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:

Describe the scientific reasons for the success of Mendel’s experimental work
Describe the expected outcomes of monohybrid crosses involving dominant and recessive alleles
Apply the sum and product rules to calculate probabilities

Students randomly select jelly beans (or other candy) that represent genes for several human traits such as tongue-rolling ability and eye color. Then, working in pairs (preferably of mixed gender), students randomly choose new pairs of jelly beans from those corresponding to their own genotypes. The new pairs are placed on toothpicks to represent the chromosomes of the couple's offspring. Finally, students compare genotypes and phenotypes of parents and offspring for all the "couples" in the class. In particular, they look to see if there are cases where parents and offspring share the exact same genotype and/or phenotype, and consider how the results would differ if they repeated the simulation using more than four traits.

This resource explains Mendel's first law (Law of Segregation) in detail. Includes Mendel's original experiments with results and conclusions.

In a class discussion format, the teacher presents background information about basic human genetics. The number of chromosomes in both body cells and egg and sperm cells is covered, as well as the concept of dominant and recessive alleles. Students determine whether or not they possess the dominant allele for the tongue-rolling gene as an example.