Cell wall polymer migration

Most slabstock foams are open-celled, that is, the walls around each cell are incomplete. Towards the end of the foaming process, the polymer migrates from the membranes between cells to the cell struts, which results in a porous structure. In some cases, cells near the surface of the foam collapse to form a continuous skin, which may be trimmed off later. 

Peripheral tissues uch as muscle, adipose tissue, and the I acta ting breast contain both hoTmone-sensitive lipnse and lipoprotein lipase. This second lipase, mentioned in the lipoprotein section of Chapter ft, requires apolipoprotein C-II as a cofactor. The lipase is secreted by cells and migrates through the interstitial fluid to the capillary, where it becomes bound to the membrane with its active site exposed to the bloodstream. This binding to the luminal wall of the capillary occurs by attachment to a polymer called glycosaminoglycan. 

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