Angiosperm Phylogeny

Angiosperm Phylogeny , stamens (FLOWER) vessels in xylem Reproductive morphology Hypericum sp. Reproductive morphology: flower Flower parts Flower parts (cont.) Pedicel – stalk of a single flower (from Latin: ped=foot); Receptacle - end of stem on which flower is borne; Sepals - outer (lower) whorl of parts; often greenish; -often function to protect in bud, but sometimes more colorful and showy than petals and attract pollinators; Calyx - collective term for sepals of one flower (from Greek: kalux to cover); Petals - second whorl of parts; often colorful and showy -often function to attract pollinators; Corolla - collective term for petals of one flower (Latin = crown); Perianth – collective term for calyx and petals; Tepals -perianth parts that are not differentiated into sepals and petals (e.g., Tulip) tepals sepal petal Corolla Polypetalous - Gamopetalous/sympetalous - Actinomorphic/radially symmetric/ Zygomorphic/bilaterally regular symmetric/irregular - Flower parts (cont.) Note: in this flower, the pistil is compound, consisting of five fused carpels. (5 fused carpels) Flower parts (cont.) Ovule - Placenta (plural placentae) - ovule Flower parts (cont.) Stamens - pollen bearing part of the flower, consist of long filament (stalk) supporting the anther, where pollen is produced; - provide ‘male’ function in reproduction; Androecium - collective term for ‘male’ portion of flower (G. andro=male, oecium from oikos=house); Carpel - ovule producing structures, consists of swollen ovary at base, elongate style supporting the stigma at the tip, where pollen is deposited and germinates. Style is the structure via which pollen travels down to ovules. -provides ‘female’ function in reproduction; Flowers may have a single carpel or many carpels; the carpels may be separate or fused together Pistil - generalized term for each individual female structure in a flower; When single or separate, each carpel equals one pistil – simple pistil When fused together, one pistil may consist of many carpels - compound pistil Gynoecium - collective term for ‘female’ portion of flower (may be one or many pistils) Carpel vs. Pistil Ovary position Ovary position Superior ovary: ovary arising above the point of insertions of the other flower parts (i.e., perianth parts and stamens); The flowers thus hypogynous, With perianth parts and stamens arising from below the ovary. Inferior ovary: ovary that is beneath the point of insertions of the other floral parts; The flowers epigynous, with perianth and stamens apparently borne upon the ovary. Hypanthium: Flat, cuplike, or tubular structure on which the sepals, petals, and stamens are borne; usually formed from the fused bases of the perianth parts and stamens or from a modified receptacle; Half inferior ovary: A floral condition where the floral parts attach midway on the ovary such that it is partly superior and partly inferior. In this case, the flowers are perigynous, with perianth parts and stamens borne on an hypanthium that surrounds, but is not fused to, the ovary Ovary position quiz hypanthium hypanthium More on flower parts In many flowers the parts in each whorl or the whorls themselves may be fused together. connate - adnate - Connate: gamopetalous corolla Adnate: epipetalous stamens More on flowers complete - incomplete - perfect - imperfect - monoecious - dioecious - polygamous - Imperfect and incomplete Imperfect and incomplete Inflorescence Inflorescence: Inflorescence (cont.) Inflorescence (cont.) Inflorescence (cont.) Inflorescence examples Solitary: a single flower formed in the axil of a leaf (solitary axillary flower) or at the terminus of a vegetative axis (solitary terminal flower). Catkin: inflorescence consisting of a dense, elongated mass of inconspicuous, usually wind-pollinated flowers; also called an ament. Inflorescence examples (cont.) Cyme: determinate, compound inflorescence composed of repeating units of a pedicel bearing a terminal flower and below it, one or two bracteoles; each bracteole is associated with an axillary flower, and further bracteoles, and so on. Corymb: raceme with the pedicels of the lowermost flowers elongated, bringing all flowers to more or less the same level, i.e., a flat-topped raceme. Fruit Fruit: Dehiscent: Indehiscent: Fruit Follicle: a dry, dehiscent fruit derived from a single carpel, opening along one line of dehiscence. Samara: a dry, indehiscent, usually one-seeded, winged fruit Fruit Capsule: a dry, dehiscent fruit derived from two or more united carpels (compound pistil). Drupe: a fleshy fruit usually having a single hard stone that encloses a seed, such as a peach, plum, or cherry. Also called stone fruit. Phylogeny of angiosperms ! Angiosperm! “Basal angiosperm”! ! ! ! ! ! ! AmborellaNymphaealesAustrobaileyalesMagnoliidss Monocots Eudicots Parallel venation! scattered vascular bundles! 1 cotyledon! Tricolpate pollen! After Jansen et al., 2007, Proc. Natl. Acad. Sci. USA 104: 19369-19374! Angiosperm classification Angiosperm classification Phylogeny of angiosperms ! Angiosperm! “Basal angiosperm”! ! ! ! ! ! ! AmborellaNymphaealesAustrobaileyalesMagnoliidss Monocots Eudicots Parallel venation! scattered vascular bundles! 1 cotyledon! Tricolpate pollen! After Jansen et al., 2007, Proc. Natl. Acad. Sci. USA 104: 19369-19374! monocots dicots # of cotyledons stem habit leaves venation flower parts pollen Pinus aristata - bristlecone pine Pinus edulis - pinyon pine Pinus monophylla - singleleaf pinyon pine Pinus contorta - lodgepole pine Pinus banksiana - jack pine Pinus virginiana - Virginia pine.

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