If atoms share two , three or more pairs of electrons..they are covalent bonds..for example, methane
if the atoms share only a lone pair of electron contributed by only one of the combining atoms but shared by both ..then it is a coordinate bond ..for example, ammonium ion
They both grow and develop.
Snow melting would be due to the temperature
Answer:
Matthias Schleiden and Theodore Schwann
A RADIOLOGIST
IS THE ONE WHO DOES X-RAYS