Answer:
The correct answer of question 1 is option a.
Explanation:
Exposure to any infectious agent, that is, when the agent has bypassed the first and second lines of defence, it results in the activation of cell-mediated immunity.
Antigen of the infectious agent is represented to T- cell with the help of antigen presenting cell (APC) such as dendritic cell or macrophages. Activated T-cells release cytokines which attracts more and more T-cells.
In addition, it increases the proliferation of T-cells. Some T-cells convert into T-helper cells and some in T-cytotoxic cells and some in T-memory cells.
The T-cytotoxic cells digest the infected cells and T-helper cells further activate more macrophages, dendritic cells, and other lymphocytes such as B cells with the help of cytokines.
Thus, the infection is faught and cleared from the body.
The correct answer of question is option c.
Being soluble in water, the excess amount of vitamin C can be easily excreted out of the body along with urine.
