IMMUNOLOGY

Detailed explanation-1: -Answer and Explanation: Fever is not the first line of defense; it is considered the second line of defense. Suppose the first line of defense couldn’t protect the body, and the pathogen still enters the body. In that case, the second line of defense protects the body, including fever, inflammation, and phagocytosis.

Detailed explanation-2: -Innate immune cells are the body’s first line of defense. They quickly respond to foreign cells to fight infection, battle a virus or defend the body against bacteria. T-cells and B-cells react when invading organisms slip through that first line using a process called acquired immunity (or adaptive immunity).

Detailed explanation-3: -The third line of defence is called the immune response and is SPECIFIC. It involves the production of two types of lymphocytes (B and T cells) which are specific to the invading particle. They work together to attack the pathogen.

Detailed explanation-4: -The first line of defence (or outside defence system) includes physical and chemical barriers that are always ready and prepared to defend the body from infection. These include your skin, tears, mucus, cilia, stomach acid, urine flow, ‘friendly’ bacteria and white blood cells called neutrophils.

Detailed explanation-5: -The innate immune system is the body’s first line of defense against germs entering the body. It responds in the same way to all germs and foreign substances, which is why it is sometimes referred to as the “nonspecific” immune system.

Detailed explanation-6: -Physical and Chemical Barriers (Innate Immunity) Nonspecific Resistance (Innate Immunity) Specific Resistance (Acquired Immunity)