World Library  
Flag as Inappropriate
Email this Article

Function (biology)

Article Id: WHEBN0010013669
Reproduction Date:

Title: Function (biology)  
Author: World Heritage Encyclopedia
Language: English
Subject: Protein–DNA interaction, CASP, Anatomical terminology, Skeleton, Flowering plant
Collection:
Publisher: World Heritage Encyclopedia
Publication
Date:
 

Function (biology)

Space-filling model of the chlorophyll molecule, which is involved in photosynthesis.

A biological function is the reason some object or process occurred in a system that evolved through a process of selection or natural selection. Thus, function refers forward from the object or process, along some chain of causation, to the goal or success.[1] Compare this to the mechanism of the object or process, which looks backward along some chain of causation, explaining how the feature occurred.

A functional characteristic is known as an Spandrel (biology)). They may also have a reduced function or lost function entirely over time due to changing conditions, in which case they are said to be vestigial.

The correlation of form (also referred to as structure) and function is one of the central themes in biology. However, knowing the structure of something does not necessarily reveal its function. To illustrate the point, an enzymologist discovering an unknown enzyme would be highly unlikely to identify its function with only structural information. It is also possible for different structures to carry out the same function. Teeth and the gizzard of a bird highlight this point: both grind up food, serving the same function in terms of digestion.

As another example, the function of chlorophyll in a plant is to capture the energy of sunlight for photosynthesis, which contributes to growth and reproduction, and reproduction contributes to evolutionary success. Taking a broader view, all functions have the same end in that they contribute to fitness, though they are each manifested through various proximate mechanisms.

Function is not the same as purpose in the teleological sense. Evolution is a blind process which has no 'goal' for the future. For example, a tree does not grow flowers for any purpose, but does so simply because it has evolved to do so. To say 'a tree grows flowers to attract pollinators' would be incorrect if the 'to' implies purpose. A function describes what something does, not what its 'purpose' is. However, teleological terminology is often used by biologists as a sort of shorthand way of describing function, even though they know it is technically incorrect.

As applied to ecosystems, the word 'function' has quite a different meaning, and is basically a synonym for processes. Ecosystems do not reproduce and thus cannot be said to have any function in the above sense.

The word may also for non-biological entities, e.g. the ozone layer might be said to have the 'function' of blocking ultraviolet radiation, though this use of the word also does not necessarily imply any teleological cause.

See also

Notes and references

  1. ^ Dusenbery, David B. (1992). Sensory Ecology, pp.7-8. W.H. Freeman., New York. ISBN 0-7167-2333-6.
This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and USA.gov, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for USA.gov and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
 
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
 
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.
 


Copyright © World Library Foundation. All rights reserved. eBooks from Project Gutenberg are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.