21.   It breaks down the components of an air sample by heating it and forcing it through hundreds of tiny tubes.

22.   The water forms a tiny hollow tube, like a capillary, that allows the ink, or other materials, to flow to the surface.

23.   These tiny tubes form a structure called the cytoskeleton, which helps cells retain their shape by organizing in either parallel or circular patterns.

24.   They also implanted a tiny tube called a stent that is intended to hold the artery open.

25.   Then doctors snaked a tiny tube down her throat to fix the faulty valve causing the problem.

26.   The army system involves tiny tubes woven into the clothing that move either warm or cold air, depending on the outside temperature.