Biology is the study of living organisms. 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 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 energy.

The following outline is provided as an overview of and introduction to biology:

Biology portal

Essence of biology

Main article: Biology

• Anatomy
• Bio-
• Biologist
• Human anatomy
• Life
• Organism

Subdisciplines of biology

Acarology -- Anatomy -- Arachnology -- Biochemistry -- Bioinformatics -- Biomechanics -- Bionomics -- Biophysics -- Biotechnology -- Botany -- Cell biology -- Ecology -- Entomology -- Evolution -- Genetics -- Gerontology -- Herpetology -- Histology -- Ichnology -- Ichthyology -- Immunology -- Limnology -- Marine biology -- Microbiology -- Molecular biology -- Mycology -- Myrmecology -- Neurobiology -- Ornithology -- Paleontology -- Palynology -- Parasitology -- Photobiology -- Phycology -- Physiology -- Plant physiology -- Biological psychology-- Radiobiology -- Sociobiology -- Structural biology -- Taxonomy -- Virology -- Zoology

History of biology

Main article: History of biology

• Ancient Greek medicine
• Islamic medicine
• Byzantine medicine
• Medieval medicine
• History of anatomy
• History of plant systematics
• History of evolutionary thought
• History of natural history
• History of genetics
• History of model organisms
• Modern evolutionary synthesis
• History of biochemistry
• History of molecular biology
• History of biotechnology
• History of molecular evolution

Basic biology concepts

Ecology & evolution

• Life: origin of life -- Miller-Urey experiment
• Ecology:
  • Autecology: autotroph -- heterotroph -- acclimatization -- endotherm -- ectotherm -- hibernation -- homeostasis -- behavior -- circadian rhythm
  • Population ecology: population -- competition -- mating -- biological dispersal -- endemism -- niche -- growth curve -- carrying capacity
  • Community ecology: community -- keystone species -- mimicry -- symbiosis -- pollination -- mutualism -- commensalism -- parasitism -- predation -- invasive species -- environmental heterogeneity -- edge effect
  • Ecosystems: biodiversity -- biome -- habitat -- plankton -- thermocline -- carbon cycle -- water cycle -- nitrogen cycle -- food web -- trophic level -- saprobe -- decomposition
• Evolutionary biology (evolution)
  • Microevolution: species -- speciation -- adaptation -- selection -- natural selection -- directional selection -- sexual selection -- genetic drift -- sexual reproduction -- asexual reproduction -- colony -- allele frequency -- neutral theory of molecular evolution -- population genetics -- Hardy-Weinberg principle
  • Macroevolution: adaptive radiation -- convergent evolution -- extinction -- mass extinction -- fossil -- taphonomy -- geologic time -- plate tectonics -- continental drift -- vicariance -- Gondwana -- Pangaea -- endosymbiosis
  • Systematics: taxon -- taxonomy -- scientific classification -- phylogeny -- evolutionary tree -- cladistics -- synapomorphy -- homology -- molecular clock

Organismal biology

• Groups of living organisms
  • viruses : DNA viruses -- RNA viruses -- retroviruses
  • Single-cell organisms:
    • prokaryotes : microbe -- bacteria -- archaea
    • eukaryotes: fungi -- algae -- protozoa -- protista
  • Multicellular organisms:
    • plantae -- plants -- bryophytes -- pteridophytes -- seed plants
    • animalia -- animals -- metazoa -- insects -- molluscs -- vertebrates
    • fungi -- lichen -- mycorrhizae
• Developmental biology : gamete -- spermatid -- ovum -- zygote -- embryo -- cellular differentiation -- morphogenesis --homeobox
  • Animal development: stem cell -- blastula -- gastrula -- egg (biology) -- fetus -- placenta
  • Plant development: seed -- cotyledon -- meristem -- apical meristem -- vascular cambium -- cork cambium
• Morphology, Anatomy, & Physiology:
  • Techniques: electrophysiology -- electron microscopy
  • tissues -- organ -- senescence
  • Plant systems: root -- shoot -- stem -- leaf -- flower
    • vascular tissue -- Casparian strip -- turgor pressure -- xylem -- phloem -- transpiration -- wood
    • alternation of generations -- gametophyte -- antheridium -- archegonium -- sporophyte -- spore -- sporangium
    • tropism -- taxis
  • Animal systems: skin cell
    • skeleton -- bone -- cartilage -- joint -- muscle -- tendon -- actin -- myosin -- reflex
    • circulatory system -- respiration -- lung -- heart -- artery -- vein -- capillary -- blood -- blood cell
    • digestive system -- stomach -- intestine -- liver -- nutrition -- primary nutritional groups metabolism -- kidney -- excretion
    • nervous system: limbic system -- vestibular system -- neuron -- axon -- dendrite -- brain -- eye -- vision -- audition -- proprioception -- olfaction -- memory
    • nerve signaling: action potential -- signal transduction -- synapse -- receptor
    • endocrine system -- hormone
    • reproductive system -- testes -- ovary -- pregnancy
• Medicine:
  • Diseases: cancer -- diabetes -- obesity -- hereditary disease -- communicable disease
  • immune system: antibody -- host -- vaccine -- immune cell -- AIDS -- T-cell -- leucocyte
  • Drugs: antibiotic -- barbiturate -- SSRI
  • Techniques: MRI -- Computed axial tomography -- blood count

