It must be volatile (able to float through air) and small (less than 5.8 E-22)
What is the primary purpose of the nose?
to filter, warm, and humdifiy the air we breathe.
What are the 3 types of cells in the olfactory epithelium and what is their purpose?
Supporting cells- provides metabolic and phyiscal support for the OSNs.
Basal cells- precursor cells
Olfactory sensory neurons- main cell type, contain cilia on its dendrites that have receptor cites for odorant molecules.
What is the cribriform plate?
bony structure at the level of the eybrows between the nose and the brain. It has tiny holes that pass the axons on the ends of the OSNs.
What is anosmia and some of its causes?
smell blindness; Usually it is caused by upper respiratory tract infection or snionasal disease. Can also be caused by head trauma, or different medications. Usually it is not congenital.
What are the two sets of nerves involved in olfaction?
Olfactory (I) and Trigeminal (V). Olfactory is actually smell, while trigeminal is the feeling that goes along with some smells.
Describe the two main theories associated with smell.
Shape-pattern theory- odorants activate an array of olfactory receptors in the olfactory epithelia, producing specific firing patterns which determine the scent
Vibration theory-every perceived smell has a different vibrational frequency. molecules that produce the same frequencies smell the same. The problem with this theory is that it does not explain specific anosmias and different scents produced by stereoisomers.
Where does majority of olfactory processing take place?
in the right hemisphere of the brain.
What is the difference between receptor adaptation and cross adaptation?
receptor adaptation is when the receptors stop responding to the odorant because of continuous exposure causing detection of the odorant to stop. Cross adaptation is when the detection of an odorant is reduced after being exposed to another one.