Introduction
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Biology is the scientific study of life. It is a natural science with a broad scope but has several unifying themes that tie it together as a single, coherent field. For instance, all organisms are made up of cells that process hereditary information encoded in genes, which can be transmitted to future generations. Another major theme is evolution, which explains the unity and diversity of life. Energy processing is also important to life as it allows organisms to move, grow, and reproduce. Finally, all organisms are able to regulate their own internal environments.
Biologists are able to study life at multiple levels of organization, from the molecular biology of a cell to the anatomy and physiology of plants and animals, and evolution of populations. Hence, there are multiple subdisciplines within biology, each defined by the nature of their research questions and the tools that they use. Like other scientists, biologists use the scientific method to make observations, pose questions, generate hypotheses, perform experiments, and form conclusions about the world around them.
Life on Earth, which emerged more than 3.7 billion years ago, is immensely diverse. Biologists have sought to study and classify the various forms of life, from prokaryotic organisms such as archaea and bacteria to eukaryotic organisms such as protists, fungi, plants, and animals. These various organisms contribute to the biodiversity of an ecosystem, where they play specialized roles in the cycling of nutrients and energy through their biophysical environment. (Full article...)
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A microorganism, or microbe, is an organism of microscopic size, which may exist in its single-celled form or as a colony of cells.
The possible existence of unseen microbial life was suspected from ancient times, such as in Jain scriptures from sixth century BC India. The scientific study of microorganisms began with their observation under the microscope in the 1670s by Anton van Leeuwenhoek. In the 1850s, Louis Pasteur found that microorganisms caused food spoilage, debunking the theory of spontaneous generation. In the 1880s, Robert Koch discovered that microorganisms caused the diseases tuberculosis, cholera, diphtheria, and anthrax. (Full article...)Selected picture -
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The African bullfrog (Pyxicephalus adspersus) is a species of frog in the family Pyxicephalidae.
Major topics
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For the French Napoleonic War General see Marshall Étienne Macdonald
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Did you know -
- ... that one of the smallest fish, the Philippine goby, can only grow between 1 and 1.5 cm?
- ...that the largest flower, Rafflesia has a very foul odor?
- ... that mesoporous silica nanoparticles are prepared by the Stöber process and are used in preparing biosensors and delivering medications to within cellular structures?
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Anatomy - Anthropology - Astrobiology - Biochemistry - Bioengineering - Bioinformatics - Biotechnology - Botany - Cell biology - Conservation biology - Developmental biology - Ecology - Environmental science - Evolutionary biology - Genetics - Mathematical biology - Medicine - Microbiology - Immunology - Molecular biology - Mycology - Neuroscience - Paleontology - Palynology Parasitology - Pharmacology -
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WikiProjects connected with biology:
A complete list of scientific WikiProjects can be found here. See also Wikispecies, a Wikimedia project dedicated to classification of biological species.
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