Cell & molecular biology

• Cell biology: the cell

Main article: List of basic cell biology topics

• • Techniques: cell culture -- microscope -- SEM -- TEM
  • cell components:
    • organelles: Golgi apparatus -- nucleus -- cytoplasm -- vacuole -- vesicle -- lysosome -- peroxisome -- mitochondrion -- plastid -- chloroplast
    • membranes: plasma membrane -- endomembrane system -- endoplasmic reticulum -- mitochondrial membrane -- chloroplast membrane
    • Other subcellular features: cell wall -- pseudopod -- cytoskeleton -- mitotic spindle -- flagellum -- cilium
  • cell processes:
    • diffusion -- osmosis -- isotonic -- active transport -- phagocytosis
    • energy pathways: fermentation -- glycolysis -- cellular respiration -- citric acid cycle -- photosynthesis -- Calvin cycle
    • protein biosynthesis -- ribosomes
    • cellular reproduction: cytokinesis -- centromere -- meiosis
    • nuclear reproduction: mitosis -- interphase -- prophase -- metaphase -- anaphase -- telophase
    • programmed cell death -- apoptosis -- cell senescence
• Biochemistry :
  • Biomolecules:
    • Small: amino acids -- Adenosine triphosphate (ATP) -- fats -- lipids -- oil -- phospholipid -- prion -- sugar -- vitamins -- neurotransmitter -- wax
    • Medium-sized:
      • pigments: chlorophyll -- carotenoid -- xanthophyll -- melanin
    • Biopolymers/macromolecules
      • proteins: primary structure -- secondary structure -- tertiary structure -- conformation -- native state -- protein folding -- enzyme -- receptor -- transmembrane receptor -- ion channel -- membrane transporter-- collagen -- silk
      • DNA -- RNA
      • polysaccharide: cellulose -- carbohydrate -- chitin -- glycogen -- starch
  • Biochemical mechanisms: proteolysis -- cooperativity
  • Techniques: electrophoresis -- His tag --affinity chromatography -- x-ray diffraction -- Proteomics -- mass spectrometry
• Molecular biology:
  • genetic structure: DNA -- DNA replication -- nucleosome -- genetic code -- codon -- transcription factor -- transcription -- translation -- RNA -- histone -- telomere
  • gene expression -- heterochromatin -- promoter -- enhancer -- operon
  • mutation -- point mutation -- crossover -- recombination --plasmid -- transposon
  • molecular genetics: DNA fingerprinting -- genetic fingerprint -- microsatellite -- gene knockout-- imprinting -- RNA interference
  • Genomics: computational biology -- bioinformatics
  • Molecular Techniques: gel electrophoresis -- transformation -- PCR -- PCR mutagenesis -- primer -- chromosome walking -- RFLP -- restriction enzyme -- sequencing -- shotgun sequencing -- cloning -- culture -- DNA microarray
• Genetics (classical genetics) :
  • heredity -- Mendelian inheritance -- gene -- locus -- trait -- allele -- polymorphism -- homozygote -- heterozygote -- hybrid -- hybridization -- dihybrid cross -- Punnett square
  • genotype-phenotype distinction -- genotype -- phenotype -- dominant gene -- recessive gene
  • genetic interactions -- Mendel's law of segregation -- genetic mosaic -- maternal effect -- penetrance -- complementation -- suppression -- epistasis -- genetic linkage
  • chromosomal effects: chromosome -- haploid -- diploid -- polyploidy -- dosage effect -- inbreeding
  • Model organisms: Drosophila -- Arabidopsis -- Caenorhabditis elegans -- mouse -- Saccharomyces cerevisiae -- Escherichia coli -- Lambda phage -- Xenopus
  • Techniques: genetic screen -- paternity test -- linkage map -- genetic map

Influential biologists

Main articles: Biologist and List of biologists

Charles Robert Darwin -- Alfred Russel Wallace -- Jean-Baptiste Lamarck -- Sir Charles Lyell -- Alfred Wegener -- Alexander Fleming -- Andrew Huxley -- Robert Koch -- Ernst Haeckel -- Theodor Bilharz -- Marcello Malpighi -- Antoni van Leeuwenhoek -- Konrad Lorenz -- Thomas Malthus -- Edward Jenner -- Carolus Linnaeus -- Sewall Wright -- Louis Pasteur -- Gregor Mendel -- Barbara McClintock -- James D. Watson -- Francis Crick -- Kary Mullis -- Rosalind Franklin -- Steven Jay Gould -- Lynn Margulis -- Carl Woese -- Jane Goodall -- E. O. Wilson

Biology lists

Main article: List of biology topics

• List of basic cell biology topics

See also

• Invasion biology terminology

External links

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Topic outline of biology

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At Wikiversity you can learn more about Biology at:

The School of Biology

Biology portal

• The Dolan DNA Learning Center: The source for timely information about your life
• OSU's Phylocode
• The Tree of Life: A multi-authored, distributed Internet project containing information about phylogeny and biodiversity.
• MIT video lecture series on biology
• A wiki site for protocol sharing run from MIT.
• Biology and Bioethics.
• Biology online wiki dictionary.
• Biology Video Sharing Community.

Journal links

• 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