(1) they keep toxic substances out of the cell;
(2) they contain receptors and channels that allow specific molecules, such as ions, nutrients, wastes, and metabolic products, that mediate cellular and extracellular activities to pass between organelles and between the cell and the outside environment;
(3) they separate vital but incompatible metabolic processes conducted within organelles.
<span>Diffusion and osmosis are important to cells because they don't require energy to transport very important molecules such as water and steroids.</span>
This squirrel lives in a forest and eats only acorns. <span>The squirrel will starve if it can't find enough food. </span>
<span>If each of the pairs of
chromosomes was heterozygous (what gives you the highest potential
number of different gametes), then the number of possible gametes
increases from 4 to 8 for a diploid organism. To figure out how many
are possible, raise the number of homologous chromsomes (2 for a diploid
organism) to the power of the number of chromosomes. So if you have
two different chromosomes (A and B), raise 2 to the 2nd power (or
multiply 2 x 2) and you have 4. If you have chromosomes A, B, and C,
then you have 2^3, or 2 x 2 x 2 = 8.
To show possible combinations, AaBb gives you AB, Ab, aB, or ab. AaBbCc
gives possible gametes of ABC, ABc, AbC, Abc, aBC, aBc, abC, and abc. </span>