Question
(c) If pathogens do enter the body the immune system tries to destroy the pathogens Describe how the immune system defends the body against disease (2)
Answer
4.5
(187 Votes)
Elliot
Advanced · Tutor for 1 years
Answer
1. Recognition of the pathogen2. Activation of immune response3. Elimination of the pathogen
Explanation
## Step 1: Recognition of the PathogenThe immune system identifies the pathogen by distinguishing self from non-self. This is done through receptors on immune cells that recognize unique molecules on the pathogen.## Step 2: Activation of Immune ResponseOnce the pathogen is recognized, the immune system activates various immune cells like T-cells and B-cells. T-cells can directly attack infected cells, while B-cells produce antibodies that can neutralize the pathogen.## Step 3: Elimination of the PathogenThe immune response leads to the destruction or neutralization of the pathogen. Phagocytic cells like macrophages engulf and digest the pathogen, while cytotoxic T-cells kill infected cells. Antibodies can also neutralize the pathogen, making it easier for phagocytes to eliminate it. The immune response also involves the activation of the complement system, a series of proteins that assist in the destruction of pathogens. The response is coordinated and regulated to ensure that the pathogen is effectively eliminated without excessive damage to the host's own tissues.