Many tiny hair-like cilia protrude from the olfactory receptor cell's dendrite into the mucus covering the surface of the olfactory epithelium. The surface of these cilia is covered with olfactory receptors, a type of G protein-coupled receptor.
Respiration -10 to 30. The normal respiratory rate for dogs is 16 to 20 breaths per minute. The normal heartrate is 70 to 160 bpm. Large dogs tend to have slower heart rates so your dog should be in the 70 to 120 bpm range. This varies according to the cardiovascular fitness of the dog, too.
My 16 month old Border Collie recently went to a vet (not my normal vet) for a health certificate. The vet observed that her heartrate was slow - 50 bpm at rest and told me to keep an eye on it. The normal canine heartrate is 60-120 bpm.