For most of a cells life, chromosomes exist in a loose noodle like structure. Why do they become more compact?

For most of the life the chromosomes exists in a loose noodle like structure. They become compact to fit into a very small space.

Explanation: The chromosomes consists of a very long DNA that is linear. The liner DNA also has many proteins associated with it which is called as histone proteins.

These proteins fold and gets packed into a compact form from loose noodle or thread like structure.

This is necessary to get into a compact structure because being in linear form would require much space which is not possible. So as to manage the space and many processes like replication, repair and gene expression it is necessary for the chromosomes to get compact.

atomic number of carbon is 6

electronic configuration of carbon is 1s²2s²2p²

orbital diagram of c is as shown here in the image.

a rain shadow is a dry region of land on the side that is protected against the prevailing winds of a mountain range. the prevailing winds are the winds that occur most of the time in a particular place of the earth

prevailing winds carry air toward the mountain range. as the air rises up over a mountain range, the air cools, water vapor condenses, and clouds form. on this side of the mountains, called the windward side, precipitation falls in the form of  rain  or snow. this dry air produces a  rain shadow.