NationMaster - Encyclopedia: Biologic

Biology (from Greek βίος λόγος, see below) is the branch of science dealing with the study of life. It is concerned with the characteristics, classification, and behaviors of organisms, how species come into existence, and the interactions they have with each other and with the natural environment. Biology encompasses a broad spectrum of academic fields that are often viewed as independent disciplines. However, together they address phenomena related to living organisms (biological phenomena) over a wide range of scales, from biophysics to ecology. All concepts in biology are subject to the same laws that other branches of science obey, such as the laws of thermodynamics and conservation of mass. Image File history File links Portal. ... Biology (from Greek Î²Î¯Î¿Ï‚ Î»ÏŒÎ³Î¿Ï‚, see below) is the branch of science dealing with the study of life. ... Science in the broadest sense refers to any system of knowledge attained by verifiable means. ... For other uses, see Life (disambiguation), Lives (disambiguation) or Living (disambiguation), Living Things (disambiguation) Look up life, living in Wiktionary, the free dictionary. ... The word characteristic has several meanings: In mathematics, see characteristic (algebra) characteristic function characteristic subgroup Euler characteristic method of characteristics In genetics, see characteristic (genetics). ... Classification may refer to: Taxonomic classification See also class (philosophy) Statistical classification Security classification Hint: Language use may refer to a taxonomic classification that is used for statistical purposes also as a statistical classification (like International Statistical Classification of Diseases and Related Health Problems). ... Behavior or behaviour (see spelling differences) refers to the actions or reactions of an object or organism, usually in relation to the environment. ... A crab is an example of an organism. ... In biology, a species is one of the basic units of biodiversity. ... This article or section may be confusing or unclear for some readers, and should be edited to rectify this. ... Devils Punchbowl Waterfall, New Zealand. ... Basic topics | Topics | Fields | Glossaries | Lists of lists | Overviews | Portals | Tables | A-Z index | Categorical index Academic disciplines // This is a list of academic disciplines. ... A phenomenon (plural: phenomena) is an observable event, particularly something special (literally something that can be seen, derived from the Greek word phainomenon = observable). ... Biophysics (also biological physics) is an interdisciplinary science that applies the theories and methods of physical sciences, especially those of physics, to questions of biology. ... Ernst Haeckel coined the term oekologie in 1866. ... â€¹ The template below has been proposed for deletion. ... (The Lomonosov-Lavoisier law) states that the mass of a closed system of substances will remain constant, regardless of the processes acting inside the system. ...

Biology studies the variety of life (clockwise from top-left) E. coli, tree fern, gazelle, Goliath beetle

At the organism level, biology has partially explained phenomena such as birth, growth, aging, death and decay of living organisms, similarities between offspring and their parents (heredity) and flowering of plants which have puzzled humanity throughout history. Other phenomena, such as lactation, metamorphosis, egg-hatching, healing, and tropism have been addressed. On a wider scale of time and space, biologists have studied domestication of animals and plants, the wide variety of living organisms (biodiversity), changes in living organisms over many generations (evolution), extinction, speciation, social behaviour among animals, etc. Image File history File links Download high resolution version (1024x861, 165 KB)Escherichia coli: Scanning electron micrograph of Escherichia coli, grown in culture and adhered to a cover slip. ... An Australian tree fern growing on Oahu, Hawaii. ... Download high resolution version (716x864, 91 KB)Goliath Beetle Taken by fir0002 File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... PD image of gazelle from http://hawaii. ... Binomial name Escherichia coli T. Escherich, 1885 Escherichia coli (usually abbreviated to E. coli) is one of the main species of bacteria that live in the lower intestines of warm-blooded animals (including birds and mammals) and are necessary for the proper digestion of food. ... Classes Marattiopsida Osmundopsida Gleicheniopsida Pteridopsida A fern, or pteridophyte, is any one of a group of about 20,000 species of plants classified in the Division Pteridophyta, formerly known as Filicophyta. ... Species Several, see text A gazelle is an antelope of the genus Gazella. ... Suborders Adephaga Archostemata Myxophaga Polyphaga See subgroups of the order Coleoptera Wikispecies has information related to: Coleoptera Beetles are the most diverse group of insects. ... Childbirth (also called labour, birth, partus or parturition) is the culmination of a human pregnancy with the emergence of a newborn infant from its mothers uterus. ... Growth can refer to: Auxology Bacterial growth Cell growth Economic growth For financial growth due to simple interest or compound interest see Interest Exponential growth Fungal growth Logistic growth Growth hormone Personal growth Population growth Tumours can sometimes be referred to as a growth This is a disambiguation page: a... Ageing or aging is the process of getting older. ... For other uses, see Death (disambiguation). ... Rotting fruit Decomposition is a phenomenon common in the sciences of biology and chemistry. ... Heredity (the adjective is hereditary) is the transfer of characteristics from parent to offspring, either through their genes or through the social institution called inheritance (for example, a title of nobility is passed from individual to individual according to relevant customs and/or laws). ... Kittens nursing Lactation describes the secretion of milk from the mammary glands, the process of providing that milk to the young, and the period of time that a mother lactates to feed her young. ... A Pieris rapae larva An older Pieris rapae larva A Pieris rapae pupa A Pieris rapae adult Metamorphosis is a process in biology by which an individual physically develops after birth or hatching, and involves significant change in form as well as growth and differentiation. ... An average Whooping Crane egg is 102 mm long, and weighs 208 grams In some animals, an egg (Latin ovum) is the zygote, resulting from fertilization of the ovum. ... Healing is the process whereby the cells in the body regenerate and repair to reduce the size of a damaged or necrotic area. ... Phycomyces, a fungus, also exhibit phototropism A tropism is a biological phenomenon, indicating growth or turning movement of a biological organism, usually a plant, in response to an environmental stimulus. ... Domesticated animals, plants, and other organisms are those whose collective behavior, life cycle, or physiology has been altered as a result of their breeding and living conditions being under human control for multiple generations. ... Rainforests are among the most biodiverse ecosystems on earth Biodiversity or biological diversity is the diversity of life. ... A phylogenetic tree of all extant organisms, based on 16S rRNA gene sequence data, showing the evolutionary history of the three domains of life, bacteria, archaea and eukaryotes. ... In biology and ecology, extinction is the ceasing of existence of a species or group of taxa. ... Charles Darwins first sketch of an evolutionary tree from his First Notebook on Transmutation of Species (1837) Speciation is the theory of the evolutionary process by which new biological species are believed by some to arise. ... In sociology, social behaviour means a behaviour directed at other people, but one that is not designed to induce any responce. ...

