2. T F Studies have shown that people in lower-income groups tend to live longer and expe-
rience less disability than those in upper-income groups
3. T F Poverty particularly affects older Americans and families headed by single mothers.

Feedback mechanisms regulate the rate of enzyme activity, effectively "turning off' an enzyme in a reversible way until more product is needed. which of the following would be most effective as a feedback mechanism? a. reduced concentration of product b. increased concentration of substrate c. a change in ph d. temporary binding of a non-substrate molecule in the active site