1. What are the three main components of the inflammatory response and what are their functions? (3

marks)

- The three main components of the inflammatory response are:

 - Vascular changes: These include vasodilation, increased vascular permeability, and leukocyte adhesion.

They allow more blood flow, fluid, and immune cells to reach the site of injury or infection.

 - Cellular events: These include the recruitment and activation of leukocytes, such as neutrophils,

monocytes, macrophages, and lymphocytes. They mediate the elimination of pathogens, foreign materials,

and damaged cells.

 - Mediators of inflammation: These include chemical substances that are released or activated by various

cells and tissues, such as cytokines, chemokines, histamine, prostaglandins, complement, and coagulation

factors. They regulate and amplify the inflammatory response by affecting vascular changes, cellular events,

pain, fever, and systemic effects.

2. What are the four cardinal signs of inflammation and what are their underlying mechanisms? (4 marks)

- The four cardinal signs of inflammation are:

 - Rubor (redness): This is caused by vasodilation and increased blood flow to the inflamed area.

 - Calor (heat): This is also caused by vasodilation and increased blood flow, as well as increased metabolic

activity of cells in the inflamed area.

 - Tumor (swelling): This is caused by increased vascular permeability and leakage of fluid and plasma

proteins into the interstitial space.

 - Dolor (pain): This is caused by the stimulation of nerve endings by mediators of inflammation, such as

prostaglandins and bradykinin, as well as by mechanical pressure from swelling.

3. What are the differences between acute and chronic inflammation in terms of duration, causes, cellular

events, and outcomes? (4 marks)

- Acute inflammation is a short-lived (hours to days) response to an acute injury or infection. It is

characterized by the predominance of neutrophils and the resolution of inflammation once the stimulus is

removed or eliminated. The outcomes of acute inflammation are either healing by regeneration or repair by

scar formation.

- Chronic inflammation is a prolonged (weeks to months) response to a persistent or recurrent injury or

infection. It is characterized by the predominance of macrophages and lymphocytes and the persistence of

inflammation despite attempts to resolve it. The outcomes of chronic inflammation are either healing by

repair with fibrosis or tissue damage with loss of function.

4. What are some examples of causes of chronic inflammation? (2 marks)

- Some examples of causes of chronic inflammation are:

 - Persistent infections by microorganisms that are difficult to eradicate, such as tuberculosis, leprosy,

syphilis, helicobacter pylori, etc.

 - Prolonged exposure to foreign materials that cannot be degraded or removed, such as asbestos, silica,

sutures, implants, etc.

 - Autoimmune diseases in which the immune system attacks self-antigens, such as rheumatoid arthritis,

systemic lupus erythematosus, inflammatory bowel disease, etc.