While botany encompasses the study of plants, zoology is the branch of science that is concerned about the study of animals and anthropology is the branch of biology which studies human beings. However, at the molecular scale, life is studied in the disciplines of molecular biology, biochemistry, 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. At the multicellular scale, it is examined in physiology, anatomy, and histology. Developmental biology 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 organisms in their natural environment. Population genetics looks at the level of an entire population, and systematics considers the multi-species scale of lineages. Interdependent populations and their habitats are examined in ecology and evolutionary biology. A speculative new field is astrobiology (or xenobiology), which examines the possibility of life beyond the Earth. Pinguicula grandiflora Botany is the scientific study of plantlife. ... Zoology is the biological discipline which involves the study of animals. ... Anthropology (from the Greek word , human or person) consists of the study of humanity (see genus Homo). ... In chemistry, a molecule is an aggregate of at least two atoms in a definite arrangement held together by special forces. ... Molecular biology is the study of biology at a molecular level. ... This article or section does not cite its references or sources. ... Molecular genetics is the field of biology which studies the structure and function of genes at a molecular level. ... Cells in culture, stained for keratin (red) and DNA (green). ... Cell biology (also called cellular biology or cytology, from the Greek kytos, container) is an academic discipline that studies cells. ... Multicellular organisms are those organisms containing more than one cell, and having differentiated cells that perform specialized functions. ... Physiology (in Greek physis = nature and logos = word) is the study of the mechanical, physical, and biochemical functions of living organisms. ... Anatomical drawing of the human muscles from the EncyclopÃ©die. ... A thin section of lung tissue stained with hematoxylin and eosin. ... Views of a Foetus in the Womb, Leonardo da Vinci, ca. ... Ontogeny (also ontogenesis or morphogenesis) describes the origin and the development of an organism from the fertilized egg to its mature form. ... Genetics (from the Greek genno Î³ÎµÎ½Î½ÏŽ= give birth) is the science of genes, heredity, and the variation of organisms. ... Heredity (the adjective is hereditary) is the transfer of characteristics from parent to offspring, either through their genes or through the social institution called inheritance (for example, a title of nobility is passed from individual to individual according to relevant customs and/or laws). ... Ethology is the scientific study of animal behavior considered as a branch of zoology. ... Population genetics is the study of the distribution of and change in allele frequencies under the influence of the four evolutionary forces: natural selection, genetic drift, mutation, and migration. ... In biology, systematics is the study of the diversity of organism characteristics, and especially how they relate evolutionarily. ... The term lineage can refer to several things. ... Habitat (from the Latin for it inhabits) is the place where a particular species lives and grows. ... Ernst Haeckel coined the term oekologie in 1866. ... Evolutionary biology is a subfield of biology concerned with the origin and descent of species, as well as their change, multiplication, and diversity over time. ... This article or section is missing references or citation of sources. ...

1 Principles of biology
2 Scope of biology
3 History of the word "biology"
4 History
5 External links
6 See also
7 Further reading

Principles of biology

Biology does not usually describe systems in terms of objects which obey immutable physical laws described by mathematics. Biological systems have predictable statistical tendencies to behave in certain ways, but these tendencies are usually not as concrete as those described in subjects such as physics. However, biology is still subject to the same physical laws of the universe such as thermodynamics and conservation of mass. Euclid, Greek mathematician, 3rd century BC, known today as the father of geometry; shown here in a detail of The School of Athens by Raphael. ... A graph of a bell curve in a normal distribution showing statistics used in educational assessment, comparing various grading methods. ...

The biological sciences are characterized and unified by several major underlying principles and concepts: universality, evolution, diversity, continuity, genetics, homeostasis, and interactions. See also: universalism; Self-organization, Complexity General study of systems Universality is a meta-theory arguing that ostensibly discrete systems are part of a larger complex system that extends across several scales (spatially and temporally), and emerges in patterns during criticality. ... A phylogenetic tree of all extant organisms, based on 16S rRNA gene sequence data, showing the evolutionary history of the three domains of life, bacteria, archaea and eukaryotes. ... Diversity is the presence of a wide range of variation in the qualities or attributes under discussion. ... In fiction, continuity is consistency of the characteristics of persons, objects, places and events seen by the reader or viewer. ... Genetics (from the Greek genno Î³ÎµÎ½Î½ÏŽ= give birth) is the science of genes, heredity, and the variation of organisms. ... Homeostasis is the property of an open system, especially living organisms, to regulate its internal environment to maintain a stable, constant condition, by means of multiple dynamic equilibrium adjustments, controlled by interrelated regulation mechanisms. ... Generally, an interaction is a kind of action which occurs as two or more objects have an effect upon one another. ...

Universality: Biochemistry, cells, and the genetic code

Schematic representation of DNA, the primary genetic material.

Main article: Life

Some striking examples of biological universality include life's carbon-based biochemistry and its ability to pass on characteristics via genetic material, using a DNA and RNA based genetic code with only minor variations across all living things. Image File history File links DNA-structure-and-bases. ... Image File history File links DNA-structure-and-bases. ... The general structure of a section of DNA Deoxyribonucleic acid (DNA) is a nucleic acid that contains the genetic instructions for the biological development of a cellular form of life or a virus. ... Genetic material is the material used to store genetic information for a living organism. ... For other uses, see Life (disambiguation), Lives (disambiguation) or Living (disambiguation), Living Things (disambiguation) Look up life, living in Wiktionary, the free dictionary. ... General Name, Symbol, Number carbon, C, 6 Chemical series nonmetals Group, Period, Block 14, 2, p Appearance black (graphite) colorless (diamond) Atomic mass 12. ... Biology studies the variety of life (clockwise from top-left) E. coli, tree fern, gazelle, Goliath beetle Biology is the science of life (from the Greek words bios = life and logos = reasoned account). ... This article or section does not cite its references or sources. ... Heredity (the adjective is hereditary) is the transfer of characteristics from parent to offspring, either through their genes or through the social institution called inheritance (for example, a title of nobility is passed from individual to individual according to relevant customs and/or laws). ... Genetic material is the material used to store genetic information for a living organism. ... RNA codons. ...

Another universal principle is that all organisms (that is, all forms of life on Earth except for viruses) are made of cells. Similarly, all organisms share common developmental processes. A crab is an example of an organism. ... Groups I: dsDNA viruses II: ssDNA viruses III: dsRNA viruses IV: (+)ssRNA viruses V: (-)ssRNA viruses VI: ssRNA-RT viruses VII: dsDNA-RT viruses A virus (Latin, poison) is a microscopic particle that can infect the cells of a biological organism. ... Cells in culture, stained for keratin (red) and DNA (green). ...

Evolution: The central principle of biology

Main article: Evolution

The central organizing concept in biology is that all life has a common origin and has changed and developed through the process of evolution (see Common descent). This has led to the striking similarity of units and processes discussed in the previous section. Charles Darwin established evolution as a viable theory by articulating its driving force, natural selection (Alfred Russel Wallace is recognized as the co-discoverer of this concept). Genetic drift was embraced as an additional mechanism of evolutionary development in the modern synthesis of the theory. A phylogenetic tree of all extant organisms, based on 16S rRNA gene sequence data, showing the evolutionary history of the three domains of life, bacteria, archaea and eukaryotes. ... A phylogenetic tree of all extant organisms, based on 16S rRNA gene sequence data, showing the evolutionary history of the three domains of life, bacteria, archaea and eukaryotes. ... A group of organisms is said to have common descent if they have a common ancestor. ... Charles Robert Darwin FRS (12 February 1809 â€“ 19 April 1882) was an English naturalist who achieved lasting fame by producing considerable evidence that species originated through evolutionary change, at the same time proposing the scientific theory that natural selection is the mechanism by which such change occurs. ... Natural selection is the process by which individual organisms with favorable traits are more likely to survive and reproduce. ... Alfred Russel Wallace for the Cornish painter see Alfred Wallis Alfred Russel Wallace, OM , FRS (January 8, 1823 â€“ November 7, 1913) was a British naturalist, geographer, anthropologist and biologist. ... Genetic drift is the term used in population genetics to refer to the statistical drift over time of allele frequencies in a finite population due to random sampling effects in the formation of successive generations. ... The modern evolutionary synthesis (often referred to simply as the modern synthesis), neo-Darwinian synthesis or neo-Darwinism, brings together Charles Darwins theory of the evolution of species by natural selection with Gregor Mendels theory of genetics as the basis for biological inheritance. ...

