Plants1 - epicotyl and hypocotyl. Vegetative Propagation...

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Plants: Essential Processes Gymnosperm Fertilization The female gametophyte contains several archegonia, where the egg cells originate and develop. The gametophyte itself is surrounded by layers of sporangia and integument; all of these elements comprise an ovule, which is found on the surface of a female cone. Fertilization occurs when pollen grains (male gametophytes) are carried by the wind to the open end of an ovule, which contains the eggs, or female gametophyte. There, the pollen grain develops an outgrowth called a pollen tube, which eventually penetrates to the egg cell within one of the archegonia. The sperm cells within the pollen tube then vie to fertilize the egg. Once fertilization has occurred, the embryo develops within the female gametophyte, and the ovule becomes the seed, complete with a food source (the gametophyte tissue) and a seed coat (the integument). This embryo, which will eventually become a new sporophyte, consists of two embryonic leaves, the
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Unformatted text preview: epicotyl and hypocotyl. Vegetative Propagation Through asexual reproduction, many plants can produce genetically identical offshoots (clones) of themselves, which then develop into independent plants. This process is called vegetative propagation, or vegetative reproduction. One way in which vegetative propagation occurs is through fragmentation, a process in which a severed plant part can grow into a whole new plant. Other modes of vegetative propagation include the production of specialized structures such as tubers, runners, and bulbs. The advantages to this kind of asexual reproduction, which can occur either naturally or artificially, stem from the fact that it can occur more rapidly than seed propagation and can allow a genetically superior plant to produce unlimited copies of itself without variation....
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