Which state looks like it has an area shaped like the heel of a boot?

According to the diagram, what sources contribute to the phosphorus found in soil? according to the diagram, phosphorus found in soil contributes phosphorus to what other sources? (site 1)

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.

Why do leaves change color in the fall? green pigments break down and no longer mask the color of chlorophyll. chlorophyll breaks down and no longer masks the colors of other pigments. red- and yellow-colored pigments grow and mask green-colored chlorophyll. green-colored chlorophyll breaks down and turns red and yellow.