Who are the most important people in biology?

If you are asking for important Biologists, some famous ones are:

• Karl Ernst von Baer
• Charles Darwin
• Jan Ingenhousz

If you are asking in relation to important careers in Biology, then you options are varied. Many people who study Biology continue in the Medical field and become a Doctor of Medicine, but they are many other options.

If you study Biology you can work as a:

• Biological Technician: Do research in a lab and help discover new advancements.
• Biochemist: Play a key role in the fast-growing fields of biotechnology and biomedical research.
• Genetic Counselor: Assess the genetic makeup of clients, and communicate with them about the risk of transmitting a genetic disease or disability to their offspring
• Health communications specialists: Responsible for educating communities about health concerns, particularly public health issues, including communicable diseases, health management, and healthy living
• ​Health educators: Teach people about certain practices and behaviors that promote wellness
• Pharmaceutical or medical product sales representatives: Sell medical supplies, IT products, medicines, and more to hospitals, clinics, and other medical practices
• Physician assistants and nurse practitioners: Are in high demand as front-line service providers
• Medical and health services managers: Interact with health service professionals and communicate with them about scientific policies and procedures
• Lawyer: Biology majors can excel in many areas of the law that draw on scientific knowledge and reasoning
• Financial analysts: Evaluate stocks, bonds, mutual funds, and other investments for clients and businesses. Biology majors can use their advanced mathematical skills to help assess the success of various investments

Here's a helpful link with more info.

Studying Biology can open many doors for you from being a Doctor of Medicine to the ones listed above and they are all important in different ways. Hope any of them interest you.