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 sequences conducted within molecular biology or genomics, and comparisons of fossils or other records of ancient organisms in paleontology. Biologists organize and analyze evolutionary relationships through various methods, including phylogenetics, phenetics, and cladistics (The major events in the evolution of life, as biologists currently understand them, are summarized on this evolutionary timeline).
In biology, a species is one of the basic units of biodiversity. ... In biology, phylogenetics (Greek: phylon = tribe, race and genetikos = relative to birth, from genesis = birth) is the study of evolutionary relatedness among various groups of organisms (e. ... part of a DNA sequence A DNA sequence (sometimes genetic sequence) is a succession of letters representing the primary structure of a real or hypothetical DNA molecule or strand, The possible letters are A, C, G, and T, representing the four nucleotide subunits of a DNA strand (adenine, cytosine, guanine... Molecular biology is the study of biology at a molecular level. ... Genomics is the study of an organisms genome and the use of the genes. ... An ammonite fossil Fossils (from Latin fossus, literally having been dug up) are the mineralized or otherwise preserved remains or traces (such as footprints) of animals, plants, and other organisms. ... A paleontologist carefully chips rock from a column of dinosaur vertebrae. ... In biology, phylogenetics (Greek: phylon = tribe, race and genetikos = relative to birth, from genesis = birth) is the study of evolutionary relatedness among various groups of organisms (e. ... In biology, phenetics, also known as numerical taxonomy, is an attempt to classify organisms based on overall similarity, usually in morphology or other observable traits, regardless of their phylogeny or evolutionary relation. ... This cladogram shows the relationship among various insect groups. ... This timeline outlines the major events in the development of life on planet Earth. ...

Diversity: The variety of living organisms

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A phylogenetic tree of all living things, based on rRNA gene data, showing the separation of the three domains bacteria, archaea, and eukaryotes as described initially by Carl Woese. Trees constructed with other genes are generally similar, although they may place some early-branching groups very differently, presumably owing to rapid rRNA evolution. The exact relationships of the three domains are still being debated.

The evolutionary trees (phylogenetic trees) of the organism being classified. Classification is the province of the disciplines of systematics and taxonomy. 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 and genetics, shifting the focus from physical similarities and shared characteristics to phylogenetics. Image File history File links Phylogenetic_tree. ... Image File history File links Phylogenetic_tree. ... It has been suggested that Evolutionary tree be merged into this article or section. ... The evolutionary tree of living things is currently supposed to run something along the lines of that listed below. ... A non-coding RNA (ncRNA) is any RNA molecule that functions without being translated into a protein. ... This stylistic schematic diagram shows a gene in relation to the double helix structure of DNA and to a chromosome (right). ... Phyla/Divisions Actinobacteria Aquificae Bacteroidetes/Chlorobi Chlamydiae/Verrucomicrobia Chloroflexi Chrysiogenetes Cyanobacteria Deferribacteres Deinococcus-Thermus Dictyoglomi Fibrobacteres/Acidobacteria Firmicutes Fusobacteria Gemmatimonadetes Nitrospirae Omnibacteria Planctomycetes Proteobacteria Spirochaetes Thermodesulfobacteria Thermomicrobia Thermotogae Bacteria (singular, bacterium) are a major group of living organisms. ... Phyla / Classes Phylum Crenarchaeota Phylum Euryarchaeota Halobacteria Methanobacteria Methanococci Methanopyri Archaeoglobi Thermoplasmata Thermococci Phylum Korarchaeota Phylum Nanoarchaeota Archaea (; from Greek Î±ÏÏ‡Î±Î¯Î±, old ones; singular Archaeum, Archaean, or Archaeon), also called Archaebacteria (), is a major division of living organisms. ... Kingdoms Animalia - Animals Fungi Plantae - Plants Protista A eukaryote is an organism with a complex cell or cells, in which the genetic material is organized into a membrane-bound nucleus or nuclei. ... Carl Richard Woese (born July 15, 1928) is an American microbiologist famous for defining the Archaea (a new domain or kingdom of life) in 1976 by phylogenetic analysis of 16S ribosomal RNA, a technique pioneered by Woese and which is now standard practice. ... It has been suggested that Evolutionary tree be merged into this article or section. ... In biology, systematics is the study of the diversity of organism characteristics, and especially how they relate evolutionarily. ... Taxonomy, sometimes alpha taxonomy, is the science of finding, describing and naming organisms, thus giving rise to taxa. ... A taxon (plural taxa) is an element of a taxonomy, e. ... This cladogram shows the relationship among various insect groups. ... Genetics (from the Greek genno Î³ÎµÎ½Î½ÏŽ= give birth) is the science of genes, heredity, and the variation of organisms. ... In biology, phylogenetics (Greek: phylon = tribe, race and genetikos = relative to birth, from genesis = birth) is the study of evolutionary relatedness among various groups of organisms (e. ...

Traditionally, living things have been divided into five kingdoms:

Monera -- Protista -- Fungi -- Plantae -- Animalia

However, many scientists now consider this five-kingdom system to be outdated. Modern alternative classification systems generally begin with the three-domain system: A phylogenetic tree of living things, based on rRNA sequence data, showing the separation of bacteria, archaea, and eukaryotes. ... Typical phyla Protists (IPA: ) are a heterogeneous group of living things, comprising those eukaryotes that are not animals, plants, or fungi. ... Divisions Chytridiomycota Zygomycota Glomeromycota Ascomycota Basidiomycota Deuteromycota A fungus (plural fungi) is a eukaryotic organism that digests its food externally and absorbs the nutrient molecules into its cells. ... Divisions Green algae Chlorophyta Charophyta Land plants (embryophytes) Non-vascular plants (bryophytes) Marchantiophyta - liverworts Anthocerotophyta - hornworts Bryophyta - mosses Vascular plants (tracheophytes) â€ Rhyniophyta - rhyniophytes â€ Zosterophyllophyta - zosterophylls Lycopodiophyta - clubmosses â€ Trimerophytophyta - trimerophytes Equisetophyta - horsetails Pteridophyta - true ferns Psilotophyta - whisk ferns Ophioglossophyta - adderstongues Seed plants (spermatophytes) â€ Pteridospermatophyta - seed ferns Pinophyta - conifers Cycadophyta - cycads Ginkgophyta... Phyla Subregnum Parazoa Porifera (sponges) Subregnum Agnotozoa Placozoa (trichoplax) Orthonectida (orthonectids) Rhombozoa (dicyemids) Subregnum Eumetazoa Radiata (unranked) (radial symmetry) Ctenophora (comb jellies) Cnidaria (coral, jellyfish, anemones) Bilateria (unranked) (bilateral symmetry) Acoelomorpha (basal) Myxozoa (slime animals) Superphylum Deuterostomia (blastopore becomes anus) Chordata (vertebrates, etc. ... The three-domain system is a biological classification introduced by Carl Woese in 1990 that emphasizes his separation of prokaryotes into two groups, originally called Eubacteria and Archaebacteria. ...

