Chapter 30 Plant Bio Diversity Plasmodium spp species Plasmodium falciparium bitten by an Anopheles mosquito transfer parasites in saliva severe fever headache 4 6hr long recur every 1 5 days death can occur w in days 250 million years cases 1 milli die deaths can be as 10 of cases results in death most often children 1 5 chilldren deaths historically chloroquine was used selected for resistant malarial parasites indoor spraying of insecticide long lasting insectidal nets Autotrophic plants Photosynthesis for the C E needs selective pressure has enhanced 1st 3 Algae Protists then move from H2O to land What is a plant this process chlorafil a b pigments enhancing energy production Heterotrophic plants venus fly traps a few strictly heterotrophic plants parasites on other plants very complex life cycles all follow alternation of generation possess cell walls rigidity of plants cellulose lignin structural polysaccharids multi cellular eukaryotic have both chloroplasts mitochandria 1 billion years for land plants to appear likely derived from aquatic protists Green algae Chlorophytes uni multi cellular ulva Charophytes Chara skunkweed closed living relative of land plants based on genome analysis Challenges water land being able to get nutrients dehydration getting H2O roots rhizoid retaining H2O chydrophobic waxy coating on leaves stan strorage in roots structure new diseases lots of herbivores less protection to sunlight other atmospheric characters no organic water soil Charophytes MC green algae water challenging Land free floating gravity based environ environ Capturing retaining H2O roots rhizoid hydrophobic waxy coating on leaves stems storage in roots structural stability GRAVITY rigid cell walls incorporating cellulose lignin woody tissue where will C N P come from relationships w N fixing bacteria roots for uptake facing herbivores eating live plant tissue granivores seed eaters plants have toxins 2o cpds secondary compounds thorns spines protective seed coverings grasses grow better faster when faced w herbivory Seasonal change adapt life cycles to periods of dormacy winter and rapid growth spring Nutrient Uptake summer Plant Life cycles alternation of generations common to all plants multi celluar green red brown algae Diploid vs Haploid with respect to chromosome For Humans we each have 46 chromosomes Diploid of chromosomes Diploid 2n n mom n dad each mom parent provides a haploid n of chromosomes 2n embryo nmom egg ndad sperm gametes always have haploids unicelluar Plants have independent haploid diploid life stages so alternation of generation results from Haploid life stage n Dipolid life stage 2n Alternation of Generations Gametophyte haploid n produces egg sperm Mitosis Egg sperm fertilization joining of egg sperm 2n zygote 2n embryo Sporophyte 2n diploid sporangia 2n spore mom cell Meosis O spore cycle back to Gametophyte Earliest land plants Bryophyta mosses liverworts hornworts no internal plumbing no vascularization no way of moving H2O nutrients around require moist wet habitat often associated w aquatic habitats saturated soils grow close to the ground no true leaves leaf like spikes very simple aggregations of cells no true roots hold plant in place have rhizoids absorb H2O sponge H2O is drawn into plant along single long cells Gametophyte dominate life stage n Bryophtes Bryophyta sporophyte present for short period of time produce haploid spores from diploid spore mother cell hornworts sporophte gametophyte gamephyte liverworts sporophyte mutualistic 0 relationship w cyanobacteria get carbon of glucose N fixers atm N2 ammonia increased plant growth Bryophytes Tracheophytes call other plants all have vacularization internal plumbing 420 million years agao cooksonia sp possessed vascularize vascularization plumbing in shoots stems roots leaves xylem large holes in trees moving H2O dissolved minerals upward phlem smaller holes in trees hormones nutrients food moves everywhere once H2O gets to the leaves it can be released through transpiration Transpiration occurs through small leaf openings stomata mouth like openings can be open close release H2O vapor gas exchange releases O2 take up CO2 waxy cuticle prevents water loss Lycophytes club mosses not moss bryophytes rely on moist environments motile mobile sperm swim to egg Tracheophytes vascularized primitive whisk fern rocky habitats Horshtails gametophyte stage common along aqautic habitats fern also horsetails whisk ferns primarily assoc w moist wet habitats soil moisture air moisture still possess mobile sperm require moisture tree ferns gametophytes both male female structure on gametophyte Pteridophytes sporophyte fern Sporangia seed like structure deer terds burst releasing spores haploid gametophyte Green Algae Bryophyta Tracheophyta Lycophytes Peteridophytes simple vascular system Gymosperms e g pine trees seeds Charophyta water land vascularize plumbing Gymosperms conifers naked seeds bristlecone pine very well in low moitsure oldest single organisms on plant 4 000 5 000 years old dry mountain tops Methuselah 4 842 years old oldest single living organism largest redwoods Sequoia tree 3 Cycads tropical environments largest sperm on Earth 3mm 1 3mm long Gnetophyta e g Welwitschia Namib Desert ancient plant Ephedra pharmaceutical application Gingko biloba Gingkophyta extinct in wild Asia maintained as an ornamental male come gametophte is w in female gametophyte Conifers tiny humans in comparison redwoods cypresses cedars firs spruces pine jumpers NO Gynosperms producers flowers fruits adapted to broad range of environment both wet dry no longer reliant on being near moisture needle are leaves surface area lose less H2O tip of needle stomata open close transpiration gas exchange cuticle waxy caoting hold H2O for long periods of time transfer by wind male cone pollen male gametophyte transfer by wind female cone egg ovules female gametophyte Kidney beans seed leaves gather Energy from the Sun enbryo seedlings can survive on carbos starches in endosperm Benefits of seeds loaded w Energy food endosperm jumpstarts growth covering protection from environment animal damage by outer covering enhance fitness increased likelihood of successful germination dormacy can bridge seasons only need to germinate when conditions are right seed increased possibilities for dispersal wind based dispersal structural adaptations that enhance flight wind based dispersal travel by water when hit surface pollinize e g water
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