Which of the following errors would result in positive results for all samples in an ELISA assay (including negative controls)?

A. Failure to perform the wash step after initial incubation with controls/samples,
B. Failure to perform the wash step after incubation with secondary antibody.
C. Failure to perform the wash step after incubation with primary antibody.

B. Failure to perform the wash step after incubation with secondary antibody, this because If the test sample did not contain antigen, primary antibody did not bind to the wells, so the secondary antibody did not have anything to bind to and was flushed out in the wash step, so the secondary antibody determines the antibody that appears.

The correct option is option B.

Explanation:

Failure to perform the wash step after incubation with secondary antibody.

This is true because the lack of the antigen causes the first antibody to pass through during the washing step. Thus this will lead to no substance for the second antibody to hold on and thus can lead to positive results in all the samples.

before, trains worked using the steam engine. thus, it uses heat so it is crucial to apply heat balance. the steam engine absorbs energy during the stage of boiling water. so, this is the endothermic reaction. when the steam is used to work the piston, it has to release this energy through running the train. the excess energy is released as an exhaust to the chimney. this is the exothermic process because it releases energy to the surroundings.