BIOLOGY AND ECOLOGY QUESTIONS

Biology and Ecology Questions



Biology and Ecology Questions

Mutualism

Mutual aid is a term used in a number of areas of life including biology, social relations, economics, and politics. It refers to help that is given by one party to another. The party may be nonhuman or it may be human. In the case of humans, it is usually aid given according to prior agreements. In biology, mutual aid is termed mutualism. It describes the mutual benefit and the interactions that take place between two or more species. The mutualism between two species can be lifelong contact that is physical or chemical. If the mutualism between them is lifelong, it is referred to as symbiosis. (Bond 1994)

Clown fish live in symbiotic relationship with sea anemones. On the other hand, pollinators such as bees that interact with flowering plants have a non-symbiotic relationship. Politically, mutual aid has been a principle idea of anarchism and libertarian socialism. Pierre-Joseph Proudhon was a French anarchist and an advocate of mutualism. Russian Prince Peter Kropotkin advocated the development of mutual aid societies. He believed that government was the cause of all social ills. The solution was the abolition of all government. In his anarchistic “state of nature” people would voluntarily join together for mutual benefits and then would trade their products for those of other people in other groups. Kropotkin's vision of a system of voluntary associations that would create an economy where mutual exchanges took place was described in his book The Conquest of Bread. He was influenced in his thinking by Darwin's theory of evolution and by the development of mutualism in biology. (Burgess 1998)

Food Web

Food webs are portrayals of the feeding relationships that exist amidst species within an ecosystem, indicating flows of energy and biomass between trophic levels. Although a food web is a more complex conception than a linear food chain, it remains a relatively static and binary depiction: species either interact or they don't. Despite these limitations, food webs are useful conceptual tools, providing insights into the organization of communities and the interactions among different species within them. (Caldwell 1998)

Food webs are organized into trophic (or feeding) levels. Species are categorized as either producers or consumers. Producers or autotrophs, literally “selffeeders,” constitute the first trophic level—those species that synthesize their own food through processes of photosynthesis or chemosynthesis and includes most plants, algae, phytoplankton, and some species of bacteria. Photosynthetic species use carbon dioxide, water, and the light energy of the sun to produce sugar molecules as well as oxygen. Thus, these species are responsible for producing the relatively oxygen-rich atmosphere that exists on earth today. Chemosynthetic species produce carbohydrates via several different possible chemical pathways. Some use the chemical energy bound up in inorganic molecules (such as hydrogen sulfide), to produce carbohydrates from carbon (derived from carbon dioxide or methane), and oxygen. (Dawson 1993)

Consumers, also termed heterotrophs, feed on other organisms, both living as well as dead. Those that eat the latter are decomposers or detritus ...