HOME
*





Isomorph
An isomorph is an organism that does not change in shape during growth. The implication is that its volume is proportional to its cubed length, and its surface area to its squared length. This holds for any shape it might have; the actual shape determines the proportionality constants. The reason why the concept is important in the context of the Dynamic Energy Budget (DEB) theory is that food ( substrate) uptake is proportional to surface area, and maintenance to volume. Since volume grows faster than surface area, this controls the ultimate size of the organism. Alfred Russel Wallace wrote this in a letter to E. B. Poulton in 1865.see Finch, C. 1990 ''Longevity, senescence, and the genome'' Univ Chicago Press Appendix 3 The surface area that is of importance is the part that is involved in substrate uptake (e.g. the gut surface), which is typically a fixed fraction of the total surface area in an isomorph. The DEB theory explains why isomorphs grow according to the von Bertalan ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Shape Correction Function
The shape correction function is a ratio of the surface area of a growing organism and that of an isomorph as function of the volume. The shape of the isomorph is taken to be equal to that of the organism for a given reference volume, so for that particular volume the surface areas are also equal and the shape correction function has value one. For a volume V and reference volume V_d, the shape correction function M(V) equals: * V0-morphs: M(V) = (V/V_d)^ * V1-morphs: M(V) = (V/V_d)^ * Isomorphs: M(V) = (V/V_d)^0 = 1 Static mixtures between a V0 and a V1-morph can be found as: M(V) = w(V/V_d)^ + (1-w)(V/V_d)^ for 0 The shape correction function is used in Dynamic Energy Budget theory to correct equations for isomorphs to organisms that change shape during growth. The conversion is necessary for accurately modelling food (substrate) acquisition and mobilization of reserve for use by metabolism.


References

{{DEFAULTSORT:Shape Correction Function Deve ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Dynamic Energy Budget
The dynamic energy budget (DEB) theory is a formal metabolic theory which provides a single quantitative framework to dynamically describe the aspects of metabolism (energy and mass budgets) of all living organisms at the individual level, based on assumptions about energy uptake, storage, and utilization of various substances. The DEB theory adheres to stringent thermodynamic principles, is motivated by universally observed patterns, is non-species specific, and links different levels of biological organization (cells, organisms, and populations) as prescribed by the implications of energetics. Models based on the DEB theory have been successfully applied to over a 1000 species with real-life applications ranging from conservation, aquaculture, general ecology, and ecotoxicology (see also thAdd-my-pet collection. The theory is contributing to the theoretical underpinning of the emerging field of metabolic ecology. The explicitness of the assumptions and the resulting predictions e ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Substrate (biology)
In biology, a substrate is the surface on which an organism (such as a plant, fungus, or animal) lives. A substrate can include biotic or abiotic materials and animals. For example, encrusting algae that lives on a rock (its substrate) can be itself a substrate for an animal that lives on top of the algae. Inert substrates are used as growing support materials in the hydroponic cultivation of plants. In biology substrates are often activated by the nanoscopic process of substrate presentation. In agriculture and horticulture * Cellulose substrate * Expanded clay aggregate (LECA) * Rock wool * Potting soil * Soil In animal biotechnology Requirements for animal cell and tissue culture Requirements for animal cell and tissue culture are the same as described for plant cell, tissue and organ culture (In Vitro Culture Techniques: The Biotechnological Principles). Desirable requirements are (i) air conditioning of a room, (ii) hot room with temperature recorder, (iii) microscope r ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Alfred Russel Wallace
Alfred Russel Wallace (8 January 1823 – 7 November 1913) was a British naturalist, explorer, geographer, anthropologist, biologist and illustrator. He is best known for independently conceiving the theory of evolution through natural selection. His 1858 paper on the subject was published that year alongside extracts from Charles Darwin's earlier writings on the topic. It spurred Darwin to set aside the "big species book" he was drafting, and quickly write an abstract of it, published in 1859 as ''On the Origin of Species''. Wallace did extensive fieldwork, first in the Amazon River basin. He then did fieldwork in the Malay Archipelago, where he identified the faunal divide now termed the Wallace Line, which separates the Indonesian archipelago into two distinct parts: a western portion in which the animals are largely of Asian origin, and an eastern portion where the fauna reflect Australasia. He was considered the 19th century's leading expert on the geographical di ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Edward Bagnall Poulton
Sir Edward Bagnall Poulton, FRS HFRSE FLS (27 January 1856 – 20 November 1943) was a British evolutionary biologist, a lifelong advocate of natural selection through a period in which many scientists such as Reginald Punnett doubted its importance. He invented the term sympatric for evolution of species in the same place, and in his book ''The Colours of Animals'' (1890) was the first to recognise frequency-dependent selection. Poulton is also remembered for his pioneering work on animal coloration. He is credited with inventing the term aposematism for warning coloration, as well as for his experiments on 'protective coloration' (camouflage). Poulton became Hope Professor of Zoology at the University of Oxford in 1893. Life Edward Poulton was born in Reading, Berkshire on 27 January 1856 the son of the architect William Ford Poulton and his wife, Georgina Sabrina Bagnall. He was educated at Oakley House School in Reading. Between 1873 and 1876, Poulton studied at Jesu ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  




