Make a list of eight products in your immediate surroundings that are derived from organisms. (examples: cotton pants, leather watch band, wool scarf, paper, wooden furniture, piece of candy, rubber eraser, and wicker basket).

choose one of the products and answer the following questions regarding the organism that the product is derived from (reasonable guesses or speculation is ok):

what is the organism?
where does the organism live?
briefly characterize the ecosystem that the organism lives in.
provide one example of how the organism depends on another organism.
what are some threats to the organism in the ecosystem?
speculate on how your life would be affected if the organism became extinct.

Which phrase is the best summary of the model shown? a. the transfer of the sun's energy through trophic levels b. a series of aerobic and anaerobic reactions c. a transformation of light energy into chemical energy d. the breakdown of food molecules

The kidney filters potentially toxic substances in the blood, and thus “clears” the blood of those substances. this clearance function is dependent upon and proportional to the diffusion gradient of the substance across filtering capillaries, i.e. if the concentration of the substance is doubled, twice as much will be cleared from each ml of blood that is filtered. suppose that the body produces a constant amount of a substance x per unit of time. the kidneys eliminate substance x at a rate directly proportional to the concentration of the substance and the volume of blood cleared each minute (c): elimination = c × [x], where [x] is the steady-state concentration of substance x. imagine an individual with an initial concentration of x equal to [x]0 who develops kidney disease. her baseline clearance c0 drops to one half of the original (½c0). what is the new steady state concentration of x? (for simplicity, assume that substance x is 100% filtered by the kidney).

How does secondary succession differ from primary succession?