Suppose you are camping. looking up into the sky, you see what looks like hundreds of shooting stars. what are you seeing and what causes phenomenon

Meteor Shower caused by space debris present in Earth's orbit

Explanation:

When rocks enter in Earth's atmosphere and burn due to friction, they appear like shooting stars and are known as Meteors. When comets (in rare cases asteroids as well) revolve around the Sun, they leave behind a lot of debris consisting of dust and rocks. Orbit of some of the comets intersect with Earth as well which means that on the orbit of Earth around the Sun there are patches with high density of such rocks (known as meteoroids). When Earth crosses through such patches, a lot of meteors (sometimes 100+ in one hour) can be seen in the sky. Such events are known as Meteor Shower.

the sugar-phosphate backbone forms the structural framework of nucleic acids, including dna and rna. this backbone is composed of alternating sugar and phosphate groups, and defines directionality of the molecule.