IMMUNOLOGY

Detailed explanation-1: -Your immune system sends out its first responders: inflammatory cells and cytokines (substances that stimulate more inflammatory cells). These cells begin an inflammatory response to trap bacteria and other offending agents or start healing injured tissue. The result can be pain, swelling, bruising or redness.

Detailed explanation-2: -While the sensation is a very individualized experience, inflammation typically causes pain because the swelling and buildup of tissue starts pressing against nerve endings. This pressure sends pain signals to the brain, causing discomfort.

Detailed explanation-3: -Five cardinal signs characterize this response: pain, heat, redness, swelling, and loss of function. In some cases, though, there may be no symptoms of inflammation at all.