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Biology

Biology is the branch of science Science

Science in the broadest sense refers to any system of knowledge attained by verifiable means.... 

 dealing with the study of life. It is concerned with the characteristics, classification, and behaviors of organism Organism

In biology [i] and ecology [i], an organism is a living [i] complex adaptive system [i] ... 

s, how species come into existence, and the interactions they have with each other and with the natural environment Natural environment

The natural environment comprises all living and non-living things that occur naturally [i] on Earth [i] ... 

. Biology encompasses a broad spectrum of academic fields List of academic disciplines

This is a list of academic disciplines.... 

 that are often viewed as independent disciplines. However, together they address phenomena related to living organisms over a wide range of scales, from biophysics to ecology Ecology

Ecology, or ecological science, is the scientific study of the distribution and abundance of living organisms [i] ... 

. All concepts in biology are subject to the same laws that other branches of science obey, such as the laws of thermodynamics Thermodynamics

Thermodynamics is a branch of physics [i] that studies the effects of changes in temperature [i], pressure [i] ... 

 and conservation of mass.

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Timeline

1802   Treviranus Gottfried Reinhold Treviranus

Gottfried Reinhold Treviranus was a German [i] naturalist [i]. ... 

 uses the term biology for the first time.



Encyclopedia

Biology is the branch of science Science

Science in the broadest sense refers to any system of knowledge attained by verifiable means.... 

 dealing with the study of life. It is concerned with the characteristics, classification, and behaviors of organism Organism

In biology [i] and ecology [i], an organism is a living [i] complex adaptive system [i] ... 

s, how species come into existence, and the interactions they have with each other and with the natural environment Natural environment

The natural environment comprises all living and non-living things that occur naturally [i] on Earth [i] ... 

. Biology encompasses a broad spectrum of academic fields List of academic disciplines

This is a list of academic disciplines.... 

 that are often viewed as independent disciplines. However, together they address phenomena related to living organisms over a wide range of scales, from biophysics to ecology Ecology

Ecology, or ecological science, is the scientific study of the distribution and abundance of living organisms [i] ... 

. All concepts in biology are subject to the same laws that other branches of science obey, such as the laws of thermodynamics Thermodynamics

Thermodynamics is a branch of physics [i] that studies the effects of changes in temperature [i], pressure [i] ... 

 and conservation of mass.

At the organism level, biology has partially explained phenomena such as birth Childbirth

Childbirth is the culmination of a human [i] pregnancy [i] with the emergence of a newborn infant [i] fr ... 

, growth, aging Ageing

Ageing or aging is the process of becoming older.... 

, death Death

Death is the full cessation of vital functions [i] in the biological life [i]. ... 

 and decay Decomposition

Decomposition is a phenomenon common in the sciences of biology [i] and chemistry [i]. ... 

 of living organisms, similarities between offspring and their parents and flowering of plants which have puzzled humanity throughout history. Other phenomena, such as lactation Lactation

Lactation describes the secretion of milk [i] from the mammary glands [i], the process of providing that ... 

, metamorphosis Metamorphosis

Metamorphosis is a biological process [i] by which an animal [i] physically develops [i]... 

, egg-hatching, healing, and tropism Tropism

A tropism is a biological phenomenon [i], indicating growth or turning movement of a biological organism [i] ... 

 have been addressed. On a wider scale of time and space, biologists have studied domestication Domestication

Domestication, also called taming, is a phenomenon whereby a wild biological [i] organism ... 

 of animals and plants, the wide variety of living organisms , changes in living organisms over time , extinction Extinction

In biology [i] and ecology [i], extinction is the cessation of existence of a species [i] or group of taxa [i]... 

, speciation Speciation

Speciation is the theory of the evolution [i]ary process by which new biological species [i] are believe ... 

, social behaviour among animals, etc.

While botany Botany

Botany is the scientific study [i] of plant [i]life [i]. ... 

 encompasses the study of plants, zoology Zoology

Zoology is the biological [i] discipline [i] which involves the study of animal [i] ... 

 is the branch of science that is concerned about the study of animals and anthropology Anthropology

Anthropology consists of the study of humanity [i] . ... 

 is the branch of biology which studies human beings. However, at the molecular Molecule

In chemistry, a molecule is an aggregate of two or more atom [i]s in a definite arrangement held togethe ... 

 scale, life is studied in the disciplines of molecular biology Molecular biology

Molecular biology is the study of biology [i] at a molecular [i] level. ... 

