This slideshow helps you discover the beginning of embryonic development and how it is fertilized, how it grows, and how it, in turn, becomes a pregnancy. [2:18]
Find out how cytoplasmic factors in a developing embryo play a vital role in determining which genes to turn on and off for appropriate cell development. [0:56]
See how the three germ layers in early embryonic development eventually lead to the formation of major human organs. [1:29]
Biology 2e is designed to cover the scope and sequence requirements of a typical two-semester biology course for science majors. The text provides comprehensive coverage of foundational research and core biology concepts through an evolutionary lens. Biology includes rich features that engage students in scientific inquiry, highlight careers in the biological sciences, and offer everyday applications. The book also includes various types of practice and homework questions that help students understand—and apply—key concepts. The 2nd edition has been revised to incorporate clearer, more current, and more dynamic explanations, while maintaining the same organization as the first edition. Art and illustrations have been substantially improved, and the textbook features additional assessments and related resources.
By the end of this section, you will be able to do the following:
Discuss how fertilization occurs
Explain how the embryo forms from the zygote
Discuss the role of cleavage and gastrulation in animal development
By the end of this section, you will be able to do the following:
List the features that distinguish the kingdom Animalia from other kingdoms
Explain the processes of animal reproduction and embryonic development
Describe the roles that Hox genes play in development
In this video segment from The Secret of Life school video, "Sex and the Single Gene" follow as a single fertilized egg cell divides, differentiates, and assembles into the tissues and organs of a new organism. [1:20]
This time-lapse microphotography of developing embryos shows the common ancestry of all vertebrates. Footage from NOVA: "Odyssey of Life." [4:42]
Did you know that only a hen (a female chicken) can lay an egg? Eggs need certain things for an embryonic chick to develop and hatch. This unit will help you to understand how a chicken changes from one stage to another as it completes its life cycle. At the end of this lesson you will be able to: Put the stages of a chick’s development in the right order. Label the stages in a chicken's life cycle from a hatched chick to a hen. Explain how hens lay eggs.
