The activity of RNA polymerase II is inhibited by Actinomycin D. When actinomycin D is present, early development in many vertebrate species, for example frogs, can begin after the formation of a blastula (hollow ball of cells that forms after early cleavage divisions), but development stops before gastrulation. Question asked to discuss the activity of maternal gene in contrast to activity of zygotic gene in early frog development. Introduction: Drosophila is the model organism of study of development. It is a well studied genome sequence. Multiple genes are involved in the development of drosophila. The gene that directs the development and fate of an organism are known as developmental genes. Bicoid and Nanos are maternal effect genes; the egg receives these from the mother. Bicoid and Nanos play an important role in creating the anterior to posterior axis. The genes are activated in the fertilized egg (Zygote). In contrast to maternal effect genes, these genes are transcribed by zygotic DNA.

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Chapter 18, Problem 9P

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The activity of RNA polymerase II is inhibited by Actinomycin D. When actinomycin D is present, early development in many vertebrate species, for example frogs, can begin after the formation of a blastula (hollow ball of cells that forms after early cleavage divisions), but development stops before gastrulation. Question asked to discuss the activity of maternal gene in contrast to activity of zygotic gene in early frog development.

Introduction:

Drosophila is the model organism of study of development. It is a well studied genome sequence. Multiple genes are involved in the development of drosophila. The gene that directs the development and fate of an organism are known as developmental genes. Bicoid and Nanos are maternal effect genes; the egg receives these from the mother. Bicoid and Nanos play an important role in creating the anterior to posterior axis. The genes are activated in the fertilized egg (Zygote). In contrast to maternal effect genes, these genes are transcribed by zygotic DNA.

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