Molecular and Cellular Biologists

The biological sciences have developed slowly throughout the course of human history. Early civilizations practiced a form of biology when they established agriculture. It was an inexact science as they could only determine the types of seeds to plant based on their observations of the soil and climate, and their past experiences of successful harvests.

Biology became an exact science in modern times. People learned how to identify desirable plants (taxonomy) and habitable environments (ecology), how to domesticate plants (agronomy and horticulture) and animals (animal husbandry), and how to eat a suitable diet (nutrition). Plants and animals were eventually classified, and early scientists studied their functions and relationships to their environment and other organisms around them. This was the beginning of zoology (animal science) and botany (plant science).

One of the first documented taxonomic systems for animals was created by the Greek philosopher Aristotle. He distinguished animals as two types: blooded (mammals, birds, amphibians, reptiles, and fishes) and bloodless (insects, crustaceans, and other lower animals). He also studied reproduction and theorized, incorrectly, how embryos developed in animals.

The Arabs and Persians made important advances in biological understanding from the second through the 11th century. Unlike the Europeans, they continued to study from the base of knowledge established by the Greeks. Persian philosopher and physician Avicenna wrote the Canon of Medicine, among the most influential and important publications on medical knowledge in the world at its time—and for the next seven centuries.

The field of biology has expanded rapidly in the past 200 years. French physician Louis Pasteur developed the field of immunology, and his studies of fermentation led to modern microbiology. Improvements in the microscope contributed to many other achievements, allowing scientists to isolate much smaller structures than ever before possible. Matthias Schleiden and Theodor Schwann formulated the idea that the cell is the fundamental unit of all organisms. Gregor Mendel discovered the principles of heredity through crossbreeding pea plants.

The 19th century can be considered the age of cellular biology, however, biochemistry and molecular biology studies and breakthroughs have dominated the 20th and early 21st centuries. The discovery of the atomic structure allowed the fundamental building blocks of nature to be studied. Living tissues were found to be composed of fats, sugars, and proteins, and proteins were found to be composed of amino acids. Discoveries in cell biology established the manner in which information was transmitted from one organism to its progeny. Chromosomes were recognized as the carriers of this information. In 1944, Oswald Avery and a team of scientists were able to isolate and identify DNA as the transmitter of genetic information. In 1953, James Watson and Francis Crick deciphered the complex structure of DNA and hypothesized that it carried the genetic code for all living matter.

Biotechnology advances now enable biologists and other scientists to study and manipulate the DNA of plants and animals to create healthier organisms and more productive yields, as well as seek cures to human diseases. Biological scientists are also using biotechnology in agriculture and environmental remediation. The work of molecular and cellular biologists helps to improve the health and quality of life of people and animals and to help us have a better understanding of biological processes in relation to the world around us.