What type of particles (particulate matter) are responsible for causing the greatest harm to human health?

According the Central Pollution Control Board, particles that are responsible for causing great harm to human health aree of diameter:

What type of forces are responsible for the formation of beta -sheet structure ?

What type of forces are responsible for the formation of alpha -helix formation

What is in between particles of matter ?

What is puberty? Name the hormones responsible for production of sexual characters in human beings?

What is the effect of pressure on particles of a matter ?

What type of forces are responsible for the formation of Cross linking of polypeptide chains.

Read the following passage and answer the questions. When colloidal solutions are viewed under a powerful ultramicroscope, the colloidal particles appear to be in a state of continuous zig-zag motion all over the field of view. This motion was first observed by the British botanist, Robert Brown, and is known as Brownian movement. This motion is independent of the nature of the colloid but depends on the size of the particles and viscosity of the solution. Smaller the size and lesser the viscosity, faster is the motion. The Brownian movement has been explained to be clue to the unbalanced bombardment of the particles by the molecules of the dispersion medium. The Brownian movement has a stirring effect which does not permit the particles to settle and thus, is responsible for the stability of sots. What is Brownian movement ?

What is particulate matter? How do particular matters harm human health?