The Basics of Cell Biology

Cell Biology is the study of cells—the basic units of all living organisms. Scientists who work in this field use techniques from many other disciplines, such as biochemistry, genetics, neurobiology, molecular biology, medical microbiology and cytology. This research contributes to our understanding of how organisms work, including the progression and cures of disease.

The most common goal of cell biologists is to determine how a single cell or group of cells behave. This is accomplished by examining the structures and chemical interactions that take place inside of a cell. Some of the most fundamental activities that occur within a cell include DNA replication, protein production and metabolism, cell movement and cellular signaling.

Each cell is enclosed by a membrane, which is based on a layer of fat-based molecules called phospholipids and studded with proteins. These proteins act like gatekeepers, regulating what can enter and leave the cell and recognizing other cells as either friendly or foreign. Membrane proteins also function as communicators, sending and receiving messages between cells and the surrounding environment.

When a cell is at rest, the concentrations of organic molecules within it are relatively high, but when a cell begins to grow or divide, these levels decrease and require additional energy. This energy is produced through the process of metabolism. Metabolism consists of a series of degradative chemical reactions that break down complex molecules into simpler ones, such as carbohydrates, lipids and amino acids, and produces energy in the form of ATP.