ecology- topic 12

• food webs are a series of interlinking food chains
• producers are the base of all trophic levels+ food chains, usually use light energy from the sun to produce food. autotrophs- organisms make their own food
• predator organisms which hunt and kill other organisms, apex predators does not get hunted
• consumers are organisms which consume other organisms, herbivores, carnivores and omnivores
• pyramid of energy, only about 10 percent of energy is passed between levels
• decomposers break down all trophic levels and return them to nutrients to be absorbed by plants again. decomposers do not hunt the consumers, they just break them down after they have died
• abiotic factors affect population size, light intensity, temperature, moisture levels, soil PH, wind intensity
• abiotic tolerance graph every species is able to survive within a range of these factors, some species have a wide range other have a narrow range
• biotic factors affect population size, avaliability of food, new predators, new pathogen, competition
• saprotrophic nutrition is the digestion of dead food material outside the body, using extracellular enzymes as conducted by fungi
• habitat is a place where organism live
• biodiversity is the variety of how many different species, and how many organisms of each species are present in an ecosystem
• nice is a role that an organism plays within the community of an ecosystem
• symbiosis close relationship between two different species where both benefit
• parasitism is relationship between parasite and his host, parasite benefits by gaining energy from host, host harmed by loosing energy, parasites limited metabolism cannot survive out of contact with host
• biomass is measure in g/m2, can also be measure in no of organisms, height of bars is important
• pros and cons of using quadrants, it is quicker then counting each individual organisms, may not accurately represent the total population if densely or not densely populations areas are not included
• community all of the organisms present in an ecosystem
• population is all the organisms of one species found in a particular habitat
• carrying capacity is the maximum population size of a particular species that a given ecosystem can sustain
• trophic levels are tertiary consumers, secondary consumer, primary consumers, producer
• pyramids of biomass, have a larger base, have a pyramid shape
• ecosystem all the living organisms (biotic factors) and the non living components (abiotic factors) within the habitat
• using quadrats in a random location, count the number of x in the quadrat, repeat 3x for accuracy and caudate mean
• not all energy is transferred as excreted in urine, decomposition of organism, not all the organism is eaten