Which of the following statements are correct ?

I. Allergy refers to the excessive response of the immune system to specific antigens found in the environment.

II. The tendency to develop allergies can be inherited from parents, and it is characterized by elevated levels of IgG antibodies in the blood.

III. Rheumatoid arthritis which affects many people in our society is an auto-immune disease.

I and III

 The correct answer is Option (3) – I and III

The correct statements are:

I. Allergy refers to the exaggerated response of the immune system to specific antigens present in the environment. When an allergic individual comes into contact with an allergen, such as pollen, dust mites, or certain foods, their immune system overreacts and releases histamine and other chemicals, leading to allergic symptoms.

II. The tendency to develop allergies can be passed down from parents to offspring through genetic factors. Individuals with a family history of allergies are more likely to develop allergies themselves. This genetic predisposition may involve variations in immune system genes or the regulation of immune responses.

In terms of antibody involvement, allergies are typically associated with elevated levels of IgE antibodies, not IgG antibodies. IgE antibodies are produced in response to allergens and play a crucial role in triggering allergic reactions.

III. Rheumatoid arthritis is indeed an autoimmune disease. In autoimmune diseases, the immune system mistakenly attacks the body's own tissues and organs as if they were foreign invaders. In the case of rheumatoid arthritis, the immune system primarily targets the joints, leading to chronic inflammation, pain, and damage.