Question

Mention the source and the role of the following in providing defence against infection in the human body: (I) Histamine (II) Interferons

Hint:

Histamine aids in the inflammatory response, while interferons are crucial for preventing viral replication and enhancing immune cell activity.

Answer 1

(I) Histamine:

Source: Histamine is produced and stored in mast cells and basophils.
Role: Histamine plays a key role in the inflammatory response. It is released during an allergic reaction or infection, causing blood vessels to dilate and become more permeable. This allows white blood cells and proteins to enter the affected tissues and fight the infection.
(II) Interferons:

Source: Interferons are produced by infected cells, primarily by virus-infected cells as part of the immune response.
Role: Interferons inhibit viral replication by interfering with the ability of viruses to infect healthy cells. They also stimulate the activity of immune cells like macrophages and natural killer cells to attack infected cells.