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A fruit is the mature, ripened ovary of a flower following double fertilization in an angiosperm.Because gymnosperms do not have an ovary but reproduce through fertilization of unprotected ovules, they produce naked seeds that do not have a surrounding fruit, this meaning that juniper and yew "berries" are not fruits, but modified cones.
Diagram of an ovule in gymnosperms and angiosperms Photomicrograph of an ovule of a monocotyledon. In angiosperms the gynoecium, also called pistil, consists of one or more carpels or carpel leaves that form a cavity, the ovary, inside which the ovules or seminal primordia are protected from both desiccation and attack by phytophagous insects.
Location of ovules inside a Helleborus foetidus flower. In seed plants, the ovule is the structure that gives rise to and contains the female reproductive cells. It consists of three parts: the integument, forming its outer layer, the nucellus (or remnant of the megasporangium), and the female gametophyte (formed from a haploid megaspore) in its center.
The term angiosperm fundamentally changed in meaning in 1827 with Robert Brown, when angiosperm came to mean a seed plant with enclosed ovules. [ 35 ] [ 36 ] In 1851, with Wilhelm Hofmeister 's work on embryo-sacs, Angiosperm came to have its modern meaning of all the flowering plants including Dicotyledons and Monocotyledons.
Close-up of a Schlumbergera flower, showing part of the gynoecium (specifically the stigma and part of the style) and the stamens that surround it. Plant reproductive morphology is the study of the physical form and structure (the morphology) of those parts of plants directly or indirectly concerned with sexual reproduction.
In ferns, gymnosperms, and flowering plants (angiosperms), the gametophytes are relatively small and the sporophyte is much larger. In gymnosperms and flowering plants the megagametophyte is contained within the ovule (that may develop into a seed) and the microgametophyte is contained within a pollen grain.
In flowering plants, the ovule (from Latin ovulum meaning small egg) is a complex structure born inside ovaries. The ovule initially consists of a stalked, integumented megasporangium (also called the nucellus). Typically, one cell in the megasporangium undergoes meiosis resulting in one to four megaspores. These develop into a megagametophyte ...
The female gametophyte, the megagametophyte, that participates in double fertilization in angiosperms which is haploid is called the embryonic sac. This develops within an ovule, enclosed by the ovary at the base of a carpel. Surrounding the megagametophyte are (one or) two integuments, which form an opening called the micropyle.