Air pollution harms animals as a result of direct exposure to contaminants and destruction of their habitats, food and water sources. For instance, acid rain, which forms when pollutants in the... Air pollution harms animals as a result of direct exposure to contaminants and destruction of their habitats, food and water sources. For instance, acid rain, which forms when pollutants in the... Star Gazing
1 The cilia of the sensory neurons are immersed in a layer of mucus. 2  Odorant molecules (molecules that we can smell) dissolve in the mucus and. 3  bind to receptors on the cilia.4  These are 7-pass transmembrane proteins. 5  Binding of the odorant activates a G protein coupled to the receptor on its cytoplasmic side. bind to receptors on the cilia. 2  These are 7-pass transmembrane proteins. 3  Binding of the odorant activates a G protein coupled to the receptor on its cytoplasmic side. 4  This activates adenylyl cyclase, an enzyme embedded in the plasma membrane of the cilia.
As they feed, anaerobic bacteria produce metabolites that have characteristically noxious smells. One set of smells is related to sulfur compounds. This is the source of that characteristically ârotten eggâ smell associated with bad breath secondary to post-nasal drip. Another set of smells is associated with polyamines that produce the classic putrescent odor of decay.