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Plant embryonic development, also plant embryogenesis, is a process that occurs after the fertilization of an ovule to produce a fully developed plant embryo.This is a pertinent stage in the plant life cycle that is followed by dormancy and germination. [1]
The endosperm is a tissue produced inside the seeds of most of the flowering plants following double fertilization. It is triploid (meaning three chromosome sets per nucleus) in most species, [1] which may be auxin-driven. [2] It surrounds the embryo and provides nutrition in the form of starch, though it can also contain oils and protein. This ...
In flowering plants the megasporangium is also called the nucellus, and the female gametophyte is sometimes called the embryo sac or embryonic sac. Developmental processes [ edit ]
Other seed components include the endosperm, which is tissue rich in nutrients that will help support the growing plant embryo, and the seed coat, which is a protective outer covering. The first cell division of a zygote is asymmetric, resulting in an embryo with one small cell (the apical cell) and one large cell (the basal cell). [22]
In Angiosperms, the successful development of the embryo depends on the normal functioning of its endosperm. [ 26 ] The failure of endosperm development and its subsequent abortion has been observed in many interploidal crosses (that is, those between populations with a particular degree of intra or interspecific ploidy ), [ 26 ] [ 27 ] [ 28 ...
Drawing of the head of a four-week-old human embryo. From Gray's Anatomy. Embryo drawing is the illustration of embryos in their developmental sequence. In plants and animals, an embryo develops from a zygote, the single cell that results when an egg and sperm fuse during fertilization. In animals, the zygote divides repeatedly to form a ball ...
Therefore, maternal contribution to the genetic constitution of the triploid endosperm is double that of the embryo. One primitive species of flowering plant, Nuphar polysepala, has endosperm that is diploid, resulting from the fusion of a sperm with one, rather than two, maternal nuclei. It is believed that early in the development of ...
In embryology, Carnegie stages are a standardized system of 23 stages used to provide a unified developmental chronology of the vertebrate embryo.. The stages are delineated through the development of structures, not by size or the number of days of development, and so the chronology can vary between species, and to a certain extent between embryos.