Which of the following events is not an example of diffusion?
a. while still some distance away, the smell of apples from a nearby fruit stall becomes very evident.
b. a person pouring water from a pitcher into a glass to get a drink
c. the exchange of oxygen and carbon dioxide in the lungs’ air sacs as a person respires.
d. a blue copper (ii) sulfate crystal dissolves slowly when placed in a beaker of water without stirring, giving a uniformly light blue solution.

In this case, the statement that people who exercise for an hour may have lower cholesterol levels is .

Melting glaciers is a serious threat to the environment what is the possible consequence of melting glaciers on polar bears?

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).