Explain how someone who was infected with SARS-CoV-2 could still test negative two days after getting infected. (think of how viruses replicate compared to bacteria)

1) SDS PAGE gels can be probed with NBT/BCIP to perform an immunoblot true/ false 2) the direction of migration of protiens through a matrix is due to most proteins in natur having a net negative charge  true/false 3)  PBST  is a buffer that is used for blocking the membrane during immunoblotting. true/false 4) the buffer used during for transferring proteins to nitrocellulose methanol. true/false 7) The size of the pores of a polyacrylamide gel dcreases as concentrations of polyacrylamide increases. True or false 10) The secondary antibody used in laboratory for western blotting is conjugated to which enzyme  A) Alkaline decarboxylase B) GAPDH C) Alkaline Phosphatase D) Horseeradish peroxide 13) In protien electrophroresis, what reagent present in the sample buffer is used to eliminate difference in the charge densities of protein A) SDS B) 2- mercaptoethanol C) Tris-HCL pH6.8 D) Tris- HCL PH 8.8

please explain SARS-CoV-2 spreads through cell-to-cell transmission

How could a false negative and false positive test occur in the antibody test for coronavirus? Explain your answer by discussing how the test works.-A false postive can occur in a antibody test due to the test being highly specific. While the test is suppose to detetect the antibodies of Sars-Cov-2, an antibody test that has low specificity will detects other antibodies to other viruses

Explain how people who have gotten vaccinated can still get influenza. Give an immunological explanation

Explain why a different influenza vaccine is necessary every year. How is this different from the development of pandemic versions? Please include in your answer the terms antigenic shift and antigenic drift.