, biochemistry Biochemistry

Biochemistry is the study of the chemical processes and chemical transformations in living organism [i]s ... 

, and molecular genetics. More fundamental than these fields is biophysics which deals with energy within biological systems. At the next level, that of the cell, it is studied in cell biology Cell biology

Cell biology is an academic discipline [i] that studies cell [i]s. ... 

. At the multicellular scale, it is examined in physiology, anatomy Anatomy

Anatomy , is the branch of biology [i] that deals with the structure and organization of living things [i] ... 

, and histology Histology

Histology is the study of tissue [i] sectioned as a thin slice, using a microtome [i] ... 

. Developmental biology Developmental biology

Developmental biology is the study of the process by which organisms grow and develop.... 

 studies life at the level of an individual organism's development or ontogeny. Moving up the scale towards more than one organism, genetics considers how heredity works between parent and offspring. Ethology considers the behaviour of groups of organisms. Population genetics looks at the level of an entire population Population

In sociology [i] and biology [i], a population is the collection of people [i], or organism [i] ... 

, and systematics considers the multi-species scale of lineages. Interdependent populations and their habitats are examined in ecology Ecology

Ecology, or ecological science, is the scientific study of the distribution and abundance of living organisms [i] ... 

 and evolutionary biology. A speculative new field is astrobiology , which examines the possibility of life beyond the Earth.

Principles of biology

Unlike physics Physics

Physics , the most fundamental physical science [i], is concerned with the underlying principles of the ... 

, biology does not usually describe systems in terms of objects which obey immutable physical laws described by mathematics Mathematics

Mathematics is the discipline that deals with concepts such as quantity [i], structure [i], space [i] a ... 

. Biological systems are not completely random, however, as they may have predictable statistical Statistics

Statistics is a mathematical science [i] pertaining to the collection, analysis, interpretat... 

 tendencies to behave in certain ways, but these tendencies are usually not as concrete as those described in subjects such as physics. Nevertheless, the biological sciences are characterized and unified by several major underlying principles and concepts: universality, evolution Evolution

In biology [i], evolution is the change in the heritable [i] traits [i] of a population [i] ... 

, diversity, continuity Continuity

Continuity may mean:
  • In mathematics:

... 

, genetics, homeostasis Homeostasis

Homeostasis is the property of an open system [i], especially living organism [i]s, to regu ... 

, and interactions.

However, biology is still considered to be subject to the same physical laws that other branches of science obey, such as the laws of thermodynamics and conservation of mass.

Universality: Biochemistry, cells, and the genetic code



Some striking examples of biological universality include life's carbon Carbon

Carbon is a chemical element [i] in the periodic table [i] that has the symbol [i] C' ... 

-based biochemistry Biochemistry

Biochemistry is the study of the chemical processes and chemical transformations in living organism [i]s ... 

 and its ability to pass on characteristics via genetic material, using a DNA and RNA based genetic code Genetic code

The genetic code is the set of rules by which information encoded in genetic material is translated int... 

 with only minor variations across all living things.

Another universal principle is that all organism Organism

In biology [i] and ecology [i], an organism is a living [i] complex adaptive system [i] ... 

s are made of cells. Similarly, all organisms share common developmental processes. For example, in most animals, the basic stages of early embryo Embryo

An embryo is a multicellular [i] diploid [i] eukaryote [i] in its earliest stage of development [i] ... 

nic development share similar morphological characteristics and include similar gene Gene

A gene is the unit of heredity [i] in living organisms [i].... 

s.

Evolution: The central principle of biology


The central organizing concept in biology is that all life has a common origin and has changed and developed through the process of evolution Evolution

In biology [i], evolution is the change in the heritable [i] traits [i] of a population [i] ... 

 . This has led to the striking similarity of units and processes discussed in the previous section. Charles Darwin Charles Darwin

Charles Robert Darwin was an English [i] naturalist [i] who achieved lasting fa ... 

 established evolution as a viable theory by articulating its driving force, natural selection Natural selection

Natural selection is the process by which individual organism [i]s with favorable trait [i]s are... 

 . Genetic drift was embraced as an additional mechanism of evolutionary development in the modern synthesis Modern evolutionary synthesis

The modern evolutionary synthesis, generally denotes the integration of Charles Darwin [i]'s theory of t ... 

 of the theory.

