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http://www.bls.gov/oco/ocos047.htm#training Education and training. A Ph.D. is usually necessary for independent research, particularly in academia, as well as for advancement to administrative positions. A bachelor’s or master's degree is sufficient for some jobs in applied research, product development, management, or inspection; it also may be sufficient to work as a research technician or a teacher. Many with a bachelor's degree in biology enter medical, dental, veterinary, or other health profession schools, or find jobs as high school science teachers. (See the statement on teachers—kindergarten, elementary, middle, and secondary.)
In addition to required courses in chemistry and biology, undergraduate biological science majors usually study allied disciplines such as mathematics, physics, engineering, and computer science. Computer courses are beneficial for modeling and simulating biological processes, operating some laboratory equipment, and performing research in the emerging field of bioinformatics. Those interested in studying the environment also should take courses in environmental studies and become familiar with applicable legislation and regulations.
Most colleges and universities offer bachelor's degrees in biological science, and many offer advanced degrees. Advanced degree programs often emphasize a subfield, such as microbiology or botany, but not all universities offer curricula in all subfields. Larger universities frequently have separate departments specializing in different areas of biological science. For example, a program in botany might cover agronomy, horticulture, or plant pathology. Advanced degree programs typically include classroom and fieldwork, laboratory research, and a thesis or dissertation. A master’s degree generally takes 2 years, and a doctoral degree 5-6 years of full-time study.
Biological scientists with a Ph.D. often take temporary postdoctoral positions that provide specialized research experience. Postdoctoral positions may offer the opportunity to publish research findings. A solid record of published research is essential in obtaining a permanent position performing basic research, especially for those seeking a permanent college or university faculty position.
Aquatic biologists study micro-organisms, plants, and animals living in water. Marine biologists study salt water organisms, and limnologists study fresh water organisms. Much of the work of marine biology centers on molecular biology, the study of the biochemical processes that take place inside living cells. Marine biologists are sometimes called oceanographers, a broader field that also includes the study of the physical characteristics of oceans and the ocean floor. (See the Handbook statement on geoscientists and hydrologists.)