Skip to main content. This service is more advanced with JavaScript available. Advertisement Hide. Alternation of Generations in Plants and Algae. Peters Susana M. Coelho J. Mark Cock. Reference work entry First Online: 01 April This is a preview of subscription content, log in to check access. Bell G The evolution of the life cycle of brown seaweeds. The dominant generation is haploid and the gametophyte comprises the main plant in Bryophytes.
In tracheophytes, the generation that dominates is diploid and the sporophyte has the main plant. The plants grow larger and live longer in the dominant generation whereas the plants in the non-dominant generations are small and hardly visible.
On the other hand, the dominant generations are seen in the form of ferns, trees, or other plants. The dominant generation in vascular plants is the sporophyte, while in the non-vascular plants is the gametophyte. Alternation of Generations — Life Cycle. The alternation of generations include the following stages:.
The diploid sporophyte has a structure called a sporangium. The sporangium undergoes meiosis and forms haploid spores. The spore develops into a gametophyte which is haploid in nature. The gametophyte has the reproductive organs which undergo mitosis to form haploid gametes.
The gametes fertilize to form a haploid zygote which matures into a mature sporophyte. This cycle keeps repeating. Stages of Alternation of Generations. Following are the two stages of alternation of generations:.
Sporophyte Generation. When two haploid gametes fuse together they form a diploid zygote. The average citizen of three generations ago was probably not aware that he was an extreme individualist. You never know when you are going to stumble upon a jewel in the most out-of-the-way corner. But Lessard's a overbearin' son-of-a-gun all round, and he's always breakin' out in a new place.
Slocum was not educated in a university, and his life has been in by-paths, and out-of-the-way places. New Word List Word List. Save This Word! We could talk until we're blue in the face about this quiz on words for the color "blue," but we think you should take the quiz and find out if you're a whiz at these colorful terms. Origin of alternation of generations First recorded in — Words nearby alternation of generations alternating pulse , alternating series , alternating tremor , alternating voltage , alternation , alternation of generations , alternation of heart , alternative , alternative conjunction , alternative curriculum , alternative energy.
How to use alternation of generations in a sentence Such errors are important because generations of young students now learn American history through film. Will Texas Stay Texan? The Salvaging Of Civilisation H.
Herbert George Wells.
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