I believe it is carbohydrates.
The answer is negative controls. These are groups where no phenomenon is probable. They ensure that there is no effect when there should be no effect. Where there are only two possible outcomes, e.g. positive or negative, if the treatment group and the negative control both produce a negative result, it can be concluded that the treatment had no effect. If the negative control group and the treatment group both yield a positive result, it can be inferred that a puzzling variable is involved in the occurrence under study, and the positive results are not only due to the treatment. In other examples, outcomes might be measured as lengths, times, percentages, and so forth.
Answer:
a. Odds ratio = 1.58
b. Inasmuch the odds ratio is greater than 1, this means that higher odds of melanoma exist in people exposed to indoor tanning, than in those not exposed to indoor tanning
Explanation:
For case study
Let 'a' represent the total population of people with melanomia = 696
Let 'b' represent the total number of people with melanomia exposed to indoor tanning = 1107 – 696 = 411 people
For control study
Let 'c' represent the total population = 1500
Let 'd' represent the total number of people not exposed to indoor tanning = 1500 - (0.428 * 1500)
= 1500 - 723
Total number of people not exposed to indoor tanning = 777 people
a. Odds ratio = (a/b) / (d/c) = (696/411) / (777/723)
= 1.69 / 1.07 = 1.58
b. Inasmuch the odds ratio is greater than 1, this means that higher odds of melanoma exist in people exposed to indoor tanning, than in those not exposed to indoor tanning.
The right answer is D (less responsive to antigens)
It is proven that, after puberty, thymus activity (an organ that is included in the lymphatic system, producing T cells that pick up antigens) decreases and that in adult and aged people the thymus has no role. Work done in humans indicate that in fact the cellularity begins to decline from birth in favor of lymphocyte perivascular spaces and connective and adipose tissue, which leads to a decrease in the capture of antigens.
