Glucose that circulates in the bloodstream is kept within a normal range by
O being used up for energy or being stored in
the form of glycogen.
the hypothalamus raising or lowering internal
body temperature.
a positive feedback mechanism controlled by
the hormone insulin.
o the enlarging of blood vessels when body
temperature goes beyond the set point.

Why is a lunch consisting of pizza, fruit, and salad a better choice than a lunch with the same number of calories from pizza alone? a)both lunches provide the same amount of energy but the lunch of pizza, salad, and fruit provides more nutrients. b)both lunches provide the same amount of nutrients but the lunch of pizza, salad, and fruit provides more energy. c)both lunches are healthful but the lunch of pizza, salad, and fruit provides more energy for metabolism. d)both lunches are healthful but the lunch of pizza, salad, and fruit is likely to have a higher fat content.

The breakdown of peptides into amino acids is an example of . the release of insulin after eating a large meal is an example of .

Why do rna viruses appear to have higher rates of mutation? a) rna nucleotides are more unstable than dna nucleotides. b) replication of their genomes does not involve proofreading. c) rna viruses can incorporate a variety of nonstandard bases. d) rna viruses are more sensitive to mutagens.