Skin color in humans is an example of a phenotypic trait that is determined by polygenic inheritance. three separate gene loci determine skin color (p, q and r), where each gene locus has an additive effect on skin color and the capital letters represent incompletely dominant alleles producing dark skin. what fraction of the children of a medium-toned (ppqqrr) mother and medium-toned (ppqqrr) father would exhibit the lightest possible skin color(genotype: ppqqrr)?

The endoplasmic reticulum (er) is an organelle in some cells. in these cells, it is continuous with the nuclear membrane and forms a large part of the cell\'s total membrane. sort the phrases below as describing rough er, smooth er, both, or neither. note: if you answer any part of this question incorrectly, a single red x will appear indicating that one or more of the phrases are sorted incorrectly.1) found in prokaryites and uekaryotys2) involved in protein synthesis3) involve in lipid synthesis4) contains molecular chaperones in lumen5) bound with ribosomes6) involved in toxin or drug metabolism7) large systemot internnected tubules,vesicles, and sacs8) "packages" enzymes in vesicles for secretion.

List the advantages and disadavantages of the switch from persistent chlorinated hydrocarbon pesticides (such as ddt) to nonpersistent organophosphate pesicides. have the benefits of the switch outweighed the disadvantages? explain.

Is there any species that went extinct in recent years due to natural causes (not caused by human interaction). if so, what caused it?