Growth

Growth in insects occurs between molts, and in bees molting occurs as the pupa turns into an adult bee. Before a developing bee sheds its exoskeleton, the larva, a little white worm growing within a waxen cell of honeycomb being used as a nursery, enlarges itself and acquires the adult form. As much internal reorganization of the pupa's body takes place, chitin and protein subunits from the old exoskeleton recycle within the hemocoel, so that many of these same components find positions in the new adult cuticle that forms underneath the old. Producing normal chitin requires a precise spatio-temporal ordering of molecules. This ordering depends on the geometries of receptors and their positions in space.

Sorting and processing molecules in the hemocoel begins in the hemolymph. Small molecules in one part of a bee end up in complex structures in another. Water is a natural starting point for the insect's molecular manufacturing. Hemolymph, largely water, is dense, highly disordered, and simultaneously transports a diversity of cells and molecules. Manufacturing cuticle includes: acquiring and ordering molecules from the hemolymph, transforming streams of incoming molecules into streams of product, and then storing or arranging these strings to build the complex three-dimensional object that is cuticle. To analyze these sequences, we must ultimately understand: the assembly sequence, how molecules are transported, the timing of synthetic cycles, their energy requirements, the error rates and the error sensitivities.

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