Carbohydrates Practice Test

A storage polysaccharide in animal cells is composed of glucose monomers with frequent $b1$-1,6 branch points off an $b1$-1,4 backbone. The branches create many nonreducing ends where enzymes can bind simultaneously, increasing the rate at which glucose units can be removed from the polymer. Which feature best explains why branching increases the number of enzyme-accessible ends?

Chitin is a structural polysaccharide composed of repeating N-acetylglucosamine monomers linked by $b2(1\to4)$ glycosidic bonds. The acetamide (N-acetyl) group on each monomer can participate in hydrogen bonding with neighboring chains, allowing many parallel chains to pack tightly. An arthropod exoskeleton sample made largely of chitin is hard and resists deformation. Which molecular feature best explains this rigidity?

Which feature best explains chitinbcs high rigidity compared with many storage polysaccharides?