth o Meristems – actively growing regions o Apical Meristem – where plants are actively growing, where cell division happens, add newof roots & shoots o Lateral Meristem – branches, flowers, & some leaves o Bark – epidermis of tree, all layers produced by LMS • Plant Tissue Types – ground tissue system, vascular tissue, & dermal tissue o Simple tissue – parenchyma, collenchyma, sclerenchyma § Parenchyma Cells – pliable, thin walled, many sided, mature cells (alive, can divide) • Mesophyll of leaves – spot for photosynthesis § Collenchyma Cells – flexible support, thick cell walls, patches of living cells, upright support • Pectin “glues” cellulose tog ether – Polysaccharide (not protein) § Sclerenchyma Cells – lignin impregnated cell walls to add compressive strength • Lignin – resistant to fungus, waterproofing, transport functions, • Fibers – long tapered cells – cloth, paper, ropes • Sclerids – short & stubby, hard seed coats – coconut shell, “grit” in pears, peach pit o Complex Tissue § Vascular tissues – Xylem (transports water) & Phloem (transports photosynthetic material) • Xylem & Phloem = Vascular bundles § Dermal Tissues • Epidermis – 1 cell thick, unspecialized cells – make cuticle • Specialized cells o Stomate – 2 guard cells surrounding an opening § Guard ells – regulate photosynthesis • Dormancy – arrested growth, keeps seed from germinating at inappropriate times o Sacred Lotus – plant in Egypt sent to tomb w/ Pharaohs, grew 2000 years later o Arctic Lupine – produces seeds eaten by Lemmings, 100 year old seeds in burrows § Seeds waited for appropriate conditions to germinate § Climate change – new seeds competing w/ 1000 year old seeds o Breaking Dormancy § Dehydration/Rehydration – dehydrate seed & rehydrate at another time • Swell w/ water by process of imbibition § Cold Shock – ex) Kudzu need cold shock to germinate § Light – require light to grow, certain wavelengths may be required (especially red) • Even when dormant seeds can track daylight/night § Scarification – rough up seed coat so water & light can get to seed • Mechanically, thrown around, or digested (chemically) • Tree on island w/ dodo bird – dodo chemically scarified seed, humans killed dodo § Chemical Inhibition – some plants add metabolic poison to seeds that organisms eat & stop metabolism of organism; Metabolic inhibitors: Arsenic, Cyanide, Strychnine • Apples store Arsenic; Green on Potato chips – strychnine; Cherries have Cyanide • Plant Growth o Pheromones – chemical messengers inside body o Hormones – chemical messengers outside body • Plant Hormones o Gibberellins – synthesized in AMS of bud, leaf, roots, & seed; may travel in xylem & phloem § Make stems lengthen by stimulating cell division & elongation § Often contributes to flowering; helps bud/seed dormancy § Foolish Singling Disease – mutation in rice that makes plants grow too fast & die o Auxins – synthesized mainly in AMS of bud, leaf, & seed; diffuses from cells in 1 direction (away from AMS) § Stimulate apical dominance, tropisms, vascular cambium divisions, vascular tissue development, fruit formation § Inhibit leaf & fruit abscission (falling off) § Apical Dominance – inhibits branching, inhibits lateral growth o Cytokinins – synthesized mainly in root tip, travels from roots to shoot § Stimulates cell division, leaf expansion; Inhibitory effect on leaf aging; release buds from apical dominance o Ethylene (a gas) – synthesized in most parts undergoing ripening, aging, or stress; diffusion in all directions § Stimulates fruit ripening; abscission of leaf, flower, & fruit o Absisic Acid (ABA) – synthesized in mature leaf, in stems, or in unripened fruit in response to water stress § Stimulates stomate closure, development of embryo sporophytes, distribution of photosynt hetic products to seeds, product storage & protein synthesis in seeds § May influence dormancy in some species • Growth Regulators o Brassinoides – steroid – influence cell division, elongation, required for normal growth § Protect against pathogens & stress o Jasmonates – volatile (liquid à gas quickly) compound derived from fatty acid § Influences seed germination, root growth, protein storage, & defense § Stimulate plants to defend themselves – make plant taste bad & warn the next plant o Salicylic Acid – aspirin – influences tissue defense responses to pathogens & injury – defense molecule o Systemin – peptide – synthesized in damaged tissues – influences defense responses in damaged tissues § Builds defense molecules to protect against pathogens o Indoleacetic Acid (IAA) – manufactured by humans – synthetic plant hormone § Stimulates root growth in cuttings § Rootone – stimulates root growth o 2, 4, D – synthetic oxine – herbicide (kills plants) & defoliant § Breaks down into 2, 4, 5 T; 2, 4 D + 2, 4, 5 T = Agent Oran ge – used in Vietnam War • Tropisms – directed growth/movement, use hormones to grow differently based on environmental factors o Gravitropism – growth in response to gravity – § Different roots vs shoots • Roots – detect gravity, respond positively • Shoots – negative gravitropism, know center of gravity & grow away from it § Statolith – heavy starch - float in cytoplasm, accumulate toward the gravity pull, detect gravity to direct growth • Auxins cause the cells on the lower side of stem to grow more rapidly o Phototropism – growth in response to light – can be (+) or (-), tends to be (+) in plant growth § Auxins change growth on 1 side of plant o Thigmotropism – growth or movement in response to touch – § Grapes & muscadines (throw out tendrils) - Grow around whatever they touch § Venus Fly Trap – leaves move to trap insect § Mimosa – touch leaf & leaf wraps itself up – defense o Mechanical Stress – growth in response to physical buffeting § Along coast or high mountains the branches are shorter on the windward side § Ethylene gas may be a player – higher concentration on leeward side o Insect Damage – insect galls, growth in response to insect attack § Insect lay eggs in plant tissue – insect galls • Sexual Reproduction o Benefit – high genetic variability o Cost – need 2 individuals in the right contact at the right time, not energetically cheap, cannot generate a lot of individuals, do not make exact copies of parent • Modes of Sexual Reproduction o Want offspring far from parents, cannot compete w/ parent o Wind Dispersal § “Dust” seeds – orchids § “Parachute” seeds – dandelions § “Helicopter” seeds – maple seeds o Animal Dispersal – “taxi service” – animals pick up & spit out miles from where they picked them up § Seeds stick to people § “free lunch” – animals swallow seeds & disperse them • Asexual Reproduction o Benefits – only need 1 individual, energetically cheap (use tissue you already have), can generate a lot of individuals, make “exact” copies of parent plant (still have a chance of mutation) o Cost – no genetic Variability • Modes of Asexual Reproduction in Flowering Plants o Runner – strawberry – new plants arise at nodes along aboveground horizontal stems o Rhizome – Bermuda Grass – new plants arise at nodes of underground horizontal stems o Corm – Gladiolus – New plants arise from auxiliary buds on short, vertical underground stems o Tuber – Potato – new shoots arise from axillary buds - enlarged tips of slender, underground rhizomes o Bulb – onion, lily, tulips – new bulbs arise from axillary buds on short underground stems o Pathogenesis – orange, rose – embryo develops w/o nuclear or cellular fusions § An unfertilized haploid egg or by developing accidentally from tissue surrounding the embryo sac § Female produces viable, fertile egg w/o male contribution o Vegetative Propagation – jade plant, African violet, quaking aspen - new plant develops from tissue of structure (ex. A leaf) that drops from the parent plant or is separated from it § Plant derives from plant tissue that is separated from parent plant o Tissue Culture Propagation – orchid, lily, wheat, rice, corn, tulip – new plant is induced to arise from a parent plant cell that has not become irreversibly differentiated § Only occurs in the lab, a single cell contains all the necessary DNA, stimulate cell to grow new plant • Parts of a flower o Stamen – male § Pollen – male DNA/sperm § Anther – pollen bearing § Filament -support o Pistil/Carpel – female § Stigma – male pollen sticks to sticky top – rejects self pollen § Style – support – adds depth & length to flower § Ovary – encases ovule § Ovule – where eggs are made • Start w/ megaspore Mother cell (2N), go through Mitotic division • Produces 8 cells – 6 cells w/ 1 set & 2 cells that fuse & have 2 sets of chromosomes • Fused cells – get most of the cytoplasm – endosperm • Any 1 of 3 at the bottom of the cell could be fertilized & become egg cell o Perianth § Petal (corolla) – modified leaves § Sepal (calyx) – modified leaves – protective o Receptacle – where everything attaches o Stem (pedicel) • Plant Life Cycle o Pollen grain attaches from another individual o Chemical reaction occurs o Pollen grain grows & develop a pollen tube that dumps enzymes & digests through style o Pollen tube grows until it reaches micropyle, penetrates micropyle o Sperm nuclei come forward – 1 fertilizes a 1 female cell & 1 fertilizes endosp erm (now 3N) o Zygote & Endosperm are nutritive cells • Fruit Types o Simple Dry Fruits § Dehiscent Fruit – wall w/ definite seams to release seeds (peas, green beans, mustard seeds) § Indehiscent Fruit – wall w/o definite seam (ac orn, grains (corn), sunflower, carr ots, maple) o Simple Fleshy Fruits § Berry – compound or simple ovary, many seeds (tomato, grapes, banana, blueberry) • Pepo – ovary wall w/ hard rind – watermelon & cucumber • Hesperidium – ovary wall w/ leathery rind – oranges, lemons, & grapefruit • Drupe – 1-2 seeds, thick skin, flesh, seed w/in hardened ovarian tissue o Peach, cherry, apricot, almond, olive o Aggregate Fruits – 1 flower, many ovaries, 1 receptacle, many seeds – blackberry & raspberry o Multiple Fruits – combine ovaries of many flowers – pineapple o Accessory Fruits – most tissues not derived from ovary – many derived from receptacle § Pomes – apples, pears; strawberries
Are you sure you want to buy this material for
You're already Subscribed!
Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'