Concept explainers
To determine: Which among the 3 lifecycles (Refer to Fig.13.6 “Three types of sexual lifecycles”, in the textbook) possess “alternation of generation”. Discriminate it with the other 2 lifecycles.
Concept introduction: Many lifecycles have been evolved among the algae (multicellular). The life cycle that is complex includes the alternation of generation. It means there is alternation between the multicellular diploid or the haploid forms. Thus, alternation of generation is applied to only those lifecycles, where the diploid as well as haploid, both stages exists.
Pictorial representation:
Sexual lifecycles of various organisms is represented in Fig.1.
Fig.1 “Three types of sexual lifecycles”
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Modified Mastering Biology with Pearson eText -- Standalone Access Card -- for Campbell Biology
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