Archaea (originally Archaebacteria) -- Bacteria (originally Eubacteria) -- Eukaryota

These domains reflect whether the cells have nuclei or not, as well as differences in the cell exteriors. Phyla / Classes Phylum Crenarchaeota Phylum Euryarchaeota Halobacteria Methanobacteria Methanococci Methanopyri Archaeoglobi Thermoplasmata Thermococci Phylum Korarchaeota Phylum Nanoarchaeota Archaea (; from Greek Î±ÏÏ‡Î±Î¯Î±, old ones; singular Archaeum, Archaean, or Archaeon), also called Archaebacteria (), is a major division of living organisms. ... Phyla/Divisions Actinobacteria Aquificae Bacteroidetes/Chlorobi Chlamydiae/Verrucomicrobia Chloroflexi Chrysiogenetes Cyanobacteria Deferribacteres Deinococcus-Thermus Dictyoglomi Fibrobacteres/Acidobacteria Firmicutes Fusobacteria Gemmatimonadetes Nitrospirae Omnibacteria Planctomycetes Proteobacteria Spirochaetes Thermodesulfobacteria Thermomicrobia Thermotogae Bacteria (singular, bacterium) are a major group of living organisms. ... Kingdoms Animalia - Animals Fungi Plantae - Plants Protista A eukaryote is an organism with a complex cell or cells, in which the genetic material is organized into a membrane-bound nucleus or nuclei. ...

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 activity: A parasite is an organism that spends a significant portion of its life in or on the living tissue of a host organism and which causes harm to the host without immediately killing it. ... Metabolism (from Greek Î¼ÎµÏ„Î±Î²Î¿Î»Î¹ÏƒÎ¼ÏŒÏ‚ metabolismos) is the biochemical modification of chemical compounds in living organisms and cells. ...

Viruses -- Viroids -- Prions

A common alternate meaning of virus is computer virus. ... Families Pospiviroidae Avsunviroidae Viroids are plant pathogens that consist of a short stretch (a few hundred bases) of highly complementary, circular, single-stranded RNA without the protein coat that is typical for viruses. ... A prion (IPA: [1] ) â€” short for proteinaceous infectious particle â€” (by analogy to virion) is a type of infectious agent. ...

Continuity: The common descent of life

Main article: Common descent

Up into the 19th century, it was commonly believed that life forms could appear spontaneously under certain conditions (see abiogenesis). This misconception was challenged by William Harvey's diction that "all life [is] from [an] egg" (from the Latin "Omne vivum ex ovo"), 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 have common descent if they have a common ancestor. ... Alternative meaning: Nineteenth Century (periodical) (18th century — 19th century — 20th century — more centuries) As a means of recording the passage of time, the 19th century was that century which lasted from 1801-1900 in the sense of the Gregorian calendar. ... Abiogenesis (Greek a-bio-genesis, non biological origins) is, in its most general sense, the generation of life from non-living matter. ... William Harvey (April 1, 1578â€“June 3, 1657) was a medical doctor who is credited with first correctly describing, in exact detail, the properties of blood being pumped around the body by the heart. ... Latin is an ancient Indo-European language originally spoken in Latium, the region immediately surrounding Rome. ... Omne vivum ex ovo is Latin for All live [is] from [an] egg. This is a foundational concept of modern biology. ...

A group of organisms is said to share a common descent if they share a common ancestor. All organisms on the Earth 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. Biologists generally regard the universality of the genetic code as definitive evidence in favor of the theory of universal common descent (UCD) for all bacteria, archaea, and eukaryotes (see: origin of life). An ancestor is a parent or (recursively) the parent of an ancestor (i. ... A crab is an example of an organism. ... Earth (IPA: , often referred to as the Earth, Terra, or Planet Earth) is the third planet in the solar system in terms of distance from the Sun, and the fifth largest. ... The gene pool of a species or a population is the complete set of unique alleles that would be found by inspecting the genetic material of every living member of that species or population. ... This timeline of the evolution of life outlines the major events in the development of life on the planet Earth. ... RNA codons. ... Phyla/Divisions Actinobacteria Aquificae Bacteroidetes/Chlorobi Chlamydiae/Verrucomicrobia Chloroflexi Chrysiogenetes Cyanobacteria Deferribacteres Deinococcus-Thermus Dictyoglomi Fibrobacteres/Acidobacteria Firmicutes Fusobacteria Gemmatimonadetes Nitrospirae Omnibacteria Planctomycetes Proteobacteria Spirochaetes Thermodesulfobacteria Thermomicrobia Thermotogae Bacteria (singular, bacterium) are a major group of living organisms. ... Phyla / Classes Phylum Crenarchaeota Phylum Euryarchaeota Halobacteria Methanobacteria Methanococci Methanopyri Archaeoglobi Thermoplasmata Thermococci Phylum Korarchaeota Phylum Nanoarchaeota Archaea (; from Greek Î±ÏÏ‡Î±Î¯Î±, old ones; singular Archaeum, Archaean, or Archaeon), also called Archaebacteria (), is a major division of living organisms. ... Kingdoms Animalia - Animals Fungi Plantae - Plants Protista A eukaryote is an organism with a complex cell or cells, in which the genetic material is organized into a membrane-bound nucleus or nuclei. ... Pre-Cambrian stromatolites in the Siyeh Formation, Glacier National Park. ...

Homeostasis: Adapting to change

Main article: Homeostasis

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 organisms, whether unicellular or multicellular, exhibit homeostasis. Homeostasis manifests itself at the cellular level through the maintenance of a stable internal acidity (pH); at the organismic level, warm-blooded animals maintain a constant internal body temperature; and at the level of the ecosystem, as when atmospheric carbon dioxide levels rise and plants are theoretically able to grow healthier and remove more of the gas from the atmosphere. Tissues and organs can also maintain homeostasis. Homeostasis is the property of an open system, especially living organisms, to regulate its internal environment to maintain a stable, constant condition, by means of multiple dynamic equilibrium adjustments, controlled by interrelated regulation mechanisms. ... An open system may refer to more than one thing: In computing, an open system (computing) is a computer operating system that provides interoperability, portability or both, particularly Unix systems. ... A dynamic equilibrium will form if, at a given temperature, two reversible processes occur at the same rate. ... A crab is an example of an organism. ... A microorganism or microbe is an organism that is so small that it is microscopic (invisible to the naked eye). ... Multicellular organisms are those organisms containing more than one cell, and having differentiated cells that perform specialized functions. ... pH is a measure of the acidity of a solution in terms of activity of hydrogen ions (H+). For dilute solutions, however, it is convenient to substitute the activity of the hydrogen ions with the molarity (mol/L) of the hydrogen ions (however, this is not necessarily accurate at higher... A warm-blooded (homeothermic) animal is one that can keep its core body temperature at a nearly constant level regardless of the temperature of the surrounding environment (that is, to maintain thermal homeostasis) . This can involve not only the ability to generate heat, but also the ability to cool down... An ecosystem, a contraction of ecological and system, refers to the collection of components and processes that comprise, and govern the behavior of, some defined subset of the biosphere. ... Carbon dioxide is a chemical compound composed of one carbon and two oxygen atoms. ... Divisions Green algae Chlorophyta Charophyta Land plants (embryophytes) Non-vascular plants (bryophytes) Marchantiophyta - liverworts Anthocerotophyta - hornworts Bryophyta - mosses Vascular plants (tracheophytes) â€ Rhyniophyta - rhyniophytes â€ Zosterophyllophyta - zosterophylls Lycopodiophyta - clubmosses â€ Trimerophytophyta - trimerophytes Equisetophyta - horsetails Pteridophyta - true ferns Psilotophyta - whisk ferns Ophioglossophyta - adderstongues Seed plants (spermatophytes) â€ Pteridospermatophyta - seed ferns Pinophyta - conifers Cycadophyta - cycads Ginkgophyta... Biological tissue is a collection of interconnected cells that perform a similar function within an organism. ... In biology, an organ is a group of tissues which perform some function. ...

