Which one of the following statements about lipids and biological membranes is incorrect?
a) increased temperature can change the membrane from gel phase to fluid phase.
b) membrane fluidity is affected by lipid composition but not by temperature.
c) phospholipid bilayers are fluid.
d) for lipid movement, flex is faster than lateral shift.
e) ions are not allowed to freely traverse a lipid bilayer.

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.