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/ˌsimbēˈōsis/  /-bī-/ Noun, pl. symbioses 1. Close and often long-term interaction between two or more different biological species. In 1877, Bennett used the word symbiosis (which previously had been used to depict people living together in community) to describe the mutualistic relationship in lichens. In 1879, the German mycologist Heinrich Anton de Bary defined it as “the living together of unlike organisms.” The definition of symbiosis is controversial among scientists. Some believe symbiosis should only refer to persistent mutualisms, while others believe it should apply to any types of persistent biological interactions (i.e. mutualistic, commensalistic, or parasitic). ( 2. A close, prolonged association between two or more organisms of different species that normally benefits both members. ( 3. The relationship between two different species of organisms that are interdependent; each gains benefits from the other. A relationship between different species where both of the organisms in question benefit from the presence of the other. ( 4. The living together in more or less intimate association or close union of two dissimilar organisms (as in parasitism or commensalism); especially mutualism. ( Word origin: From Modern Latin, from Greek symbiosis “a living together,” from symbioun “live together,” from symbios “(one) living together (with another), partner,” from syn- “together” + bios...

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/ˈsimitrē/ Noun 1. In biology, the repetition of the parts in an animal or plant in an orderly fashion. Specifically, symmetry refers to a correspondence of body parts, in size, shape, and relative position, on opposite sides of a dividing line or distributed around a central point or axis. With the exception of radial symmetry, external form has little relation to internal anatomy, since animals of very different anatomical construction may have the same type of symmetry. ( 2. In biology, is the balanced distribution of duplicate body parts or shapes. In nature and biology, symmetry is approximate. For example, plant leaves, while considered symmetric, rarely match up exactly when folded in half. Symmetry creates a class of patterns in nature, where the near-repetition of the pattern element is by reflection or rotation. ( 3. Exact correspondence on either side of a dividing line, plane, center or axis. ( 4. The satisfying arrangement of a balanced distribution of the elements of a whole. ( 5. A due proportion of the several parts of a body to each other; adaptation of the form or dimensions of the several parts of a thing to each other; the union and conformity of the members of a work to the whole. ( 5. In biology, the law of likeness; similarity of structure; regularity in form and arrangement; orderly and similar distribution of parts,...

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