Questions

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The antigen-antibody immunological reaction is used to be regarded as typical of immunological responses. Antibodies are proteins synthesized by specialized cells called plasma cells, which are formed by lymphocytes (cells from the lymph system) when an antigen, a substance foreign to an organism's body, comes in contact with lymphocytes. Two important manifestations of antigen-antibody immunity are lysis, the rapid physical rupture of antigenic cells and the liberation of their contents into the surrounding medium, and phagocytosis, a process in which antigenic particles are engulfed by and very often digested by macrophages and polymorphs. The process of lysis is executed by a complex and unstable blood constituent known as complement, which will not work unless it is activated by a specific antibody; the process of phagocytosis is greatly facilitated when the particles to be engulfed are coated by a specific antibody directed against them.

What are antibodies?

In the following question, a sentence has been given in Direct/Indirect speech. Out of the four alternatives suggested, select the one which best expresses the same sentence in Indirect/Direct speech.

Zenab said to me, “My father is a dentist.”

Who was the Guru of the music maestro Tansen?

Who wrote the Indian historical fiction novel 'The Rise of Sivagami' published in March 2017?

Which is the fastest land animal in the world?

If D and E are points on the sides AB and AC respectively of a triangle ABC such that DE||BC. If AD = x cm, DB = (x – 3) cm, AE = (x + 3) cm and EC= (x – 2) cm, then what is the value (in cm) of x?

The length of a chord which is at a distance of 5cm from the centre of a circle of radius 13cm is

Permanent settlement was a feature of___________.