Nematode Body Structure. The phrase tube-within-a-tube is a convenient way to think of nematode body structure, and also a term used to refer to a major trend in the evolution of triploblastic metazoa (Brusca and Brusca, 1990 Invertebrates).
Neutrals and Universal Colors. Let me explain in details... In general, neutrals include black, white, gray (mix black with white and you've got gray) and different shades of brown. Nowadays a color can be called a neutral based on how effectively it can blend in with other colors. Basically, they match with all colors and color combinations - and don't create much of an emotion.
Whites and Neutrals. Whites and neutrals such as gray, beige, tan or cream, create a clean, airy backdrop for any design or color scheme. White is often associated with cleanliness, innocence and goodness. Because they are neutral, these colors can be calming, and they make a room feel larger and more airy. To add drama, while keeping things calm and spacious, add pops of color with furnishings and fabrics. Sherwin Williams: Color Tips: Choosing Interior Paint Colors.