The evolutionary history of a species— which describes the characteristics of the various species from which it descended— together with its genealogical relationship to every other species is called its phylogeny. Widely varied approaches to biology generate information about phylogeny. These include the comparisons of DNA sequence DNA sequence

A DNA sequence or genetic sequence is a succession of letters representing the primary structure [i] ... 

s conducted within molecular biology Molecular biology

Molecular biology is the study of biology [i] at a molecular [i] level. ... 

 or genomics, and comparisons of fossil Fossil

Fossils are the mineral [i]ized or otherwise preserved remains or traces of animals, plants, and other ... 

s or other records of ancient organisms in paleontology Paleontology

Paleontology or palaeontology is the study of the developing history of life [i] on Earth [i], in... 

. Biologists organize and analyze evolutionary relationships through various methods, including phylogenetics, phenetics, and cladistics Cladistics

Cladistics is a branch of biology [i] that determines the evolution [i]ary relationships between organis ... 

 .


Diversity: The variety of living organisms



Despite its underlying unity, life exhibits an astonishingly wide diversity in morphology, behavior, and life histories. In order to grapple with this diversity, biologists attempt to classify all living things. Scientific classification seeks to reflect the evolutionary trees of the organism being classified. Classification is the province of the disciplines of systematics and taxonomy Alpha taxonomy

Taxonomy, sometimes alpha taxonomy, is the science [i] of finding, describing and naming [i] ... 

. Taxonomy places organisms in groups called taxa, while systematics seeks to define their relationships with each other. This classification technique has evolved to reflect advances in cladistics Cladistics

Cladistics is a branch of biology [i] that determines the evolution [i]ary relationships between organis ... 

 and genetics, shifting the focus from physical similarities and shared characteristics to phylogenetics.

Traditionally, living things have been divided into five kingdoms:

Monera Monera

Monera is an obsolete biological kingdom [i] that comprised most living things with a prokaryotic [i] ... 

 -- Protist Protist

Protists are a heterogeneous [i] group of organisms, comprising those eukaryote [i]s that are not animal [i] ... 

a -- Fungi Fungus

A fungus is a eukaryotic [i] organism [i] that digests its food [i] externally and absorbs th ... 

 -- Plant Plant

Plants are a major group of living things [i] including familiar organism [i]s such as tree [i]s, flower [i] ... 

ae -- Animal Animal

Animals are a major group of organism [i]s, classified as the kingdom [i] Animalia or ... 

ia


However, many scientists now consider this five-kingdom system to be outdated. Modern alternative classification systems generally begin with the three-domain system Three-domain system

The three-domain system is a biological classification introduced by Carl Woese [i] in 1990 that emphasi ... 

:

Archaea Archaea

Archaea , also called Archaebacteria , is a major division of living [i] organism [i]s. ... 

  -- Bacteria Bacteria

Bacteria are a major group of living organism [i]s. ... 

  -- Eukaryota Eukaryote

|-

| style = "background: pink; padding: 4px;" | Animal [i]ia - Animals
... 



These domains reflect whether the cells have nuclei or not, as well as differences in the cell exteriors.

Further, each kingdom is broken down continuously until each species is separately classified. The order is 1) Kingdom, 2) Phylum, 3) Class, 4) Order, 5) Family, 6) Genus, 7) Species. The scientific name of an organism is obtained from its Genus and Species. For example, humans would be listed as Homo sapiens. Homo would be the Genus and Sapiens is the species. Whenever writing the scientific name of an organism it is proper to capitalize the first letter in the genus and put all of the species in lowercase; in addition the entire term would be put in italics. The term used for classification is called Taxonomy.

There is also a series of intracellular parasites that are progressively "less alive" in terms of metabolic Metabolism

[i]s in [[life|living]... 

 activity:

Viruses Virus

A virus is a microscopic [i] particle that can infect [i] the cell [i]s of a ... 

 -- Viroid Viroid

Pospiviroidae [i]

Avsunviroidae [i]
... 

s -- Prion Prion

A prion — short for proteinaceous infectious particle — ; is a type of infectious agent [i] ... 

s

Continuity: The common descent of life


Up into the 19th century 19th century

The 19th century lasted from 1801 [i] through 1900 [i] in the Gregorian calendar [i].
... 

, it was commonly believed that life forms could appear spontaneously under certain conditions . This misconception was challenged by William Harvey William Harvey

William Harvey was a medical doctor [i] who is credited with first correctly describing, in exact det... 

