The tick attaching itself to the skin of the dog is the parasitic relationship because the tick is relying on the dog as a host in order to live.
Nerves that detect deep pressure are called Pacinian corpuscles.
Pacinian corpuscles are microscopic onion-shaped nerve structures that are situated in the dermis and hypodermis. Pacinian corpuscles detect deep pressure and vibration. This nerve has a myelinated nerve ending in the middle of its structure and the external layer contains flattened cells, a lymph-like fluid and collagen fibers. The structure of pacinian corpuscles provides a fast response and rapid recovery by transmitting fast events. This make them sensitive to pressure and vibration.