In parasitism, the organism that is is called the while that which is harmed is called the .

The correct answer for the blank is - Parasite and Host.

Parasitism is a type of biological interaction between two organisms where one organism lives on the surface or inside the body of another organism in order to complete its life cycle and obtain essential nutrients. This organism is called parasite and the other is called host, which is harmed usually by that parasite.

answer; i believe that the correct answer is (light);

layer 3 is younger than layer 6.