Cells

Cells

After studying this chapter, readers should be able to

1. Explain the parts of a cell’s structure.

2. Describe the structure and function of the cell membrane.

3. Describe the structure and function of cytoplasm and cytosol.

4. Describe the parts of the cell nucleus and their functions.

5. Describe the “powerhouses” of the cell.

6. Describe the processes that transport substances across the plasma membrane.

7. Compare and define cilia and flagella.

8. Compare passive and active cell mechanisms.

9. Describe gene activation in protein synthesis.

10. Explain cell division and cancer.

Overview

Cells are the building blocks of all plants and ani-mals. All cells come from the division of preexisting cells. They are the smallest units of the body that per-form all vital physiological functions. Approximately, 75 trillion cells exist in an adult human being. Each cell maintains homeostasis at the cellular level. Cells have different sizes, shapes, and forms, depending on their functions. Today, the study of cellular structure and function or cytology is part of the broader disci-pline of cell biology, which includes aspects of biology, chemistry, and physics.