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 internal and external methods of fertilization
Describe the methods used by animals for development of offspring during gestation
Describe the anatomical adaptions that occurred in animals to facilitate reproduction

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 chapter, you will be able to do the following:

Describe the roles of male and female reproductive hormones
Discuss the interplay of the ovarian and menstrual cycles
Describe the process of menopause

By the end of this section, you will be able to do the following:

Explain fetal development during the three trimesters of gestation
Describe labor and delivery
Compare the efficacy and duration of various types of contraception
Discuss causes of infertility and the therapeutic options available

By the end of this section, you will be able to do the following:

Describe human male and female reproductive anatomies
Discuss the human sexual response
Describe spermatogenesis and oogenesis and discuss their differences and similarities

By the end of this section, you will be able to do the following:

Describe the process of organogenesis
Identify the anatomical axes formed in vertebrates

By the end of this section, you will be able to do the following:

Describe advantages and disadvantages of asexual and sexual reproduction
Discuss asexual reproduction methods
Discuss sexual reproduction methods

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

Biology is designed for multi-semester biology courses for science majors. It is grounded on an evolutionary basis and includes exciting features that highlight careers in the biological sciences and everyday applications of the concepts at hand. To meet the needs of today’s instructors and students, some content has been strategically condensed while maintaining the overall scope and coverage of traditional texts for this course. Instructors can customize the book, adapting it to the approach that works best in their classroom. Biology also includes an innovative art program that incorporates critical thinking and clicker questions to help students understand—and apply—key concepts.

In this video segment from Nature, crabs face numerous obstacles in their migration from their forest home to the Caribbean Sea. [4:09]

In this Dinosaur Train clip Gilbert teaches the kids about the giant prehistoric sea turtle called Archelon. Gilbert reminds the kids that different species behave differently and have unique life cycles. Take this video as an opportunity to learn the differing ways in which animals reproduce. [2:10]

Meiosis is the process by which gametes (eggs and sperm) are made. Gametes have only one set of chromosomes. Therefore, meiosis involves a reduction in the amount of genetic material. Each gamete has only half the chromosomes of the original germ cell. Explore meiosis with a computer model of dragons. Run meiosis, inspect the chromosomes, then choose gametes to fertilize. Predict the results of the dragon offspring and try to make a dragon without legs. Learn why all siblings do not look alike.