where they execute important functions. The polypeptide chain of these proteins must cross the lipid bilayer. This presents a problem because the peptide bond is polar in nature. It turns out that in virtually all cases where an amino acid chain crosses a lipid bilayer it does so as an alpha helix. Suggest a reason why this is the case. (5 points)

What kind of action is a cause of air pollution

The pharynx is the structure in the body that serves as a pathway of both air and food. how does the body make sure that food does not get into the lungs? the salivary glands secrete enzymes that pull food out of the air pathway. the small intestine pushes the air out of the digestive system. the pancreas breaks down food in the air pathway. the epiglottis closes the air pathway so that food will not enter it.

Matthew decided he wanted to hike up mount everest. on his way to the top, it began to snow and the temperature dropped to -10°f. matthew forgot to wear a heavy jacket so his body began to shiver beyond control. in this case, matthew's body shivering is the to a drop in temperature. * 0 points reflex stimuli responce environmental facto