Most "big" differences separating phyla have to do with embryological features. Why might a genetic change or mutation that occurs in an embryo have a greater impact on the on the organism than one that occurs at a later stage of development?
Thank you for the opportunity to help you with your question!
Changes occurring in embryo alters the genetic make up of an organism . This changes can be passed over and over,creating a population with the same genetic defect ,that codes for same morphological appearance..This distinct genetic alteration between generations creates a distinct phyla.
Genetic change at a lalter age will mostly affect an individual ,and mostly are not as severe as former. They cannot be passed over to the offsprings unless the mutation involves gonadal cells, which is a rare case.
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Aug 12th, 2015
Hello there, how many biology questions do you have?