These structures can undergo stress relaxation and an extension called creep that is catalyzed by   expansins.
These structures can undergo stress relaxation and an extension called creep that is catalyzed by   expansins. Another method of growth of these structures is caused by proton ATPase [A-T-P-"ace"].  Two of these are joined by a middle lamella. A polysaccharide that is highly concentrated in these   structures and in the peels of citrus fruits is used to make jellies. A different polysaccharide that is  highly concentrated in these structures and cotton is used to make paper; those chemicals are pectin  and cellulose. Name these relatively rigid structures not found in protozoa and animals that surround  other types of cells.
These structures can undergo stress relaxation and an extension called creep that is catalyzed by   expansins.
cell walls [prompt on cells]