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plural: biologies


The branch of science concerned with the structure, function, growth, evolution, and distribution of organisms



Science is defined as the systematic study of a phenomenon in the form of hypotheses, theories, principles, models or laws that have been conclusively drawn from observed or verifiable facts or from experimental findings gained basically from the application of the scientific method. One of the branches of science is biology.

Biology is the branch of science that studies and deals with organisms. It encompasses various aspects of an organism, such as structure, function, growth, evolution, and distribution. An organism pertains to any entity that is capable of reacting to stimuli, reproduction, growth, and homeostasis. It includes viruses, bacteria, protists, fungi, plants, and animals. These organisms possess distinct characteristics that they may be classified into hierarchical groups or taxonomic levels. There are eight major taxonomic levels: domain, kingdom, phyla, class, order, family, genus, and species. The three-domain system of biological classification as proposed by Carl Woese and others (in 1977) classifies organisms into the following domains: archaea (archaeabacteria), bacteria (eubacteria), and eucarya (eukaryotes). Both domains archaea and bacteria are prokaryotes.

Branches of biology

Biology encompasses various sub-disciplines or branches. Some of the branches of biology are as follows:

  • Anatomy - study of the animal form, particularly human body
  • Astrobiology - branch of biology concerned with the effects of outer space on living organisms and the search for extraterrestrial life
  • Biochemistry - the study of the structure and function of cellular components, such as proteins, carbohydrates, lipids, nucleic acids, and other biomolecules, and of their functions and transformations during life processes
  • Bioclimatology - a science concerned with the influence of climates on organisms, for instance the effects of climate on the development and distribution of plants, animals, and humans
  • Bioengineering - or biological engineering, a broad-based engineering discipline that deals with bio-molecular and molecular processes, product design, sustainability and analysis of biological systems
  • Biogeography - a science that attempts to describe the changing distributions and geographic patterns of living and fossil species of plants and animals
  • Bioinformatics - information technology as applied to the life sciences, especially the technology used for the collection, storage, and retrieval of genomic data
  • Biomathematics - mathematical biology or biomathematics, an interdisciplinary field of academic study which aims at modeling natural, biological processes using mathematical techniques and tools. It has both practical and theoretical applications in biological research
  • Biophysics - or biological physics, an interdisciplinary science that applies the theories and methods of physical sciences to questions of biology
  • Biotechnology - applied science concerned with biological systems, living organisms, or derivatives thereof, to make or modify products or processes for specific use
  • Botany - the scientific study of plants
  • Cell biology - the study of cells at the microscopic or at the molecular level. It includes studying the cells’ physiological properties, structures, organelles, interactions with their environment, life cycle, cell division, and apoptosis
  • Chronobiology - a science that studies time-related phenomena in living organisms
  • Conservation Biology - concerned with the studies and schemes of habitat preservation and species protection for the purpose of alleviating extinction crisis and conserving biodiversity
  • Cryobiology - the study of the effects of low temperatures on living organisms
  • Developmental Biology - the study of the processes by which an organism develops from a zygote to its full structure
  • Ecology - the scientific study of the relationships between plants, animals, and their environment
  • Ethnobiology - a study of the past and present human interactions with the environment, for instance, the use of diverse flora and fauna by indigenous societies
  • Evolutionary Biology - a subfield concerned with the origin and descent of species, as well as their change over time, i.e. their evolution
  • Freshwater Biology - a science concerned with the life and ecosystems of freshwater habitats
  • Genetics - a science that deals with heredity, especially the mechanisms of hereditary transmission and the variation of inherited characteristics among similar or related organisms
  • Geobiology - a science that combines geology and biology to study the interactions of organisms with their environment
  • Immunobiology - a study of the structure and function of the immune system, innate and acquired immunity, the bodily distinction of self from non-self, and laboratory techniques involving the interaction of antigens with specific antibodies
  • Marine Biology - study of ocean plants and animals and their ecological relationships
  • Medicine - the science which relates to the prevention, cure, or alleviation of disease
  • Microbiology - the branch of biology that deals with microorganisms and their effects on other living organisms
  • Molecular Biology - the branch of biology that deals with the formation, structure, and function of macromolecules essential to life, such as nucleic acids and proteins, and especially with their role in cell replication and the transmission of genetic information
  • Mycology - the study of fungi
  • Neurobiology - the branch of biology that deals with the anatomy, physiology, and pathology of the nervous system
  • Paleobiology - the study of the forms of life existing in prehistoric or geologic times, as represented by the fossils of plants, animals, and other organisms
  • Parasitology - the study of parasites and parasitism
  • Pathology - the study of the nature of the disease and its causes, processes, development, and consequences
  • Pharmacology - the study of preparation and use of drugs and synthetic medicines
  • Physiology - the biological study of the functions of living organisms and their parts
  • Protistology - the study of protists
  • Psychobiology - the study of mental functioning and behavior in relation to other biological processes
  • Toxicology - the study of how natural or man-made poisons cause undesirable effects in living organisms
  • Virology - study of viruses
  • Zoology - The branch of biology that deals with animals and animal life, including the study of the structure, physiology, development, and classification of animals
    • Ethology - the study of animal behavior
    • Entomology - the scientific study of insects
    • Ichthyology - the study of fishes
    • Herpetology - the science of reptiles and amphibians
    • Ornithology - the science of birds
    • Mammalogy - the study of mammals
    • Primatology - the science that deals with primates


A specialist or an expert in the field of biology is called a biologist. Biologists study life on various structural levels. They look upon the biophysical, biomolecular, cellular, and systemic levels of an organism. They attempt to understand the mechanisms at play in various biological processes that govern life. They are also interested in coming up with innovations to create and improve life.

Biological research is a vast field. It attempts to understand the biological mechanisms happening within an organism. It also explores the interactions that occur between the organism and its environment. Thus, the sites of research also vary. Biologists may be found conducting research inside a laboratory. Others carry out their scientific pursuits outside, such as in diverse habitats where an organism or a population of organisms thrive. Furthermore, research on biology also attempts to discover plausible biological applications in other fields, such as in medicine and in the industry.



  • Greek: βίος (bios, "life") + Greek: λογία (logia, "study of")


  • biol.


  • biological science
  • life science

Derived terms

Further reading

See also

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