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Answers:Gymnosperms are a taxonomic class that includes plants whose seeds are not enclosed in an ovule (like a pine cone). Gymnosperm means as "naked seed". This group is often referred to as softwoods. Gymnosperms usually have needles that stay green throughout the year. Examples are pines, cedars, spruces and firs. Some gymnosperms do drop their leaves - ginkgo, dawn redwood, and baldcypress, to name a few.
Answers:You need points of similarity and difference between these two and the other plant classes. The gymnosperms and angiosperms are classed as tracheophytes (vascular plants) but so are ferns and plants with minimal vascularization like lycopods (club & spike mosses.) The gymnosperms and angiosperms are further classified together omitting the ferns and lycopods, as seed bearing plants with pollen. Gymnosperm seeds differ in several ways from angiosperm seeds. The absence of an ovary and the endosperm (the food stored for the seed to grow from until photosynthesis begins) is -haploid- since it is grown from the female gametophyte *before pollination* in gymnosperm species. Cones are single sexed. Male cones release pollen to female cones that bear exposed seeds under the scales of the cone. Pollination is by wind. http://hcs.osu.edu/hcs300/gymno.htm Angiosperms have diploid seeds with -triploid- endosperm produced in a double fertilization. The embryo and its endosperm in the seed are derived from individual fertilization events in a double fertilization so endosperm is produced *after pollination* in angiosperms. Flowers can be single sexed (either male or female) or have both sexes as when flowers have both stamen and a pistil. Flowers with the female anatomy (pistils) contain the ovary that shelters the seed until mature. Pollination syndrome drives co-evolution of floral form and insect morphology. The mature ovary forms a fruiting body that can be a fleshy fruit or a dry pod of various forms. Cotyledons (seed leaves) also differ between angiosperm and gymnosperm. http://en.wikipedia.org/wiki/Cotyledon
Answers:http://faculty.clintoncc.suny.edu/faculty/Michael.Gregory/files/Bio%20102/Bio%20102%20lectures/Seed%20Plants/seed_plant_life_cycle.gif The SPOROPHYTE is what the GAMETOPHYTE develops in. The GAMETOPHYTE can either be a male structure (MICROSPORANGIUM) or female (MEGASPORANGIUM). The pollen (sperm coated with sporopollenin) travels down the pollen tube (pollenization)to the ovary to get to the OVULE (then fertilization occurs) which develops into SEEDS. The protective coating on the SEED is the INTEGUMENT. I studied this way a while ago by yelling anytime any one of those terms came up in the paragraph. hope that helps.
Answers:Adventitious roots are also found in Gymnosperms and Angiosperms . A root or true root or tap root is the one that develops from the embryonic root primordia , such as a radicle in bean seed . Adventitious roots ( Literally speaking additional roots) develop from ANY OTHER part of a plant . Now click on the link below to see a developing fern plant . " A " is the new sporophyte and " B " is the prothallus . The black worm like part that is moving away from the main body is the true root of fern . Sadly enough it will not function for long and its position will be taken up by adventitious roots that will be developing later on . Root like, but minute threads that you see are the rhizoids of the prothallus ( Do not confuse them with advetitious roots ) Now click the link == http://web.gccaz.edu/~lsola/NonFlwr/thalspo.jpg Another link = http://www.biologie.uni-hamburg.de/b-online/library/webb/BOT311/FERNS/FernSporoGameto400.jpg http://www.bargainmicroscopes.com/images/specimennew/005aab01-005abc4xx-fern-prothallia-sporangia-w.m.jpg Thank you !