Contraction of muscles is an example of how the motor protein interacts with the cytoskeletal elements called to produce movement.

Explanation:

Muscle contraction is a mechanism in which tension is generated within muscle fibers. It is based on the length and tension of the muscle. This process is neurogenic in nature so motor neurons play an important role in the process of contraction. Myosin and actin filaments play an important role when they interact. There is a formation of cross-bridges that regulates the process of contraction and relaxation.  

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 corpus luteum secretes estrogens and progesterone. the latter hormone causes changes in the uterus that make it more suitable for implantation of the fertilized ovum and the nourishment of the embryo. if the egg is not fertilized, the corpus luteum becomes inactive after 10–14 days, and menstruation occurs.

i hope this : )