Discuss each of the following interspecific relationships, including reference to the species involved, their role in the interaction, and the specific characteristics of the relationship:
(a) Mutualism between ruminant herbivores and their gut microflora
(b) Commensalism between a shark and a remora
(c) Parasitism between a tapeworm and its human host
(d) Parasitism between a cat flea and its host.