PET scans of areas of their brains activated by thirst showed reactions -- particularly in the cingulate cortex. In the elderly, drinking a much smaller volume of water is needed to cause that area of brain activation to subside, said Egan, who is an expert on neuro-imaging.
What is Nutrient Density? It is a measure of the nutrients provided per calorie of food, or the ratio of nutrients to calories (energy). Foods that supply generous amounts of one or more nutrients compared to the number of calories they supply are called nutrient dense.
Population Density- measurement of population using volume or unit area. Population density (in agriculture : standing stock and standing crop) is a measurement of population per unit area or unit volume; it is a quantity of type number density. It is frequently applied to living organisms, and particularly to humans. It is a key geographic term. This question is archived.