The stamen of a flower consists of a thin

The stamen of a flower consists of a thin - zygote becomes...

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The stamen of a flower consists of a thin, stemlike filament and an anther, where haploid pollen  grains are produced. Each pollen grain is a male gametophyte containing sperm cells. The pistil  consists of a sticky  stigma;  a  style , which is a narrow stalk connecting the stigma to the top of the  ovary; and the ovary, which is where the ovules are enclosed. In each ovule, a single mother cell  divides to produce four cells, one of which will develop into a female gametophyte. The female  gametophyte is a sac in which there are eight cells, one of which is the egg cell. The ovary becomes  the seed when its egg has been fertilized.  In the angiosperm life cycle, a pollen grain lands on the stigma and produces a pollen tube that  grows from the pollen grain down through the style, penetrating the ovary to reach the ovule. One of  the sperm cells in the pollen tube fertilizes the egg cell in the ovary to produce a diploid zygote. The 
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Unformatted text preview: zygote becomes the new plant embryo. Another sperm cell fuses with two other cells in the female gametophyte to produce a triploid (three sets of chromosomes) endosperm nucleus, which develops into the endosperm that will feed the growing embryo. The ovule becomes the seed in which the embryo develops, and the ovary ripens into a fruit. During plant development, the cells become more specialized. In angiosperms, the embryo remains dormant for a while. When the seed germinates, the embryo grows further. Germination may depend on the availability of oxygen, a suitable temperature, or adequate light. Germination requires the availability of stored food within the seed. In plants called monocots (monocotyledon plants), most of the food is stored in the endosperm, in one seed leaf called a cotyledon...
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