1) Select the correct statement about human immunodeficiency virus (HIV) a

1) Select the correct statement about human immunodeficiency virus (HIV)

a. HIV must synthesize reverse transcriptase immediately after affecting a cell

b. HIV envelope proteins require either the CXCR4 or CCR5 co-receptor for fusion

c. HIV has a DNA genome

d. Reverse transcriptase synthesizes the copy of the viral RNA  genome that gets packed in the virus particle

2. Place the following phases of a B-cell's life history in the correct chronological order

a. negative selection, positive selection, repertoire assembly, circulate to secondary lymphoid organs, developed into plasma cells

b. circulate to secondary lymphoid organs, repertoire assembly, negative selection, positive selection, develop into plasma cells

c. repertoire assembly, negative selection, positive selection, circulate to secondary lymphoid organs, develop into plasma cells

d. repertoire assembly, negative selection, positive selection, develop into plasma cells, circulate to secondary lymphoid organs

3. Germinal centers in the lymph nodes are the site where____

a. naive B cells are activated by antigen

b. isotope switching and somatic hypermutation occur

c. positive selection of naive B cells occur

d. none of the answers are correct

4. Which of the following contributes to the activation of naive cytotoxic T cells?

a. Dendritic cells with antigens displayed on MHC I receptors

b. Macrophages with antigens displayed on MHC I receptors 

c. Dendritic cells with antigens displayed on MHC II receptors

d. B cells with antigens displayed on MHC II receptors