2. Which of the following parts of the IgG molecule are not involved in binding to an antigen? A) Fab B) Fc C) Heavy chain D) Light chain E) Variable domain

Which of the following destroys virus-infected cells?   Question 6 options:   A)  cytotoxic T cells   B)  B cells   C)  T helper cells   D)  dendritic cells

10. Te cells are distinguished from the other cell types by producing A). T cell receptors (TCR). B). CD8. C). CD3. D). IFN. E). TLR. 11. Why does it takes nearly two weeks to develop meaningful adaptive immune responses to fight off a new pathogen? A). It took that amount of time to modify DNAs for the receptors recognizing the pathogen. B). It took that amount of time for the innate immunity to complete its role. C). It took that amount of time to select the cells recognizing new pathogens. D). All of the above. E). None of the above. 12. Which attracts white blood cells to the damaged tissue? A). Antibodies B). Chemokines C). IFNs D). IL-4

Which part of the immune system does not target specific new variants of the COVID 19 invaders? A) antibodies B) specific defense C) antigens D) innate response