's diction that "all life [is] from [an] egg" , a foundational concept of modern biology. It simply means that there is an unbroken continuity of life from its initial origin to the present time.

A group of organisms is said to share a common descent if they share a common ancestor. All organism Organism

In biology [i] and ecology [i], an organism is a living [i] complex adaptive system [i] ... 

s on the Earth Earth

Earth is the third planet [i] in the solar system [i] in terms of distance from the Sun [i], and the fi ... 

 have been and are descended from a common ancestor or an ancestral gene pool. This last universal common ancestor of all organisms is believed to have appeared about 3.5 billion years ago Timeline of evolution

This timeline of the evolution of life outlines the major events in the development of life [i] on the p... 

. Biologists generally regard the universality of the genetic code Genetic code

The genetic code is the set of rules by which information encoded in genetic material is translated int... 

 as definitive evidence in favor of the theory of universal common descent for all bacteria Bacteria

Bacteria are a major group of living organism [i]s. ... 

, archaea Archaea

Archaea , also called Archaebacteria , is a major division of living [i] organism [i]s. ... 

, and eukaryote Eukaryote

|-
| style = "background: pink; padding: 4px;" | Animal [i]ia - Animals
... 

s .

Homeostasis: Adapting to change


Homeostasis is the ability of an open system to regulate its internal environment to maintain a stable condition by means of multiple dynamic equilibrium adjustments controlled by interrelated regulation mechanisms. All living organism Organism

In biology [i] and ecology [i], an organism is a living [i] complex adaptive system [i] ... 

s, whether unicellular Microorganism

A microorganism or microbe is an organism [i] that is microscopic [i] . ... 

 or multicellular, exhibit homeostasis. Homeostasis manifests itself at the cellular level through the maintenance of a stable internal acidity ; at the organismic level, warm-blooded Warm-blooded

Warm-blooded animal [i]s maintain thermal homeostasis [i]; that is, they keep their core body temperature [i]... 

 animals maintain a constant internal body temperature; and at the level of the ecosystem, as when atmospheric carbon dioxide Carbon dioxide

Carbon dioxide is a chemical compound [i] composed of one carbon [i] and two oxygen [i] atoms. ... 

 levels rise and plant Plant

Plants are a major group of living things [i] including familiar organism [i]s such as tree [i]s, flower [i] ... 

s are theoretically able to grow healthier and remove more of the gas from the atmosphere. Tissues and organs can also maintain homeostasis.

Interactions: Groups and environments



Every living thing interacts with other organisms and its environment Natural environment

The natural environment comprises all living and non-living things that occur naturally [i] on Earth [i] ... 

. One reason that biological systems can be difficult to study is that so many different interactions with other organisms and the environment are possible, even on the smallest of scales. A microscopic bacterium Bacteria

Bacteria are a major group of living organism [i]s. ... 

 responding to a local sugar gradient is responding to its environment as much as a lion Lion

The lion is a mammal [i] of the family Felidae [i] and one of four "big cat [i]s" in the genus [i] Panthera [i] ... 

 is responding to its environment when it searches for food in the Africa Africa

Africa is one of the greatest sized continents of the Earth.... 

n savanna Savanna

A savanna or savannah is a grassland [i] with widely spaced trees, and occurs in several types of... 

h. For any given species, behaviors can be co-operative, aggressive Aggression

In psychology [i], aggression encompasses many different types of social behavior [i], some of which are... 

, parasitic or symbiotic Symbiosis

In some cases, the term symbiosis is used only if the association is obligatory and benefits both organisms.... 

. Matters become more complex when two or more different species interact in an ecosystem. Studies of this type are the province of ecology Ecology

Ecology, or ecological science, is the scientific study of the distribution and abundance of living organisms [i] ... 

.

Scope of biology


Biology has become such a vast research enterprise that it is not generally regarded as a single discipline, but as a number of clustered sub-disciplines. This article considers four broad groupings. The first group consists of those disciplines that study the basic structures of living systems: cells, gene Gene

A gene is the unit of heredity [i] in living organisms [i].... 

s etc.; the second group considers the operation of these structures at the level of tissues, organs, and bodies; the third group considers organisms and their histories; the final constellation of disciplines focuses on their interactions. It is important to note, however, that these boundaries, groupings, and descriptions are a simplified characterization of biological research. In reality, the boundaries between disciplines are fluid, and most disciplines frequently borrow techniques from each other. For example, evolutionary biology leans heavily on techniques from molecular biology to determine DNA sequence DNA sequence

A DNA sequence or genetic sequence is a succession of letters representing the primary structure [i] ... 

s, which assist in understanding the genetic variation of a population; and physiology borrows extensively from cell biology in describing the function of organ systems.


