Refers to the basic processes by which sensory organs and the nervous system respond to stimuli in the environment, and refers to the meaningful interpretations extracted from it.

SENSATION refers to the basic processes by which sensory organs and the nervous system respond to stimuli in the environment, and Perception refers to the meaningful interpretations extracted from it.

Explanation:

The receptors present in the body at different locations sense the changes in inner and outer conditions. A particular receptor is activated by specific stimuli such as thermoreceptors sense the change in the temperatures. This process of detecting the stimuli is followed by the transduction of the stimuli and generation of nerve impulses to send the information to the central nervous system. The whole process is called sensation.

The sensory information sent to the central nervous system is processed and interpreted mainly in the cerebral cortex. This is called perception.

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.

this is true, assuming that the allele is completely recessive and incomplete dominance is not a factor.