Endosmosis is the movement of water inside the cell when the cell is in hypotonic solution(surrounding medium has more water as compared to inside).The water moves from higher concentration to lower concentration.This causes the cell to swell up!
Contact force- forces acting by direct contact between the bodies, for example, frictional force (it cannot act without contact) as well as muscular force.
Non-contact force- forces which do not require any contact between bodies and act from some distance, eg gravitation and magnetic forces, (you feel gravity even when you are in the air without touching anything (or in freefall)).
Maths and science both are my favourite subjects. both are very interesting. in science we came to learn new new things about are body, chemical reactions.. in maths we enjoy solving question especially questions related to trigonometry chapter.