Structure of life



Molecular biology Molecular biology

Molecular biology is the study of biology [i] at a molecular [i] level. ... 

 is the study of biology at a molecular Molecule

In chemistry, a molecule is an aggregate of two or more atom [i]s in a definite arrangement held togethe ... 

 level. This field overlaps with other areas of biology, particularly with genetics and biochemistry Biochemistry

Biochemistry is the study of the chemical processes and chemical transformations in living organism [i]s ... 

. Molecular biology chiefly concerns itself with understanding the interactions between the various systems of a cell, including the interrelationship of DNA, RNA, and protein synthesis and learning how these interactions are regulated.

Cell biology Cell biology

Cell biology is an academic discipline [i] that studies cell [i]s. ... 

 studies the physiological properties of cells, as well as their behaviors, interactions, and environment Natural environment

The natural environment comprises all living and non-living things that occur naturally [i] on Earth [i] ... 

. This is done both on a microscopic Microscope

A microscope is an instrument for viewing objects that are too small to be seen by the naked or unaided... 

 and molecular Molecule

In chemistry, a molecule is an aggregate of two or more atom [i]s in a definite arrangement held togethe ... 

 level. Cell biology researches both single-celled organisms like bacteria Bacteria

Bacteria are a major group of living organism [i]s. ... 

 and specialized cells in multicellular organisms like human Human

Humans, or human beings, are biped [i]al primate [i]s belonging to the mammal [i]ian species ... 

s.

Understanding cell composition and how they function is fundamental to all of the biological sciences. Appreciating the similarities and differences between cell types is particularly important in the fields of cell and molecular biology. These fundamental similarities and differences provide a unifying theme, allowing the principles learned from studying one cell type to be extrapolated and generalized to other cell types.

Genetics is the science Science

Science in the broadest sense refers to any system of knowledge attained by verifiable means.... 

 of gene Gene

A gene is the unit of heredity [i] in living organisms [i].... 

s, heredity, and the variation of organism Organism

In biology [i] and ecology [i], an organism is a living [i] complex adaptive system [i] ... 

s. In modern research, genetics provides important tools in the investigation of the function of a particular gene, or the analysis of genetic interaction Epistasis

Epistasis takes place when the action of one gene [i] is modified by one or more others that assort inde ... 

s. Within organism Organism

In biology [i] and ecology [i], an organism is a living [i] complex adaptive system [i] ... 

s, genetic information generally is carried in chromosome Chromosome

A chromosome is a large macromolecule [i] into which DNA [i] is normally packaged in a cell [i].... 

s, where it is represented in the chemical structure DNA sequence

A DNA sequence or genetic sequence is a succession of letters representing the primary structure [i] ... 

 of particular DNA DNA

Deoxyribonucleic acid is a nucleic acid [i] that contains the genetic [i] instructions for t... 

 molecule Molecule

In chemistry, a molecule is an aggregate of two or more atom [i]s in a definite arrangement held togethe ... 

s.

Gene Gene

A gene is the unit of heredity [i] in living organisms [i].... 

s encode the information necessary for synthesizing proteins, which in turn play a large role in influencing the final phenotype of the organism.

Developmental biology studies the process by which organisms grow and develop. Originating in embryology, modern developmental biology studies the genetic control of cell growth Cell growth

The term cell growth is used in two different ways in biology [i].
... 

, differentiation Cellular differentiation

*Multipotent [i]
  • Germ layer [i] ... 

    , and "morphogenesis Morphogenesis

    Morphogenesis [i] is also the name of a band.

... 

," which is the process that gives rise to tissues, organs, and anatomy Anatomy

Anatomy , is the branch of biology [i] that deals with the structure and organization of living things [i] ... 

.
Model organism Model organism

A model organism is a species [i] that is extensively studied to understand particular biological [i] ... 

s for developmental biology include the round worm Caenorhabditis elegans Caenorhabditis elegans

Caenorhabditis elegans is a free-living nematode [i] , about 1 mm [i] in length, wh ... 

