71.In comparison with the RDA for vitamin E, about how : 1401672.
71.In comparison with the RDA for vitamin E, about how many times higher is the Tolerable Upper Intake Level?
72.Increasing the amount of polyunsaturated fats in the diet increases the need for which vitamin?
73.An extremely high dose of vitamin E may interfere with the action of vitamin K, causing which of the following problems?
74.Which of the following describes a free radical?
a.an inactive vitamin
b.an unphosphorylated vitamin
c.a molecule of unbound cobalamins
d.a molecule with at least one unpaired electron
75.Which of the following is a characteristic of vitamin C?
76.In which of the following capacities does vitamin C function?
a.coenzyme for energy release
b.cofactor in collagen formation
c.cofactor with calcium in blood coagulation
d.coenzyme in the formation of red blood cells
77.Which of the following proteins requires ascorbic acid for its formation?
78.Which of the following represents the results of well-controlled studies of vitamin C supplementation on the resistance to, and recovery from, colds?
a.There was a reduction in the duration of colds by 50 percent on the average.
b.There was only a minor effect on reducing the number and severity of colds.
c.There was a slight, but consistent, reduction in the duration of colds in people who consumed at least 200 g a day.
d.There was a significant reduction in the number of colds only in people who consumed more than 3 g per day.
79.Which of the following is the reason why vitamin C supplements might be beneficial in treating the common cold?
a.They deactivate histamine.
b.They reduce episodes of diarrhea.
c.They destroy intestinal pathogens.
d.They alter hypothalamic control of body temperature.
80.Which of the following vitamins is known to deactivate histamine, a substance that causes nasal congestion?