Interactions: Groups and environments

Mutual symbiosis between clownfish of the genus Amphiprion that dwell among the tentacles of tropical sea anemones. The territorial fish protects the anemone from anemone-eating fish, and in turn the stinging tentacles of the anemone protects the clown fish from its predators

Every living thing interacts with other organisms and its environment. 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 responding to a local sugar gradient is responding to its environment as much as a lion is responding to its environment when it searches for food in the African savannah. For any given species, behaviors can be co-operative, aggressive, parasitic or symbiotic. Matters become more complex when two or more different species interact in an ecosystem. Studies of this type are the province of ecology. Common Clownfish (Amphiprion ocellaris) in their Magnificent Sea Anemone (Heteractis magnifica) home. ... Common Clownfish (Amphiprion ocellaris) in their Magnificent Sea Anemone (Heteractis magnifica) home. ... Common Clownfish (Amphiprion ocellaris) in their Magnificent sea anemone (Heteractis magnifica) home. ... Species Twenty-seven, including: Amphiprion allardi - Allards Clownfish Amphiprion melanopus - Cinnamon Clownfish Amphiprion clarkii - Clarks Anemonefish Amphiprion ocellaris - Ocellaris Clownfish Amphiprion percula - Percula Clownfish Amphiprion perideraion - Pink Skunk Clownfish Amphiprion polymnus - Saddleback Clownfish Amphiprion sebae - Sebae Clownfish Amphiprion tricinctus - Three-Band Anemonefish Amphiprion ephippium - Red Saddleback Anemonefish Amphiprion... Species Twenty-seven, including: Amphiprion allardi - Allards Clownfish Amphiprion melanopus - Cinnamon Clownfish Amphiprion clarkii - Clarks Anemonefish Amphiprion ocellaris - Ocellaris Clownfish Amphiprion percula - Percula Clownfish Amphiprion perideraion - Pink Skunk Clownfish Amphiprion polymnus - Saddleback Clownfish Amphiprion sebae - Sebae Clownfish Amphiprion tricinctus - Three-Band Anemonefish Amphiprion ephippium - Tomato Clownfish Amphiprion frenatus... Families Many, see text. ... Phyla/Divisions Actinobacteria Aquificae Bacteroidetes/Chlorobi Chlamydiae/Verrucomicrobia Chloroflexi Chrysiogenetes Cyanobacteria Deferribacteres Deinococcus-Thermus Dictyoglomi Fibrobacteres/Acidobacteria Firmicutes Fusobacteria Gemmatimonadetes Nitrospirae Omnibacteria Planctomycetes Proteobacteria Spirochaetes Thermodesulfobacteria Thermomicrobia Thermotogae Bacteria (singular, bacterium) are a major group of living organisms. ... To meet Wikipedias quality standards, this article or section may require cleanup. ... A world map showing the continent of Africa. ... A savanna or savannah is a grassland with widely spaced trees, and occurs in several types of biomes. ... Behavior or behaviour (see spelling differences) refers to the actions or reactions of an object or organism, usually in relation to the environment. ... Co-operation refers to the practice of people or greater entities working in common with commonly agreed-upon goals and possibly methods, instead of working separately in competition. ... To meet Wikipedias quality standards and make it easier to understand, this article or section may require cleanup. ... A parasite is an organism that spends a significant portion of its life in or on the living tissue of a host organism and which causes harm to the host without immediately killing it. ... Common Clownfish (Amphiprion ocellaris) in their Magnificent sea anemone (Heteractis magnifica) home. ... An ecosystem, a contraction of ecological and system, refers to the collection of components and processes that comprise, and govern the behavior of, some defined subset of the biosphere. ... Ernst Haeckel coined the term oekologie in 1866. ...

Scope of biology

Main article: List of biology disciplines

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, genes 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 sequences, which assist in understanding the genetic variation of a population; and physiology borrows extensively from cell biology in describing the function of organ systems.
This is a list of biology disciplines. ... Cells in culture, stained for keratin (red) and DNA (green). ... This stylistic schematic diagram shows a gene in relation to the double helix structure of DNA and to a chromosome (right). ... part of a DNA sequence A DNA sequence (sometimes genetic sequence) is a succession of letters representing the primary structure of a real or hypothetical DNA molecule or strand, The possible letters are A, C, G, and T, representing the four nucleotide subunits of a DNA strand (adenine, cytosine, guanine...

Structure of life

Schematic of typical animal cell depicting the various organelles and structures

Main articles: Molecular biology, Cell biology, Genetics, and Developmental biology

Molecular biology is the study of biology at a molecular level. This field overlaps with other areas of biology, particularly with genetics and biochemistry. 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. Image File history File links Biological_cell. ... Image File history File links Biological_cell. ... Cells in culture, stained for keratin (red) and DNA (green). ... Schematic of typical animal cell, showing subcellular components. ... Molecular biology is the study of biology at a molecular level. ... Cell biology (also called cellular biology or cytology, from the Greek kytos, container) is an academic discipline that studies cells. ... Genetics (from the Greek genno Î³ÎµÎ½Î½ÏŽ= give birth) is the science of genes, heredity, and the variation of organisms. ... Views of a Foetus in the Womb, Leonardo da Vinci, ca. ... Molecular biology is the study of biology at a molecular level. ... In science, a molecule is the smallest particle of a pure chemical substance that still retains its chemical composition and properties. ... Genetics (from the Greek genno Î³ÎµÎ½Î½ÏŽ= give birth) is the science of genes, heredity, and the variation of organisms. ... This article or section does not cite its references or sources. ...

Cell biology studies the physiological properties of cells, as well as their behaviors, interactions, and environment. This is done both on a microscopic and molecular level. Cell biology researches both single-celled organisms like bacteria and specialized cells in multicellular organisms like humans. Cell biology (also called cellular biology or cytology, from the Greek kytos, container) is an academic discipline that studies cells. ... Physiology (in Greek physis = nature and logos = word) is the study of the mechanical, physical, and biochemical functions of living organisms. ... Cells in culture, stained for keratin (red) and DNA (green). ... Behavior or behaviour (see spelling differences) refers to the actions or reactions of an object or organism, usually in relation to the environment. ... A microscope (Greek: micron = small and scopos = aim) is an instrument for viewing objects that are too small to be seen by the naked or unaided eye. ... In chemistry, a molecule is an aggregate of at least two atoms in a definite arrangement held together by special forces. ... Phyla/Divisions Actinobacteria Aquificae Bacteroidetes/Chlorobi Chlamydiae/Verrucomicrobia Chloroflexi Chrysiogenetes Cyanobacteria Deferribacteres Deinococcus-Thermus Dictyoglomi Fibrobacteres/Acidobacteria Firmicutes Fusobacteria Gemmatimonadetes Nitrospirae Omnibacteria Planctomycetes Proteobacteria Spirochaetes Thermodesulfobacteria Thermomicrobia Thermotogae Bacteria (singular, bacterium) are a major group of living organisms. ... Trinomial name Homo sapiens sapiens Linnaeus, 1758 Humans, or human beings, are bipedal primates belonging to the mammalian species Homo sapiens (Latin for wise man or knowing man) under the family Hominidae (known as the great apes). ...