, the fruit fly Drosophila melanogaster Drosophila melanogaster

Drosophila melanogaster is a two-winged insect that belongs to the Diptera [i], the order [i] ... 

, the zebrafish Brachydanio rerio, the mouse Mus musculus House mouse

Mus musculus is the common house mouse.... 

, and the weed Arabidopsis thaliana Arabidopsis thaliana

Arabidopsis thaliana, commonly called arabidopsis, thale cress, or mouse-ear cress, a sm... 

.

Physiology of organisms

Main articles: Physiology, Anatomy Anatomy

Anatomy , is the branch of biology [i] that deals with the structure and organization of living things [i] ... 



Physiology studies the mechanical, physical, and biochemical processes of living organisms by attempting to understand how all of the structures function as a whole. The theme of "structure to function" is central to biology. Physiological studies have traditionally been divided into plant physiology and animal physiology, but the principles of physiology are universal, no matter what particular organism Organism

In biology [i] and ecology [i], an organism is a living [i] complex adaptive system [i] ... 

 is being studied. For example, what is learned about the physiology of yeast Yeast

Yeasts are single-celled fungi [i], a few species of which are commonly used to leaven [i] ... 

 cells can also apply to human Human

Humans, or human beings, are biped [i]al primate [i]s belonging to the mammal [i]ian species ... 

 cells. The field of animal physiology extends the tools and methods of human physiology Human physiology

Human physiology is the science of the mechanical, physical, and biochemical functions of normal human [i] ... 

 to non-human species. Plant physiology also borrows techniques from both fields.

Anatomy Anatomy

Anatomy , is the branch of biology [i] that deals with the structure and organization of living things [i] ... 

 is an important branch of physiology and considers how organ systems in animals, such as the nervous, immune Immune system

The immune system is composed of a complex constellation of cells, organs and tissues, arranged in an el... 

, endocrine Endocrine system

The endocrine system is a control system of ductless gland [i]s that secrete chemical "instant messenger ... 

, respiratory Respiratory system

The respiratory system is an organ system which is used for gas exchange [i]. ... 

, and circulatory Circulatory system

A circulatory system is an organ system [i] that moves substances to and from cells [i]; i ... 

 systems, function and interact. The study of these systems is shared with medically Medicine

Medicine is the branch of health science [i] and the sector of public life concerned with maintaining or ... 

 oriented disciplines such as neurology and immunology.

Diversity and evolution of organisms



Main articles: Evolutionary biology, Biodiversity Biodiversity

Biodiversity or biological diversity is the diversity of life [i].... 

, Botany Botany

Botany is the scientific study [i] of plant [i]life [i]. ... 

, Zoology Zoology

Zoology is the biological [i] discipline [i] which involves the study of animal [i] ... 



Evolutionary biology is concerned with the origin and descent of species, as well as their change over time, and includes scientists from many taxonomically Alpha taxonomy

Taxonomy, sometimes alpha taxonomy, is the science [i] of finding, describing and naming [i] ... 

-oriented disciplines. For example, it generally involves scientists who have special training in particular organism Organism

In biology [i] and ecology [i], an organism is a living [i] complex adaptive system [i] ... 

s such as mammalogy, ornithology, or herpetology, but use those organisms as systems to answer general questions about evolution. Evolutionary biology is mainly based on paleontology Paleontology

Paleontology or palaeontology is the study of the developing history of life [i] on Earth [i], in... 

, which uses the fossil Fossil

Fossils are the mineral [i]ized or otherwise preserved remains or traces of animals, plants, and other ... 

 record to answer questions about the mode and tempo of evolution, as well as the developments in areas such as population genetics and evolutionary theory. In the 1990s 1990s

The 1990s [i] decade [i] refers to the years from 1990 [i] to 1999 [i], inclusive, sometimes informally ... 

, developmental biology Developmental biology

Developmental biology is the study of the process by which organisms grow and develop.... 

 re-entered evolutionary biology from its initial exclusion from the modern synthesis through the study of evolutionary developmental biology. Related fields which are often considered part of evolutionary biology are phylogenetics, systematics, and taxonomy Alpha taxonomy

Taxonomy, sometimes alpha taxonomy, is the science [i] of finding, describing and naming [i] ... 

.