Von Bertalanffy
Karl Ludwig von Bertalanffy (19 September 1901 – 12 June 1972) was an Austrian biologist known as one of the founders of general systems theory (GST). This is an interdisciplinary practice that describes systems with interacting components, applicable to biology, cybernetics and other fields. Bertalanffy proposed that the classical laws of thermodynamics might be applied to closed systems, but not necessarily to "open systems" such as living things. His mathematical model of an organism's growth over time, published in 1934, is still in use today. Bertalanffy grew up in Austria and subsequently worked in Vienna, London, Canada, and the United States. Biography Ludwig von Bertalanffy was born and grew up in the little village of Atzgersdorf (now Liesing) near Vienna. The Bertalanffy family had roots in the 16th century nobility of Hungary which included several scholars and court officials.T.E. Weckowicz (1989). Ludwig von Bertalanffy (1901-1972): A Pioneer of General Systems ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


V0-morph
A V0-morph is an organism whose surface area remains constant as the organism grows. The reason why the concept is important in the context of the Dynamic Energy Budget theory is that food (substrate) uptake is proportional to surface area, and maintenance to volume. The surface area that is of importance is that part that is involved in substrate uptake. Biofilms on a flat solid substrate are examples of V0-morphs; they grow in thickness, but not in surface area that is involved in nutrient exchange. Other examples are dinophyta and diatoms that have a cell wall that does not change during the cell cycle. During cell-growth, when the amounts of protein and carbohydrates increase, the vacuole shrinks. The outer membrane that is involved in nutrient uptake remains constant. At cell division, the daughter cells rapidly take up water, complete a new cell wall and the cycle repeats. Rods (bacteria that have the shape of a rod and grow in length, but not in diameter) are a static mixtu ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


V1-morph
An V1-morph is an organism that changes in shape during growth such that its surface area is proportional to its volume. In most cases both volume and surface area are proportional to length The reason the concept is important in the context of the Dynamic Energy Budget theory is that food (substrate) uptake is proportional to surface area, and maintenance to volume. The surface area that is of importance is that part that is involved in substrate uptake. Since uptake is proportional to maintenance for V1-morphs, there is no size control, and an organism grows exponentially at constant food (substrate) availability. Filaments, such as fungi that form hyphae growing in length, but not in diameter, are examples of V1-morphs. Sheets that extend, but do not change in thickness, like some colonial bacteria and algae, are another example. An important property of V1-morphs is that the distinction between the individual and the population level disappears; a single long filament grows as ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Dynamic Energy Budget
The dynamic energy budget (DEB) theory is a formal metabolic theory which provides a single quantitative framework to dynamically describe the aspects of metabolism (energy and mass budgets) of all living organisms at the individual level, based on assumptions about energy uptake, storage, and utilization of various substances. The DEB theory adheres to stringent thermodynamic principles, is motivated by universally observed patterns, is non-species specific, and links different levels of biological organization (cells, organisms, and populations) as prescribed by the implications of energetics. Models based on the DEB theory have been successfully applied to over a 1000 species with real-life applications ranging from conservation, aquaculture, general ecology, and ecotoxicology (see also thAdd-my-pet collection. The theory is contributing to the theoretical underpinning of the emerging field of metabolic ecology. The explicitness of the assumptions and the resulting predictions e ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]