Pearson, as an active contributor to the biology learning community, is pleased to provide free access to the Classic edition of The Biology Place to all educators and their students.
The purpose of the activities is to help you review material you have already studied in class or have read in your text. Some of the material will extend your knowledge beyond your classwork or textbook reading. At the end of each activity, you can assess your progress through a Self-Quiz.
To begin, click on an activity title.
Lab 2 Enzyme Catalysis
Mitosis and Meiosis
Plant Pigments and Photosynthesis
6-I Bacterial Transformation
6-II DNA Electrophoresis
Genetics of Organisms
Population Genetics and Evolution
10-I Cardiovascular Fitness
10-II Heart Rate in Daphnia
Biomembranes I: Membrane Structure and Transport
Biomembranes II: Membrane Dynamics and Communication
Cardiovascular System I: The Beating Heart
Cardiovascular System II: The Vascular Highway
Cell Structure and Function
DNA Structure and Replication
From Gene to Protein: Transcription
From Gene to Protein: Translation (Protein Synthesis)
Plant Structure and Growth
Properties of Biomolecules
Restriction Enzyme Digestion of DNA
The lac Operon in E. coli
Key Concepts I: Mitosis
There are two kinds of cell division in eukaryotes. Mitosis is division involved in development of an adult organism from a single fertilized egg, in growth and repair of tissues, in regeneration of body parts, and in asexual reproduction. In mitosis, the parent cell produces two "daughter cells" that are genetically identical. (The term "daughter cell" is conventional, but does not indicate the sex of the offspring cell.) Mitosis can occur in both diploid (2n) and haploid (n) cells; a diploid cell is shown below.
In meiosis, diploid parent cells divide and produce the gametes or spores that give rise to new individuals. The parent cell produces four haploid daughter cells.
Prior to both mitosis and meiosis, the chromosomes in the nucleus are replicated. The nucleus then divides. Nuclear division is usually followed by division of the cytoplasm. In mitosis, there is one such division. Meiosis consists of two divisions; since the chromosomes have replicated only once, the four daughter cells have half as many chromosomes as the parent cell.
Let's look more closely at each process, beginning with the cell cycle.