What is the difference between an artery and a vein? an artery carries blood away from the heart; a vein carries blood to the heart. an artery is responsible for carrying blood; a vein is responsible for gas exchange. an artery is responsible for gas exchange; a vein is responsible for carrying blood. an artery carries blood to the heart; a vein carries blood away from the heart.

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.