En una sinapsis química, cuando pasa un impulso nervioso entre una neurona y otra, la membrana de la neurona postsináptica: I. Es permeable al ión sodio Na+. II. Se hace más permeable al ión cloro Cl-. III. Aumenta la permeabilidad al ión potasio K+. Es (son) correcta (s):

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.

the planets have a circular orbit around the sun.

answercalled plucking;