Which tracheophyte lineage bears exposed ovules on the surface of modified megasporophylls______________?
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Answer: C. Gymnosperms
Explanation
Gymnosperms are seed-producing plants characterized by having unprotected or exposed ovules on sporophylls. The term gymnosperm literally translates from Greek to mean naked seeds in botanical classification. These reproductive structures lack the protective ovary coverings found in flowering plant species. Gymnosperms include familiar conifer trees such as pines, firs, spruces, and ancient cycads. Wind pollination is commonly utilized by gymnosperms to transfer pollen grains to exposed female ovules. Seeds develop directly on the surfaces of scales forming cones rather than enclosed inside fruits.
Gymnosperms dominate vast boreal forest ecosystems across northern temperate regions of the planet. Timber and paper industries rely heavily on the commercial harvest of gymnosperm tree species. Their evolutionary adaptation of seeds allowed plants to reproduce successfully away from watery environments. Spheospsida refers to horsetails and related fern allies that reproduce via spores rather than seeds. Filicineae encompasses true ferns which reproduce using spores and completely lack true seed structures. Angiosperms produce enclosed seeds hidden securely within flowers and true fleshy or dry fruits.
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