What is the purpose of valves in the heart, in the pulmonary artery and the aorta?

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.

Of seawater increases with decrease in the temperature. therefore, the cold water sinks to the deeper layers at the bottom

The bacteria found in soil is usually harmful and measures are taken to remove any traces of microorganisms. true or false