Questions

What are stars primarily made of?

Article 44 of the Indian Constitution "Uniform civil code for the citizens" deals with _____.

'Ganga Action Plan' initiated by the Union Government aims at

Who among the following has been awarded the Indira Gandhi Award for National Integraty on October 31, 2017?

Who among the following is the winner of the National Badminton Championship (Men), 2017?

Which of the following sportspersons recently wrote the autobiographical book 'Ace Against Odds'?

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.

The children said, "They were busy playing thus they did not notice the stranger."

Read the passage carefully and choose the best answer to each question out of the four alternatives and click the button corresponding to it.

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 happens when an antigen comes in contact with lymphocytes?