Answer:
C. Sometimes molecules need to move from low to high concentrations.
Explanation:
Answer:
glutamic acid, because the R group could form ionic bonds
arginine, because the R group could form ionic bonds
tryptophan and tyrosine, because the R groups are small, allowing close stacking
glycine and alanine, because the R groups are small, allowing close stacking
Sebaceous glands shrink in size :) hope that's you out