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47 Cards in this Set
- Front
- Back
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evolution of plants
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-most likely from water based green algae
-first two plants to appear were mosses and liver worts -adaptation occured slowly to moist areas and were in small size |
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Gymnosperm
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-coniferous
-"naked seed" -seeds have no coat -seeds are on scales of cones -thrive in long cold winters -->harsh conditions important for economy (ie. forestry, pulp and paper etc) |
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Angiosperm
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-flowering plants
-more diverse in structure and location than gymnosperms -important for food sources -furthered classified into monocots and dicots |
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Plant classification
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Plants
Vascular + Non vascular ↓ seeded + seedless ↓ Angiosperm + Gymnosperm ↓ monocots + dicots |
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adaptations for algae
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-KINGDOM PROTISTA
-photosynthetic -cant prevent water loss, so must live in aquatic environments -no waxy cuticle BENEFITS: -provide air to breathe -base of aquatic food chain -serve as shelters -> kelp form underwater forests |
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similarities of plants and algae that prove they have evolved from them
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-both have same photosynthetic pigments (chlorophyll a&b, carotenes etc.)
-both use starch to store photosyntheitc products -both have cellulose in their wall -both have alternation of generation -both form a cell plate during cell division |
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brytophytes
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-no vascular tissue
-moss -absorbs water through their surface -two life stages sporophyte and gametophyte -alternation of generation |
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adaptations of brytophytes
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DISADVANTAGE:
-if environment dries up so does moss -cannot grow very tall limited to moist environment |
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alternation of generation
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when same individual switches between 2 body forms
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Sporophyte
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-diploid (2n)
-reduced generation of all mosses -has no chloroplasts, lives parasitically off of the gametophyte -produces spores through meiosis -spores can develop without fertilization -responsible for distribution of moss species -Meiosis creates haploid spores that grow into the gametophyte |
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Gametophyte
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-haploid (n)
-creates male and female gametes(that can combine to make the sporophyte -dominant generation of all mosses -green leafy structures -responsible for sexual reproducion |
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Moss life cycle
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1.female gametophyte releasess an egg fro her archegonium
2.male gametophyte have sperms in their anthheridia 3. in spring, raindrops splash sperm from male to female gametophytes 4. the fertilized egg (zygote) begins the sporophyte generation 5. sporophyte matures and releases spores 6. spores land on the gorund and start growing into the next gametophyte generation |
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ecological significance
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-reduces erosion along streams
-is responsible for water and nutrient cycling in forests -insulates the arctic permafrost |
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purpose of phloem
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-transports food dissolved in water from one plant to another (translocation)
two way flow |
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Structure of phloem
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-made up of NO LIVING NUCLEI
-have sieve tube element, companion cell, sieve plate 1. sieve tubes are hollow and have sieve plates at each end 2.sieve plates are perforated to allow water to pass through (working against gravity, theory is in a "lock way") 3. Companion cells are connected to sieve tubes and control their funtion |
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Translocation
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-carried out by the phloem
-glucose produced by leaves is temporarily stored in the leaves as starch -starch must be broken down into sucrose for transportation |
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Transport in Phloem
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most widely accepted theory is the mass flow theory
- relies on combo of osmosis and pressure dynamics 1. high concentration sugar displaces water and moves to low concentration 2. high concentration has higher pressure therefore displaces 3. cycle repeats |
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two types of vascular tissue
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phloem and xylem
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purpose of xylem
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-transports water and dissolved minerals
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structure of xylem
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made up of two types of xylem cells: tracheids and vessel elements
-both are non-livingn cell walls of previously living cells -pits along sides all water to move laterally -tracheids found in angiosperms and gymnosperms -vessel elements |
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3 theories of transport in xylem
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root pressure, capillary action, transpiration pull
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Root pressure
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-pressure built up in roots which forces water and dissolved minerals upward
-water is moved into xylem of roots in 2 possible ways: a.cells actively pumping/secreting water into xylem tssue b.cells actively transporting minerals into xylem |
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Capillary action
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-relies on adhesive properties of water
-involves the binding/adhesion of water molecules to xylem tube alls, allowing it to climb upwards |
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Transpiration pull
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-most widely accepted explantion
-relies on evaporation of water form leaves to pull water upwards from the roots |
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mineral transport
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-minerals taken up by roots through active transport
-Ions pass through layer of cells and are released into xylem tissue -move with water throughout the plant -minerals must be dissolved in water to be taken up by plant |
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Monocots vs Dicots
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MONOCOTS
-1 cotyledon -usually 3 floral parts (petals)/multiples of 3 -parallel array of leaf veins -one pore/furrow in pollen grain -vascular bundles are scattered DICOTS -2 cotyledon -4-5 floral parts/petals -netlike array of leaf veins -3pores/furrows in pollen grain -vascular bundles are arranged in a ring around the stem |
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Vascular tissue
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-tubes to transport water and dissolved food in a plant
-vascular bundles are continuous from root to stem to leaf |
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Monoecious plants
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have separate male and female flowers on the same plant.
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Dioecious plants
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have male flowers on one plant,
and female flowers on another plant |
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function of roots
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-anchors the plant
-prevents soil erosion -storage of nutrients (starch) -involved in nutrient movement -->absorbs water and regulates minerals |
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root types
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1.fibrous root = large amt of small roots, not deep
2. tap roots = primary root only, sometimes small horizontal roots develop primary root=root that develops form seed seondary root = small roots that come off primary rot |
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Gas exchange in roots
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-root hairs are responsible
-root hairs allow for increase in surface area -moist surface for gas exchange |
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leaf functions
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-absorbing suns rays
-majority of photosynthetic production (any green part of plant) -taking CO2 and releasing O2 and water vapour -removing waste -using osmotic pressure to draw water up |
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Parts of leaf
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-epidermis =outer layer
-cuticles -stomata (stroma) -palisade mesophyll -spongy meophyll -vascular bundles |
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Stroma
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controls gas exchange between leaf and environment
- has two guard cells that border each stomata -open during day ad closd at night to open: -water flos into guard cells -increase water pressure -guard cell membrane pushes out to close: -water flows out guard cells -decrease in water pressure -guard cell membrane closes |
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Palisade meosphyll
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-consists of parenchyma cellls
-has chloroplasts |
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Spongy mesophyll
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-air space allowing free gas low
-transpiration happens here |
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equation of photosynthesis
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6CO2+6H20--> 6O2+C6H1206
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Autotroph
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-primary producer
-organism that creates its own energy/food form the sun |
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Heterotroph
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-consumer
-organism that eats other organisms to get energy |
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Which step in food chain would have most biomass?
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biomass=mass of livivng material
- primary producers |
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Food web
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illustrate the complex interaction of organisms in the various pyramid
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energy pyramid
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show the biomass or biomass productivity at each trophic level in a given ecosystem.
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Why are there rarely more than 5 trophic levels in any food chain?
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- Not enough energy to go through many trophic levels
- Only the energy used for growth can be passed to the next level… the rest of the energy from food is used up with bodily processes and lost as waste |
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Percentage of energy transferred from one trophic level to the next
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10%
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energy relationships at trophic levels
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- Energy transfer → largest amounts of energy stored is located at lower levels of trophic structure
- Secondary productivity → conversion of energy of food eaten into biomass within the consumer |
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Food chain
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shows specific energy transfer between specific organisms in an ecosystem
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