Probably, some of these questions have popped into your mind. How did you get into the world? How does your body function? What organs are inside your body? How are plants different from us, or animals? What should you eat to stay healthy? Why do we need vaccines? The number of questions might be endless.
All of these questions and so much more about life and living organisms can be answered and explained with one of the most important natural sciences. This science is called BIOLOGY.
In this lesson, we are going to learn about:
The name of this study is derived from the Greek words "bios" - meaning "life" and "logos" meaning "study", "bios"+"logos"="biology". So, simple, Biology is the study of life. It is a science that studies life and living organisms, including the structure, growth, function, evolution, distribution, or other features of living organisms.
We already know that everything around us can be living or non-living. What distinguishes the living and non-living things are the characteristics of all living organisms: order, sensitivity, reproduction, growth and development, regulation, homeostasis, and energy processing. We are living organisms, and so the plants and animals. Biology is concerned with everything involving a life form, no matter how small or large, including its structure, behavior, origin, growth, and reproduction. So, we can say that Biology is complex and very important.
Even if this science is so complex, there are unifying concepts that consolidate it into a single and coherent field:
This theory is that living organisms are made up of cells; that the cells are the basic structural/organizational unit of all organisms, and that all cells come from pre-existing cells.
Genetics is a science of heredity. It is a study of genes, which are the basic physical and functional units of heredity, and its role in inheritance. Genetics explains how certain traits or conditions are passed down from one generation to another. Genetics involves scientific studies of genes, as well as, their effects.
The theory of evolution postulates that all organisms on the Earth have descended from a common ancestor. The great variations of life found on Earth now can be explained with the help of evolution. Evolution is relevant to the understanding of the organization of current life forms. It is also relevant to the understanding of the natural history of life forms. That is why evolution is central to all fields of biology.
The survival of a living organism depends on the continuous input of energy. Living organisms need the energy to perform their metabolic activities. Some of the organisms take the energy from the sun and then convert it into chemical energy in food. But, there are also organisms that use chemical energy from the molecules they take in. The organisms responsible for the introduction of energy into an ecosystem are known as producers or autotrophs.
To function properly, cells require appropriate conditions which are not constant (temperature, ph, etc). But, despite the changes in the environment, organisms are able to maintain internal conditions within a narrow range. This process is called homeostasis. All living organisms, whether unicellular or multicellular, exhibit homeostasis.
The origins of modern biology are traced back to ancient Greece. It was Aristotle, Greek philosopher, and polymath (384–322 BC), who contributed most extensively to the development of biology. Especially important is his work named History of Animals. From here, Aristotle can be regarded as the father of biology. Biology began to quickly develop and grow with Anton van Leeuwenhoek's dramatic improvement of the microscope. In that time scholars discovered spermatozoa, bacteria, infusoria, and the diversity of microscopic life. In the early 19th century, a number of biologists pointed to the central importance of the cell and in 1838, Schleiden and Schwann began promoting the now universal ideas of the cell theory. Jean-Baptiste Lamarck was the first to present a coherent theory of evolution. The British naturalist Charles Darwin spread the theory of natural selection throughout the scientific community. In 1953, the discovery of the double-helical structure of DNA marked the transition to the era of molecular genetics.
The field of study in Biology is huge. Biology, today, has so many branches and sub-disciplines. Some of them are:
Since we are living organisms, biology can be of big help in explaining and understanding the various phenomena around and within us. Biology gives us knowledge and understanding of the world. Biology is important because it can help us:
