Which of the following statements are correct regarding immunity?

(I) Innate immunity is achieved through various types of barriers.

(II) Acquired immunity is present from birth and inherited from parents.

(III) Acquired immunity can be categorized into antibody-mediated and cell-mediated immunity.

(IV) Innate immunity is also known as specific immunity.

(V) Acquired immunity involves specialized cells (T-cells and B-cells) and circulating antibodies.

I, III and V

The correct answer is Option (3) -I, III and V

Explanation of correct options:

I. Innate immunity is accomplished by providing different types of barriers. Innate immunity is the first line of defense against pathogens and is achieved through various physical, chemical, and cellular barriers. Examples of innate immunity barriers include the skin, mucous membranes, stomach acid, and phagocytic cells.

III. Acquired immunity can be divided into antibody-mediated and cell-mediated immunity. Acquired immunity, also known as adaptive immunity, develops over time as a response to specific pathogens. It can be further categorized into antibody-mediated immunity (humoral immunity) and cell-mediated immunity. Antibody-mediated immunity involves the production of antibodies by B-cells to neutralize or eliminate pathogens, while cell-mediated immunity involves the activation of T-cells to directly destroy infected cells.

V. Acquired immunity consists of specialized cells (T-cells and B-cells) and antibodies that circulate in the blood. Acquired immunity involves specialized cells, specifically T-cells and B-cells, which play crucial roles in the immune response. T-cells recognize and eliminate infected cells directly, while B-cells produce antibodies that bind to specific pathogens and mark them for destruction. These cells and antibodies circulate in the blood to provide a systemic defense against pathogens.

Explanation of incorrect options:

IV. Innate immunity is also called specific immunity.It is incorrect . Innate immunity is often referred to as nonspecific immunity because it provides a general defense mechanism against a wide range of pathogens. It does not target specific pathogens but rather provides immediate protection against various types of infections.

II, "Acquired immunity is present from birth and inherited from parents," is incorrect. Acquired immunity is not present from birth but is developed over time through exposure to pathogens or through vaccination. It is not inherited from parents but can be transferred from mother to child through breast milk or placenta (passive immunity) until the child develops its own acquired immunity.