You can measure your aptitude and interest in the work of the biologist by taking courses in the field. Laboratory assignments, for example, provide information on techniques used by the working biologist. Many schools hire students as laboratory assistants to work directly under a teacher and help administer the laboratory sections of courses.

School assemblies, field trips to federal and private laboratories and research centers, and career conferences provide additional insight into career opportunities. Advanced students often are able to attend professional meetings and seminars.

Part-time and summer positions in biology or related areas are particularly helpful. Students with some college courses in biology may find summer positions as laboratory assistants. Graduate students may find work on research projects conducted by their institutions. Beginning college and advanced high school students may find employment as laboratory aides or hospital orderlies or attendants. Despite the menial nature of these positions, they afford a useful insight into careers in biology. High school students often have the opportunity to join volunteer service groups at local hospitals. Student science training programs allow qualified high school students to spend a summer doing research under the supervision of a scientist. If you participate in such a program, take the opportunity to talk to the scientists about their research interests and career paths in biology.

Biology can be divided into many specialties. The biologist, who studies a wide variety of living organisms, has interests that differ from those of the chemist, physicist, and geologist, who are concerned with nonliving matter. Biologists may be identified by their specialties. Following is a breakdown of the many kinds of biologists and their specific fields of study:

Anatomists study animal bodies from basic cell structure to complex tissues and organs. They determine the ability of body parts to regenerate and investigate the possibility of transplanting organs and skin. Their research is applied to human medicine.

Aquatic biologists study animals and plants that live in water and how they are affected by their environmental conditions, such as the salt, acid, and oxygen content of the water and temperature, light, and other factors.

Astrobiologists, also known as exobiologists and space scientists, study the origin of all life forms—from a simple one-celled organism, to plants, to human beings. They study and research the evolution, distribution, and future of these life forms, on Earth as well as on other planets in our solar system and beyond.

Biochemists study the chemical composition of living organisms. They attempt to understand the complex reactions involved in reproduction, growth, metabolism, and heredity.

Biophysicists apply physical principles to biological problems. They study the mechanics, heat, light, radiation, sound, electricity, and energetics of living cells and organisms and do research in the areas of vision, hearing, brain function, nerve conduction, muscle reflex, and damaged cells and tissues.

Biotechnicians, or biological technicians, assist the cornucopia of biological scientists in their endeavors.

Botanists study plant life. Some specialize in plant biochemistry, the structure and function of plant parts, and identification and classification, among other topics.

Cytologists, sometimes called cell biologists, examine the cells of plants and animals, including those cells involved in reproduction. They use microscopes and other instruments to observe the growth and division of cells and to study the influences of physical and chemical factors on both normal and malignant cells.

Ecologists examine such factors as pollutants, rainfall, altitude, temperature, and population size in order to study the distribution and abundance of organisms and their relation to their environment.

Entomologists study insects and their relationship to other life forms.

Geneticists, also known as genetic scientists, study heredity in various forms of life. They are concerned with how biological traits such as color, size, and resistance to disease originate and are transmitted from one generation to another. They also try to develop ways to alter or produce new traits, using chemicals, heat, light, or other means.

Histopathologists investigate diseased tissue in humans and animals.

Immunologists study the manner in which the human body resists disease.

Limnologists study freshwater organisms and their environment.

Marine biologists specialize in the study of marine species and their environment. They gather specimens at different times, taking into account tidal cycles, seasons, and exposure to atmospheric elements, in order to answer questions concerning the overall health of sea organisms and their environment.

Microbiologists study bacteria, viruses, molds, algae, yeasts, and other organisms of microscopic or submicroscopic size. Some microorganisms are useful to humans; they are studied and used in the production of food, such as cheese, bread, and tofu. Other microorganisms have been used to preserve food and tenderize meat. Some microbiologists work with microorganisms that cause disease. They work to diagnose, treat, and prevent disease. Microbiologists have helped prevent typhoid fever, influenza, measles, polio, whooping cough, and smallpox. Today, they work on cures for AIDS, cancer, cystic fibrosis, and Alzheimer's disease, among others.

Molecular biologists apply their research on animal and bacterial systems toward the goal of improving and better understanding human health.

Mycologists study edible, poisonous, and parasitic fungi, such as mushrooms, molds, yeasts, and mildews, to determine which are useful to medicine, agriculture, and industry. Their research has resulted in benefits such as the development of antibiotics, the propagation of mushrooms, and methods of retarding fabric deterioration.

Nematologists study nematodes (roundworms), which are parasitic in animals and plants. Nematodes transmit diseases, attack insects, or attack other nematodes that exist in soil or water. Nematologists investigate and develop methods of controlling these organisms.

Parasitologists study animal parasites and their effects on humans and other animals.

Pharmacologists may be employed as researchers by pharmaceutical companies. They often spend most of their time working in the laboratory, where they study the effects of various drugs and medical compounds on mice or rabbits. Working within controlled environments, pharmacologists precisely note the types, quantities, and timing of medicines administered as a part of their experiments. Periodically, they make blood smears or perform autopsies to study different reactions. They usually work with a team of researchers, headed by one with a doctorate and consisting of several biologists with master's and bachelor's degrees and some laboratory technicians.

Physiologists are biologists who specialize in studying all the life stages of plants or animals. Some specialize in a particular body system or a particular function, such as respiration.

Wildlife biologists study the habitats and the conditions necessary for the survival of birds and other wildlife. Their goal is to find ways to ensure the continuation of healthy wildlife populations, while lessening the impact and growth of civilization around them.

Zoologists study all types of animals to learn their origin, interrelationships, classifications, life histories, habits, diseases, relation to the environment, growth, genetics, and distribution. Zoologists are usually identified by the animals they study: ichthyologists (fish), mammalogists (mammals), ornithologists (birds), and herpetologists (reptiles and amphibians).

Biologists may also work for government agencies concerned with public health. Toxicologists, for example, study the effects of toxic substances on humans, animals, and plants. The data they gather are used in consumer protection and industrial safety programs to reduce the hazards of accidental exposure or ingestion. Public-health microbiologists conduct experiments on water, foods, and the general environment of a community to detect the presence of harmful bacteria so pollution and contagious diseases can be controlled or eliminated.