Numerical Problems/ISC/Class 12
Created by Titas Mallick
Biology Teacher • M.Sc. Botany • B.Ed. • CTET (CBSE) • CISCE Examiner
Created by Titas Mallick
Biology Teacher • M.Sc. Botany • B.Ed. • CTET (CBSE) • CISCE Examiner
Numerical Problems - Human Health and Disease
After a primary exposure to an antigen, the body starts producing antibodies after about 7 days, and the antibody level peaks around 14 days. In a secondary exposure to the same antigen, antibodies are produced within 2 days and reach a much higher peak in 7 days. If the primary response produces 100 units of antibodies at its peak, and the secondary response produces 10 times more antibodies, how many units of antibodies are produced at the peak of the secondary response?
Solution:
Antibody units in secondary response = 100 units * 10 = 1000 units
Therefore, 1000 units of antibodies are produced at the peak of the secondary response.
In a clinical trial for a new vaccine, out of 1000 vaccinated individuals, 20 contracted the disease. In a control group of 1000 unvaccinated individuals, 200 contracted the disease. Calculate the efficacy of the vaccine.
Solution:
Vaccine efficacy is a measure of how well a vaccine prevents disease. It can be calculated using the formula:
Vaccine Efficacy = ((Rate in unvaccinated group - Rate in vaccinated group) / Rate in unvaccinated group) * 100
Vaccine Efficacy = ((0.2 - 0.02) / 0.2) * 100 Vaccine Efficacy = (0.18 / 0.2) * 100 Vaccine Efficacy = 0.9 * 100 = 90%
Therefore, the efficacy of the vaccine is 90%.
/Numerical-Problems/ISC/Class-12/Class_XII_Biology_Chapter_Human_Health_and_Disease_Topic_Immunity_Numerical_Problems.mdx