Answer to Question 1
Osteoporosis, literally meaning porous bones, is a condition in which bones lack the minerals required to keep them strong. In osteoporosis, bones-primarily of the hip, wrist, and spine-become so weak and brittle that they fracture readily. The process begins slowly in the third and fourth decades of life. Women are especially susceptible after menopause because of the accompanying loss of estrogen, which increases the rate at which bone mass is broken down. Although osteoporosis is viewed primarily as a woman's disease, more than 30 percent of all men will be affected by age 75.
Answer to Question 2
The typical U.S. diet is too high in calories, sugar, saturated fat, and sodium and not high enough in whole grains, fruits, and vegetables-factors that undermine good health. On a given day, nearly half of the people in the United States eat no fruit and almost a fourth eat no vegetables.
Bones of the spinal column.
Climatic cause and effect linkages
Classification of bones by shape.
The ancestral and modern-day tomato. (b) Phenotypic effect of the fw2.2 transgene in the tomato
The effect of gene–environment interaction
An example of an allosteric effect