Immunity, neutrophils

  A. IMMUNITY:-

 Immunity is defined as the capacity of the body to resist pathogenic agents.

 It is the ability of body to resist the entry of different types of foreign bodies like bacteria , virus , toxic substance.,etc.

 Immunity is of two types:-

 I. Innate immunity

 • Innate immunity is the inborn capacity of the body to resist pathogens.

 • By chance ,of the organism enter the body , innate immunity eliminates them before the development of any disease.

 • It is the first line of defense against any type of pathogens.

 • It is also called the natural or non-specific immunity.

 II. Acquired immunity

 • Acquired immunity is the resistance developed in the body against any specific foreign body like bacteria, viruses , toxins , vaccines or transplanted tissues.

 • This type of immunity is also known as specific immunity .

 • It is the most powerful immune mechanism that protects the body from the invading organsims or toxic substances.

 • Two types of acquired immunity develop in the body

 i. Cellular immunity

 ii. Humoral immunity

Lymphocytes are responsible for the development of these two types of immunity.

 B. NEUTROPHILS

 • Neutrophils are Granulocytes types of WBC.

 • Neutrophils which are also known as polymorphs have fine or small granules in the cytoplasm.

 • The granules take acidic and basic stains.

 • When stained with leishman's stain the granules appear violet in color.

 • Nucleus is multiobed . The number of lobws in the nuclues depends upon the age of cell.

 • In younger cells, the nucleus is not lobed. And in older neutrophils , the nucleus has 2 to 5 lobes.

 • The diameter of cell is 10 to 12 μ.

 • the neutrophils are ameboid in nature.