The process of cellular respiration 1. occurs before plants are able to carry out photosynthesis.
2. is performed only by animals.
3. occurs in all living organisms.
4. is performed only by organisms that can't photosynthesize.

3. occurs in all living organisms.

Explanation:

this is the process where organisms are able to break down organic molecules contained in food consumed to acquire energy.

it is a learned trait

explanation:

sheep is a herbivore animal whereas grasshopper belongs to the class chordates but both of them feed on greens.  

if grasshopper and sheep feeding on a pasture land, i do not think both of them will have any impact on each other. however, the number of the species can make difference. since sheep feed on greens, there is a possibility there left no pasture land for the grasshoppers or they may get extinct.