Some people can roll the tongue into a tube shape, while others cannot. Practicing is not likely to help because tongue-rolling is an inherited trait. The allele for rolling the tongue (R) is dominant to the allele for not being able to roll the tongue (r). Create a Punnett square. Make sure that it shows a cross between two parents with at least one R allele.

An easy way to calculate the amount of energy available at each level is to what?

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).

18. how do the cells in meiosis differ from the cells in mitosis?