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 of genes, heredity, and the variation of organisms. In modern research, genetics provides important tools in the investigation of the function of a particular gene, or the analysis of genetic interactions. Within organisms, genetic information generally is carried in chromosomes, where it is represented in the chemical structure of particular DNA molecules. Genetics (from the Greek genno Î³ÎµÎ½Î½ÏŽ= give birth) is the science of genes, heredity, and the variation of organisms. ... Science in the broadest sense refers to any system of knowledge attained by verifiable means. ... This stylistic schematic diagram shows a gene in relation to the double helix structure of DNA and to a chromosome (right). ... Heredity (the adjective is hereditary) is the transfer of characteristics from parent to offspring, either through their genes or through the social institution called inheritance (for example, a title of nobility is passed from individual to individual according to relevant customs and/or laws). ... In music, variation is a formal technique where material is altered during repetition; reiteration with changes. ... A crab is an example of an organism. ... Genetic interactions, in genetics, are interactions that occur between two or more mutations that results in a new phenotype. ... A crab is an example of an organism. ... Figure 1: Chromosome. ... part of a DNA sequence A DNA sequence (sometimes genetic sequence) is a succession of letters representing the primary structure of a real or hypothetical DNA molecule or strand, The possible letters are A, C, G, and T, representing the four nucleotide subunits of a DNA strand (adenine, cytosine, guanine... The general structure of a section of DNA Deoxyribonucleic acid (DNA) is a nucleic acid that contains the genetic instructions for the biological development of a cellular form of life or a virus. ... In chemistry, a molecule is an aggregate of at least two atoms in a definite arrangement held together by special forces. ...

Genes encode the information necessary for synthesizing proteins, which in turn play a large role in influencing (though, in many instances, not completely determining) the final phenotype of the organism. This stylistic schematic diagram shows a gene in relation to the double helix structure of DNA and to a chromosome (right). ... The phenotype of an individual organism is either its total physical appearance and constitution or a specific manifestation of a trait, such as size, eye color, or behavior that varies between individuals. ...

Developmental biology studies the process by which organisms grow and develop. Originating in embryology, modern developmental biology studies the genetic control of cell growth, differentiation, and "morphogenesis," which is the process that gives rise to tissues, organs, and anatomy. Model organisms for developmental biology include the round worm Caenorhabditis elegans, the fruit fly Drosophila melanogaster, the zebrafish Brachydanio rerio, the mouse Mus musculus, and the weed Arabidopsis thaliana. Embryology is the branch of developmental biology that studies embryos and their development. ... The term cell growth is used in two different ways in biology. ... Embryonic stem cells differentiate into cells in various body organs. ... Morphogenesis is also the name of a band. ... Biological tissue is a collection of interconnected cells that perform a similar function within an organism. ... In biology, an organ (Latin: organum, instrument, tool) is a group of tissues that perform a specific function or group of functions. ... Anatomical drawing of the human muscles from the EncyclopÃ©die. ... A model organism is a species that is extensively studied to understand particular biological phenomena, with the expectation that discoveries made in the organism model will provide insight into the workings of other organisms. ... Binomial name Caenorhabditis elegans Maupas, 1900 Caenorhabditis elegans (pronounced see-no-rab-DYE-tis) is a free-living nematode (one of the roundworms), about 1 mm in length, which lives in a temperate soil environment. ... Binomial name Drosophila melanogaster Meigen, 1830 Drosophila melanogaster (from the Greek for black-bellied dew-lover) is a dipteran (two-winged) insect, and is the species of fruit fly that is most commonly used in genetic experiments; it is among the most important model organisms. ... Binomial name Danio rerio (Hamilton-Buchanan, 1822) The Zebra Danio or Zebrafish (Brachydanio rerio or Danio rerio) is a tropical fish belonging to the minnow family (Cyprinidae). ... Binomial name Mus musculus Linnaeus, 1758 Mus musculus is the common house mouse. ... Binomial name Arabidopsis thaliana (L.) Heynh. ...

Physiology of organisms

Main articles: Physiology, Anatomy Physiology (in Greek physis = nature and logos = word) is the study of the mechanical, physical, and biochemical functions of living organisms. ... Anatomical drawing of the human muscles from the EncyclopÃ©die. ...

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 is being studied. For example, what is learned about the physiology of yeast cells can also apply to human cells. The field of animal physiology extends the tools and methods of human physiology to non-human species. Plant physiology also borrows techniques from both fields. In botany, plant physiology is the study of the function, or physiology, of plants. ... Physiology (in Greek physis = nature and logos = word) is the study of the mechanical, physical, and biochemical functions of living organisms. ... A crab is an example of an organism. ... Diagram of a yeast cell Yeasts are single-celled (unicellular) fungi, a few species of which are commonly used to leaven bread, ferment alcoholic beverages, and even drive experimental fuel cells. ... Trinomial name Homo sapiens sapiens Linnaeus, 1758 Humans, or human beings, are bipedal primates belonging to the mammalian species Homo sapiens (Latin for wise man or knowing man) under the family Hominidae (known as the great apes). ... Human physiology is the science of the mechanical, physical, and biochemical functions of normal humans or human tissues or organs. ... In biology, a species is one of the basic units of biodiversity. ...

Anatomy is an important branch of physiology and considers how organ systems in animals, such as the nervous, immune, endocrine, respiratory, and circulatory systems, function and interact. The study of these systems is shared with medically oriented disciplines such as neurology and immunology. Anatomical drawing of the human muscles from the EncyclopÃ©die. ... In biology, an organ is a group of tissues which perform some function. ... The nervous system of an animal coordinates the activity of the muscles, monitors the organs, constructs and also stops input from the senses, and initiates actions. ... The immune system is composed of a complex constellation of cells, organs and tissues, arranged in an elaborate and dynamic communications network and equipped to optimize the response against invasion by pathogenic organisms. ... This article or section does not cite its references or sources. ... The Respiratory System The respiratory system is an organ system which is used for gas exchange. ... Human circulatory system. ... Medicine is the branch of health science and the sector of public life concerned with maintaining or restoring human health through the study, diagnosis, treatment and possible prevention of disease and injury. ... Neurology is a branch of medicine dealing with disorders of the nervous system. ... Immunology is a broad branch of biomedical science that covers the study of all aspects of the immune system in all organisms. ...

Diversity and evolution of organisms

In population genetics the evolution of a population of organisms is sometimes depicted as if travelling on a fitness landscape. The arrows indicate the preferred flow of a population on the landscape, and the points A, B, and C are local optima. The red ball indicates a population that moves from a very low fitness value to the top of a peak

Main articles: Evolutionary biology, Biodiversity, Botany, Zoology Importing fitness landscape cartoon image originally included in Nupedia fitness landscape article-in-progress (originally titled fig1. ... Importing fitness landscape cartoon image originally included in Nupedia fitness landscape article-in-progress (originally titled fig1. ... Population genetics is the study of the distribution of and change in allele frequencies under the influence of the four evolutionary forces: natural selection, genetic drift, mutation, and migration. ... A phylogenetic tree of all extant organisms, based on 16S rRNA gene sequence data, showing the evolutionary history of the three domains of life, bacteria, archaea and eukaryotes. ... In evolutionary biology, fitness landscapes or adaptive landscapes are used to visualize the relationship between genotypes (or phenotypes) and replicatory success. ... Evolutionary biology is a subfield of biology concerned with the origin and descent of species, as well as their change, multiplication, and diversity over time. ... Rainforests are among the most biodiverse ecosystems on earth Biodiversity or biological diversity is the diversity of life. ... Pinguicula grandiflora Botany is the scientific study of plantlife. ... Zoology is the biological discipline which involves the study of animals. ...

