Angiosperm Reproduction Essay

1368 Words 6 Pages
Register to read the introduction… Flowers, produce by the sporophyte, function in sexual reproduction
The four floral organs are sepals, petals, stamens, and carpel. Sepals protect the floral bud. Petals help attract pollinators. Stamens bear anthers in which haploid microspores develop into pollen grains containing male gametophytes. Carpel contains ovules (immature seeds) in their swollen bases. Within the ovules, embryos sacs (female’s gametophytes) develop from megaspore.
Pollination which precedes fertilization is the placing of pollen on the stigma of a carpel. After pollination, the pollen tube discharges two sperm into the female gametophytes. Two sperm are needed for double fertilization, a process in which on e sperm fertilized the egg, forming a zygote and eventually an embryo, which other sperm combines with polar nuclei, giving rise to food-storage endosperm.
The seed coat enclosed the embryo along with a food supply stocked in either the endosperm or the cotyledons. Seed dormancy ensures that seed germinate only when conditions for seedling survival are optimal. The breaking dormancy often requires environmental cues, such as temperature or lighting
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How might this influence effort to prevents transgene escape?
A: in such species, engineering the transgene into the chloroplast DNA would not prevent its escape in pollen; such as method requires that cholorplast DNA be found only in the egg. And entirely different method of preventing transgene escape would therefore be needed, such as male sterility, apomixes, or self-pollinating closed flowers.

Hybridization of different varieties and even species of plants is common in nature and has been used by breeders, ancient and modern, to introduce new genes into crops. After two plants are successfully hybridized, plant breeders select those progeny that have the desired traits.
In genetic engineering, genes from unrelated organism are incorporated into plants. Genetically modified (GM) plants have the potential of increasing the quality and quantity of food worldwide and may also become increasingly important as biofuels.
Two important GM crops are golden rice, which provide more vitamin A and Bt maize, which is insect resistant.
There are concerns about the unknow risk of releasing GM organisms into the environment, but the potential benefits of transgenic crops need to be

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