The two major traditional taxonomically-oriented disciplines are botany Botany

Botany is the scientific study [i] of plant [i]life [i]. ... 

 and zoology Zoology

Zoology is the biological [i] discipline [i] which involves the study of animal [i] ... 

.
Botany is the scientific study of plant Plant

Plants are a major group of living things [i] including familiar organism [i]s such as tree [i]s, flower [i] ... 

s. Botany covers a wide range of scientific disciplines that study the growth, reproduction Biological reproduction

Biological reproduction is the biological process [i] by which new individual organism [i]s are produced ... 

, metabolism Metabolism

[i]s in [[life|living]... 

, development Morphogenesis

Morphogenesis [i] is also the name of a band.
... 

, diseases Phytopathology

Phytopathology or plant pathology [i] is the science [i] of diagnosing and managing plant [i] disease [i] ... 

, and evolution Evolution

In biology [i], evolution is the change in the heritable [i] traits [i] of a population [i] ... 

 of plant life.
Zoology involves the study of animal Animal

Animals are a major group of organism [i]s, classified as the kingdom [i] Animalia or ... 

s, including the study of their physiology within the fields of anatomy Anatomy

Anatomy , is the branch of biology [i] that deals with the structure and organization of living things [i] ... 

 and embryology. The common genetic and developmental mechanisms of animals and plants is studied in molecular biology Molecular biology

Molecular biology is the study of biology [i] at a molecular [i] level. ... 

, molecular genetics, and developmental biology Developmental biology

Developmental biology is the study of the process by which organisms grow and develop.... 

. The ecology Ecology

Ecology, or ecological science, is the scientific study of the distribution and abundance of living organisms [i] ... 

 of animals is covered under behavioral ecology and other fields.
Classification of life
The dominant classification system is called Linnaean taxonomy Linnaean taxonomy

Linnaean taxonomy classifies living things into a hierarchy [i], originally starting with kingdoms. ... 

, which includes ranks and binomial nomenclature. How organisms are named is governed by international agreements such as the International Code of Botanical Nomenclature , the International Code of Zoological Nomenclature , and the International Code of Nomenclature of Bacteria . A fourth Draft BioCode was published in 1997 in an attempt to standardize naming in these three areas, but it has yet to be formally adopted. The Virus cInternational Code of Virus Classification and Nomenclature  remains outside the BioCode.

Interactions of organisms


Main articles: Ecology Ecology

Ecology, or ecological science, is the scientific study of the distribution and abundance of living organisms [i] ... 

, Ethology, Behavior, Biogeography

Ecology Ecology

Ecology, or ecological science, is the scientific study of the distribution and abundance of living organisms [i] ... 

 studies the distribution and abundance of living organisms, and the interactions between organisms and their environment Natural environment

The natural environment comprises all living and non-living things that occur naturally [i] on Earth [i] ... 

. The environment of an organism includes both its habitat, which can be described as the sum of local abiotic factors such as climate Climate

The climate is commonly considered to be the weather [i] averaged over a long period of time, typically ... 

 and geology Geology

Geology anetary geology]] [i] refers to the application of geologic principles to other bodies of the solar... 

, as well as the other the organisms that share its habitat. Ecological systems are studied at several different levels, from individuals and population Population

In sociology [i] and biology [i], a population is the collection of people [i], or organism [i] ... 

s to ecosystems and the biosphere Biosphere

The biosphere is the outermost part of the planet [i]'s shell — including air [i] ... 

. As can be surmised, ecology is a science that draws on several disciplines.

Ethology studies animal Animal

Animals are a major group of organism [i]s, classified as the kingdom [i] Animalia or ... 

 behavior , and is sometimes considered a branch of zoology Zoology

Zoology is the biological [i] discipline [i] which involves the study of animal [i] ... 

. Ethologists have been particularly concerned with the evolution Evolution

In biology [i], evolution is the change in the heritable [i] traits [i] of a population [i] ... 

 of behavior and the understanding of behavior in terms of the theory of natural selection Natural selection

Natural selection is the process by which individual organism [i]s with favorable trait [i]s are... 

. In one sense, the first modern ethologist was Charles Darwin Charles Darwin

Charles Robert Darwin was an English [i] naturalist [i] who achieved lasting fa ... 

, whose book The expression of the emotions in animals and men influenced many ethologists.

Biogeography studies the spatial distribution of organisms on the Earth Earth

Earth is the third planet [i] in the solar system [i] in terms of distance from the Sun [i], and the fi ... 

