These macromolecules are polar [polar: having different ends] because they are formed by head to tail condensation of polar monomers. Let's look at the three major classes of macromolecules to see how this works, and let's begin with carbohydrates.
Bostwick Steel Lath Company advertisement for steel truss loop type metal lath in 1920. A lath or slat is a thin, narrow strip of straight-grained wood used under roof shingles or tiles, on lath and plaster walls and ceilings to hold plaster, and in lattice and trellis work.
Narrow strips of wood, called lath, were nailed horizontally across the vertical studs. Lath can be defined as thin, flat pieces of wood that form a foundation for supporting plaster. It is a type of backing material used as a base or for groundwork. These laths were placed close together (about 3/8 inch apart).Once complete, several coats of plaster were layered on top to solidify the framework.laster can be defined as a mixture of lime and sand or cement and water that is applied over walls and ceilings on top of lath, to form a smooth hard surface that can be painted over once dry.