Evolutionary biology is concerned with the origin and descent of species, as well as their change over time, and includes scientists from many taxonomically-oriented disciplines. For example, it generally involves scientists who have special training in particular organisms 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, which uses the fossil 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, developmental biology 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. In biology, a species is one of the basic units of biodiversity. ... Taxonomy, sometimes alpha taxonomy, is the science of finding, describing and naming organisms, thus giving rise to taxa. ... A crab is an example of an organism. ... In biology, mammalogy is the study of mammals, a class of vertebrates with characteristics such as homeothermic metabolism, fur, four-chambered hearts, and complex nervous systems. ... This article or section is in need of attention from an expert on the subject. ... Herpetology (Greek herpeton = to creep, to ramp and logos = in this context explanation or reason) is the branch of zoology concerned with the study of reptiles and amphibians. ... A paleontologist carefully chips rock from a column of dinosaur vertebrae. ... An ammonite fossil Fossils (from Latin fossus, literally having been dug up) are the mineralized or otherwise preserved remains or traces (such as footprints) of animals, plants, and other organisms. ... Population genetics is the study of the distribution of and change in allele frequencies under the influence of the four evolutionary forces: natural selection, genetic drift, mutation, and migration. ... See also 1990s, the band The 1990s decade refers to the years from 1990 to 1999, inclusive, sometimes informally including popular culture from the very late 1980s and from 2000 and beyond. ... Views of a Foetus in the Womb, Leonardo da Vinci, ca. ... Evolutionary developmental biology (evolution of development or informally, evo-devo) is a field of biology that compares the developmental processes of different animals in an attempt to determine the ancestral relationship between organisms and how developmental processes evolved. ... In biology, phylogenetics (Greek: phylon = tribe, race and genetikos = relative to birth, from genesis = birth) is the study of evolutionary relatedness among various groups of organisms (e. ... In biology, systematics is the study of the diversity of organism characteristics, and especially how they relate evolutionarily. ... Taxonomy, sometimes alpha taxonomy, is the science of finding, describing and naming organisms, thus giving rise to taxa. ...

The two major traditional taxonomically-oriented disciplines are botany and zoology. Botany is the scientific study of plants. Botany covers a wide range of scientific disciplines that study the growth, reproduction, metabolism, development, diseases, and evolution of plant life. Zoology involves the study of animals, including the study of their physiology within the fields of anatomy and embryology. The common genetic and developmental mechanisms of animals and plants is studied in molecular biology, molecular genetics, and developmental biology. The ecology of animals is covered under behavioral ecology and other fields. Pinguicula grandiflora Botany is the scientific study of plantlife. ... Zoology is the biological discipline which involves the study of animals. ... Divisions Green algae Chlorophyta Charophyta Land plants (embryophytes) Non-vascular plants (bryophytes) Marchantiophyta - liverworts Anthocerotophyta - hornworts Bryophyta - mosses Vascular plants (tracheophytes) â€ Rhyniophyta - rhyniophytes â€ Zosterophyllophyta - zosterophylls Lycopodiophyta - clubmosses â€ Trimerophytophyta - trimerophytes Equisetophyta - horsetails Pteridophyta - true ferns Psilotophyta - whisk ferns Ophioglossophyta - adderstongues Seed plants (spermatophytes) â€ Pteridospermatophyta - seed ferns Pinophyta - conifers Cycadophyta - cycads Ginkgophyta... Growth can refer to: Auxology Bacterial growth Cell growth Economic growth For financial growth due to simple interest or compound interest see Interest Exponential growth Fungal growth Logistic growth Growth hormone Personal growth Population growth Tumours can sometimes be referred to as a growth This is a disambiguation page: a... For other uses, see Reproduction (disambiguation) Reproduction is the biological process by which new individual organisms are produced. ... Metabolism (from Greek Î¼ÎµÏ„Î±Î²Î¿Î»Î¹ÏƒÎ¼ÏŒÏ‚ metabolismos) is the biochemical modification of chemical compounds in living organisms and cells. ... Morphogenesis is also the name of a band. ... Phytopathology or Plant Pathology is the science of diagnosing and managing plant diseases. ... A phylogenetic tree of all extant organisms, based on 16S rRNA gene sequence data, showing the evolutionary history of the three domains of life, bacteria, archaea and eukaryotes. ... Phyla Subregnum Parazoa Porifera (sponges) Subregnum Agnotozoa Placozoa (trichoplax) Orthonectida (orthonectids) Rhombozoa (dicyemids) Subregnum Eumetazoa Radiata (unranked) (radial symmetry) Ctenophora (comb jellies) Cnidaria (coral, jellyfish, anemones) Bilateria (unranked) (bilateral symmetry) Acoelomorpha (basal) Myxozoa (slime animals) Superphylum Deuterostomia (blastopore becomes anus) Chordata (vertebrates, etc. ... Physiology (in Greek physis = nature and logos = word) is the study of the mechanical, physical, and biochemical functions of living organisms. ... Anatomical drawing of the human muscles from the EncyclopÃ©die. ... Embryology is the branch of developmental biology that studies embryos and their development. ... Genetics (from the Greek genno Î³ÎµÎ½Î½ÏŽ= give birth) is the science of genes, heredity, and the variation of organisms. ... Molecular biology is the study of biology at a molecular level. ... Molecular genetics is the field of biology which studies the structure and function of genes at a molecular level. ... Views of a Foetus in the Womb, Leonardo da Vinci, ca. ... Ernst Haeckel coined the term oekologie in 1866. ... Behavioral ecology is the study of the ecological and evolutionary basis for animal behavior, and the roles of behavior in enabling an animal to adapt to its environment (both intrinsic and extrinsic). ...

Classification of life

The dominant classification system is called Linnaean taxonomy, which includes ranks and binomial nomenclature. How organisms are named is governed by international agreements such as the International Code of Botanical Nomenclature (ICBN), the International Code of Zoological Nomenclature (ICZN), and the International Code of Nomenclature of Bacteria (ICNB). 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 (ICVCN) remains outside the BioCode. Linnaean taxonomy classifies living things into a hierarchy, originally starting with kingdoms. ... In biology, binomial nomenclature is the formal method of naming species. ... The International Code of Botanical Nomenclature (ICBN) is the set of rules that governs plant nomenclature, i. ... The International Code of Zoological Nomenclature (ICZN) is a set of rules in zoology that have one fundamental aim: to provide the maximum universality and continuity in classifying all animals according to taxonomic judgment. ... The International Code of Nomenclature of Bacteria governs the scientific names for bacteria. ... Viruses can be classified in several ways, such as by their geometry, by whether they have envelopes, by the identity of the host organism they can infect, by mode of transmission, or by the type of disease they cause. ...

Interactions of organisms

A food web, a generalization of the food chain, depicting the complex interrelationships among organisms in an ecosystem.

