Copyright © 2007 Dorling Kindersley
The study of life and living things is called biology. Scientists who study biology are known as biologists. The main branches of biology are zoology (the study of animals), botany (the study of plants), and MICROBIOLOGY (the study of tiny organisms).
Biologists study even more specialized branches within zoology, botany, and microbiology. Cell biology, for example, involves studying one of the smallest units of a living thing. Anatomy, on the other hand, looks at the complete structure of organisms. Physiology is the study of how organisms work.
As well as learning about an organism’s structure, biologists discover how an organism reproduces and grows, how it behaves, where it lives, and how it interacts with other organisms. In this way, today’s biologists build up a complete picture of the biology of an organism. At one time, scientists knew little more about living things than what they looked like.
Microorganisms are living things that are too small to be seen with the naked eye. Microbiology is the study of these microorganisms, which include bacteria, viruses, and some fungi.
Some microbiologists are interested in microorganisms that cause diseases in animals and plants. Some specialize in those microorganisms that may be useful for the manufacture of drugs, or food, such as bread. Others study microorganisms that recycle essential nutrients on Earth and in its atmosphere.
Electron microscopes work by passing a beam of tiny particles called electrons through, or across the surface of, a specimen, and onto a screen. This produces a greatly magnified image. Scanning electron microscopes produce a three-dimensional image that can be captured in a photograph called an SEM.