According to the shape of screening impurities to choose hole-shaped sieve plate(move out long, Diamond impurities) and the slit-shaped sieve plate(move out particles shape impurities and emplastic).
According to the shape of screening impurities to shoose hole-shaped sieve plate (move out long ,Diamond impurities)and the slit-shaped sieve plate (move out particles shape impurities and emplastic).
These neurons migrate down from the olfactory placode and get embedded in the cribriform plate, which is a bone plate that separates the nasal cavity from the brain, forming the olfactory bulb.