Main articles: Ecology, Ethology, Behavior, Biogeography An example of a foodweb diagram; drawn myself. ... Figure 1. ... An ecosystem, a contraction of ecological and system, refers to the collection of components and processes that comprise, and govern the behavior of, some defined subset of the biosphere. ... Ernst Haeckel coined the term oekologie in 1866. ... Ethology is the scientific study of animal behavior considered as a branch of zoology. ... Behavior or behaviour (see spelling differences) refers to the actions or reactions of an object or organism, usually in relation to the environment. ... Biogeography is the science which deals with patterns of species distribution and the processes that result in such patterns. ...

Ecology studies the distribution and abundance of living organisms, and the interactions between organisms and their environment. The environment of an organism includes both its habitat, which can be described as the sum of local abiotic factors such as climate and geology, as well as the other the organisms that share its habitat. Ecological systems are studied at several different levels, from individuals and populations to ecosystems and the biosphere. As can be surmised, ecology is a science that draws on several disciplines. Ernst Haeckel coined the term oekologie in 1866. ... For other uses, see Life (disambiguation), Lives (disambiguation) or Living (disambiguation), Living Things (disambiguation) Look up life, living in Wiktionary, the free dictionary. ... The Blue Marble: The famous photo of the Earth taken en route to the Moon by Apollo 17s Harrison Schmitt on December 7, 1972. ... An ecosystem, a contraction of ecological and system, refers to the collection of components and processes that comprise, and govern the behavior of, some defined subset of the biosphere. ... The biosphere is the part of a planets outer shell â€” including air, land, surface rocks and water â€” within which life occurs, and which biotic processes in turn alter or transform. ...

Ethology studies animal behavior (particularly of social animals such as primates and canids), and is sometimes considered a branch of zoology. Ethologists have been particularly concerned with the evolution of behavior and the understanding of behavior in terms of the theory of natural selection. In one sense, the first modern ethologist was Charles Darwin, whose book The expression of the emotions in animals and men influenced many ethologists. Ethology is the scientific study of animal behavior considered as a branch of zoology. ... Phyla Subregnum Parazoa Porifera (sponges) Subregnum Agnotozoa Placozoa (trichoplax) Orthonectida (orthonectids) Rhombozoa (dicyemids) Subregnum Eumetazoa Radiata (unranked) (radial symmetry) Ctenophora (comb jellies) Cnidaria (coral, jellyfish, anemones) Bilateria (unranked) (bilateral symmetry) Acoelomorpha (basal) Myxozoa (slime animals) Superphylum Deuterostomia (blastopore becomes anus) Chordata (vertebrates, etc. ... Behavior or behaviour (see spelling differences) refers to the actions or reactions of an object or organism, usually in relation to the environment. ... Families 15, See classification A primate (L. prima, first) is any member of the biological order Primates, the group that contains all the species commonly related to the lemurs, monkeys, and apes, with the latter category including humans. ... Genera Alopex Atelocynus Canis Cerdocyon Chrysocyon Cuon Dusicyon Fennecus Lycalopex Lycaon Nyctereutes Otocyon Pseudalopex Speothos Urocyon Vulpes Canidae is the family of carnivorous and omnivorous mammals commonly known as canines. ... Zoology is the biological discipline which involves the study of animals. ... A phylogenetic tree of all extant organisms, based on 16S rRNA gene sequence data, showing the evolutionary history of the three domains of life, bacteria, archaea and eukaryotes. ... Natural selection is the process by which individual organisms with favorable traits are more likely to survive and reproduce. ... Charles Robert Darwin FRS (12 February 1809 â€“ 19 April 1882) was an English naturalist who achieved lasting fame by producing considerable evidence that species originated through evolutionary change, at the same time proposing the scientific theory that natural selection is the mechanism by which such change occurs. ...

Biogeography studies the spatial distribution of organisms on the Earth, focusing on topics like plate tectonics, climate change, dispersal and migration, and cladistics. Biogeography is the science which deals with patterns of species distribution and the processes that result in such patterns. ... Earth (IPA: , often referred to as the Earth, Terra, or Planet Earth) is the third planet in the solar system in terms of distance from the Sun, and the fifth largest. ... This article or section does not cite its references or sources. ... Variations in CO2, temperature and dust from the Vostok ice core over the last 400 000 years Climate change refers to the variation in the Earths global climate or in regional climates over time. ... This cladogram shows the relationship among various insect groups. ...

History of the word "biology"

Formed by combining the Greek βίος (bios), meaning 'life', and λόγος (logos), meaning 'study of', the word "biology" in its modern sense seems to have been introduced independently by Gottfried Reinhold Treviranus (Biologie oder Philosophie der lebenden Natur, 1802) and by Jean-Baptiste Lamarck (Hydrogéologie, 1802). 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. Gottfried Reinhold Treviranus (February 4, 1776 - February 16, 1837) was a German naturalist. ... --69. ... Jean-Baptiste Lamarck Jean-Baptiste Pierre Antoine de Monet, Chevalier de Lamarck (August 1, 1744 â€“ December 28, 1829) was a French naturalist and an early proponent of the idea that evolution occurred and proceeded in accordance with natural laws. ... 1800 (MDCCC) was an exceptional common year starting on Wednesday of the Gregorian calendar, but a leap year starting on Sunday of the Julian calendar. ... 1766 was a common year starting on Wednesday (see link for calendar). ...

History

Main articles: History of biology, History of medicine, and History of genetics

Major discoveries in biology include: The history of biology dates as far back as the rise of various civilization as classic philosophers did their own ways of biology as a system of understanding life. ... All human societies have medical beliefs that provide explanations for, and responses to, birth, death, and disease. ... Gregor Mendel, the father of genetics The history of genetics is generally held to have started in 1865 when an Austrian monk, Gregor Mendel published his work on pea plants. ...

Cell theory is a scientific theory that is one of the foundations of biology. ... The germ theory of disease, also called the pathogenic theory of medicine, is a theory that proposes that microorganisms are the cause of many diseases. ... Genetics (from the Greek genno Î³ÎµÎ½Î½ÏŽ= give birth) is the science of genes, heredity, and the variation of organisms. ... A phylogenetic tree of all extant organisms, based on 16S rRNA gene sequence data, showing the evolutionary history of the three domains of life, bacteria, archaea and eukaryotes. ... The general structure of a section of DNA Deoxyribonucleic acid (DNA) is a nucleic acid that contains the genetic instructions for the biological development of a cellular form of life or a virus. ...

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MIT video lecture series on biology
The Vega Science Trust Hours of Freeview Science Video.

Journal Links Image File history File links Wikibooks-logo-en. ... Wikibooks logo Wikibooks, previously called Wikimedia Free Textbook Project and Wikimedia-Textbooks, is part of the Wikimedia Foundation. ... Wikipedia does not have an article with this exact name. ... Wiktionary is a Wikimedia Foundation project intended to be a free wiki dictionary (hence: Wiktionary) (including thesaurus and lexicon) in every language. ... Image File history File links Wikiversity_beta. ... Wikiversity is a Wikimedia Foundation project, hosted in Wikibooks. ... Types of Clade (Note: Stem-based is now branch-based, to avoid confusion with the term stem group which means total clade minus crown clade.) The PhyloCode is a developing draft for a formal set of rules governing phylogenetic nomenclature. ...

PLos Biology A peer-reviewed, open-access journal published by the Public Library of Science
International Journal of Biological Sciences A biological journal publishes peer-reviewed scientific papers of significance
Perspectives in Biology and Medicine

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