Which practice fits the definition of conservation? a. throwing away a paper towel after cleaning a countertop. b. cleaning a countertop with a sponge and rinsing it out to reuse. c. throwing away a soda can after finishing the soda. d. using a disposable plastic bag to carry groceries and then throwing it out.

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).

At which point is crust neither created nor destroyed? island chain mid-ocean ridge divergent boundary transform boundary

The term facultative anaerobe refers to an organism that