During prometaphase, the microtubules of the mitotic spindle attach only to the kinetochore of a single sister chromatid and not to the other for the maternal copy of chromosome 21. what will happen to the copy number of chromosome 21 in the resulting daughter cells?

a. one of the daughter cells is missing both copies of chromosome 21 and the other cell has four copies of chromosome 21.

b. both daughter cells have double the normal number of chromosome 21 (four copies each).

c. one of the daughter cells has trisomy (three copies) of chromosome 21 and the other daughter cell is missing one of the two copies of chromosome 21.

Place the steps tor the formation of the enzyme pepsinogen in correct order

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).

What is responsible for the uneven heating between the poles and the equator on any given day