Friday, May 9, 2008
Fri-Day 1
Bio- we saw more examples of environmental ABIOTIC (non-living) factors. We then defined CARRYING CAPACITY of an environment as the maximum number (capacity) of members of a given POPULATION that an environment can "carry"/support. The FINITE or limited quantity of abiotic factors in an environment directly determines the carrying capacity of, for example, polar bears in their environment. The other determinants of carrying capacity are the BIOTIC factors i.e. the other populations that make up the community, their actions, their wastes, etc.
We looked at the types of nutritional relationships that are possible in an ecosystem. AUTOTROPHS merely require inorganic abiotic factors (like CO2 and H2O) and an energy source (sunlight) to make carbohydrates and other important macromolecules; autotrophs make their own nutrition. Plants and algae are the main autotrophs on Earth. HETEROTROPHS depend on other organisms as sources of their nutrition. There are four main categories of heterotrophs: carnivores (meat-eaters), herbivores (plant eaters), omnivores, and saprophytes (live off of dead plants and animals).
We also discussed possible SYMBIOTIC relationships between pairs of populations in a community:
commensalism: +, o (win-draw)
mutualism: +, + (win-win)
parasitism: +, - (win-lose)
We then finished our peppered-moth lab discussion and continued working on our finch-beak selection lab.
We looked at the types of nutritional relationships that are possible in an ecosystem. AUTOTROPHS merely require inorganic abiotic factors (like CO2 and H2O) and an energy source (sunlight) to make carbohydrates and other important macromolecules; autotrophs make their own nutrition. Plants and algae are the main autotrophs on Earth. HETEROTROPHS depend on other organisms as sources of their nutrition. There are four main categories of heterotrophs: carnivores (meat-eaters), herbivores (plant eaters), omnivores, and saprophytes (live off of dead plants and animals).
We also discussed possible SYMBIOTIC relationships between pairs of populations in a community:
commensalism: +, o (win-draw)
mutualism: +, + (win-win)
parasitism: +, - (win-lose)
We then finished our peppered-moth lab discussion and continued working on our finch-beak selection lab.
# posted by C @ 12:11 PM 
