nucellus
Quick Summary
The nucellus is a key part of a plant's ovule, specifically in angiosperms (flowering plants). It is the central tissue within the ovule that encloses the female gametophyte, also known as the embryo sac. The ovule itself is the structure that, after fertilization, develops into a seed.12345
The nucellus plays a role in the development of the embryo sac, which contains the egg cell. After pollination, a pollen tube grows towards the ovule, delivering sperm cells. One sperm fertilizes the egg, forming a zygote that develops into the embryo. Another sperm fuses with polar nuclei to form the endosperm, which serves as food storage for the developing seed. In many angiosperms, the embryo sac enlarges during development, consuming most of the nucellus.341
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angiospermOvulesThis megasporangium is called the nucellus in angiosperms. After initiation of the carpel wall, one or two integuments arise near the base of the ovule primordium, grow in a rimlike fashion, and enclose the nucellus, leaving only a small opening called the micropyle at the top. In angiosperms the presence…
Read MoreThis megasporangium is called the nucellus in angiosperms. After initiation of the carpel wall, one or two integuments arise near the base of the ovule primordium, grow in a rimlike fashion, and enclose the nucellus, leaving only a small opening called the micropyle at the top. In angiosperms the presence…
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plant developmentNutritional dependence of the embryo…within the tissues of the nucellus and acquires abundant food reserves. The proembryo forms after a period of free-nuclear division in the zygote, and the tier of cells above the basal four then elongates to form a suspensor, which pushes the embryonic group deep into the gametophyte. Secondary suspensor cells…
Read More…within the tissues of the nucellus and acquires abundant food reserves. The proembryo forms after a period of free-nuclear division in the zygote, and the tier of cells above the basal four then elongates to form a suspensor, which pushes the embryonic group deep into the gametophyte. Secondary suspensor cells…
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