DP Biology (last assessment 2024)
Question 19N.3.HL.TZ0.c
Date | November 2019 | Marks available | [Maximum mark: 2] | Reference code | 19N.3.HL.TZ0.c |
Level | HL | Paper | 3 | Time zone | TZ0 |
Command term | Outline | Question number | c | Adapted from | N/A |
c.
[Maximum mark: 2]
19N.3.HL.TZ0.c
Outline the main principles of the Enzyme-Linked Immunosorbent Assays (ELISA) test.
[2]
Markscheme
a. «ELISA» uses antibodies to detect a target antigen «to a pathogen» ✔ OWTTE
b. antigen attached to substrate ✔
c. the antibody «if present» will attach to the antigen ✔
d. «suitable» enzyme attached to antibody ✔
e. «enzyme» colour reaction shows the presence of antibodies to the antigen/pathogen ✔
