Which of the following is a component of a proton?
up quark
neutron
electron
gluon

up quark

Explanation:

An atom is the smallest particle of  element that can take part in a chemical reaction. It consists of subatomic particles; electrons, neutrons and protons.Electrons are found in the energy levels while protons and neutrons are found in the nucleus.A proton is made up of three parts namely;Two up quarks One down quark, and The gluons The gluons are parts in which the quarks exchange, and this is how the strong nuclear forces works to keen them from getting out.

Yes, endothermic means it turns cold. and some chemical changes include change of tempature.