, focusing on topics like plate tectonics Plate tectonics

Plate tectonics is a theory [i] of geology [i] developed to explain the observed evidence for large sca ... 

, climate change Climate change

Climate change refers to the variation in the Earth [i]'s global climate [i] or in regional climates ove ... 

, dispersal and migration, and cladistics Cladistics

Cladistics is a branch of biology [i] that determines the evolution [i]ary relationships between organis ... 

.

History of the word "biology"

Formed by combining the Greek  ', meaning 'life', and ', meaning 'study of', the word "biology" in its modern sense seems to have been introduced independently by Gottfried Reinhold Treviranus Gottfried Reinhold Treviranus

Gottfried Reinhold Treviranus was a German [i] naturalist [i]. ... 

  and by Jean-Baptiste Lamarck Jean-Baptiste Lamarck

Jean-Baptiste Pierre Antoine de Monet, Chevalier de Lamarck was a French [i] naturalist and an ea ... 

 . The word itself is sometimes said to have been coined in 1800 by Karl Friedrich Burdach, but it appears in the title of Volume 3 of Michael Christoph Hanov's Philosophiae naturalis sive physicae dogmaticae: Geologia, biologia, phytologia generalis et dendrologia, published in 1766.

History

Major discoveries in biology include:
  • Cell theory Cell theory

    Cell theory is a scientific theory [i] that is one of the foundations of biology [i]. ... 

  • Germ theory of disease
  • Genetics
  • Evolution Evolution

    In biology [i], evolution is the change in the heritable [i] traits [i] of a population [i] ... 

  • DNA DNA

    Deoxyribonucleic acid is a nucleic acid [i] that contains the genetic [i] instructions for t... 



External links


  • : Daily updated biology news & community website.
  • : Major biology forum, dictionary and collection of tutorials and articles.
  • : Research News and Articles from Biological Science and related fields.
  • : A proposal for organism naming.
  • PhyloCode PhyloCode

    The PhyloCode is a developing draft for a formal set of rules governing phylogenetic [i] nomenclature [i] ... 

    , http://www.ohiou.edu/phylocode/index.html
  • : A multi-authored, distributed Internet project containing information about phylogeny and biodiversity.
  • Bioscience research journals.
  • Protocols, graduate school information, hard to find definitions.



Journal Links
  • A peer-reviewed, open-access journal published by the Public Library of Science
  • A biological journal publishes peer-reviewed scientific papers of significance


See also


Topics related to biology
People and historyBiologist - Notable biologists - History of biology History of biology

The history of biology traces man's understanding of the living world [i] from the earliest recorde ... 

 - Nobel Prize in Physiology or Medicine - Timeline of biology and organic chemistry - List of geneticists and biochemists
Institutions, publicationsNASA Ames Research Center NASA Ames Research Center

NASA Ames Research Center is a NASA [i] facility located at Moffett Federal Airfield [i], which spans t ... 

 - Bachelor of Science - Publications
Terms and phrasesOmne vivum ex ovo - In vivo - In vitro - In utero In Utero

In Utero is the third and final studio album from the American [i] grunge [i] ... 

- In silico
Related disciplinesMedicine Medicine

Medicine is the branch of health science [i] and the sector of public life concerned with maintaining or ... 

  - Physical anthropology - Environmental science - Life Sciences Biology

Biology is the branch of science [i] dealing with the study of life [i]. ... 

 - Biotechnology Biotechnology

Biotechnology is technology [i] based on biology [i], especially when used in agriculture [i], food science [i] ... 

Outstanding problemsOrigin of life Origin of life

In the physical sciences [i], the question of the origin of life is the study of the nature in which life [i] ... 

 - Unsolved problems in biology
OtherList of technologies - List of conservation topics

Further reading

  • Lynn Margulis Lynn Margulis

    Dr. Lynn Margulis is a biologist [i] and University Professor [i] in the Department of Geosciences [i]... 

    , Five Kingdoms: An Illustrated Guide to the Phyla of Life on Earth, 3rd ed., St. Martin's Press, 1997, paperback, ISBN 0-8050-7252-7
  • Neil Campbell, Biology , Benjamin-Cummings Publishing Company, 2004, hardcover, ISBN 0-8053-7146-X
  • Johnson George B. 2005 "Biology, Visualizing Life." Holt, Rinehart, and Winston. ISBN 0-03-016723-X





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