Chapter 14-olfaction Flashcards
Odor
The translation of a chemical stimulus into a smell sensation
Odorant
A molecule that is defined by its physiochemical characteristics, which are capable of being translated by the nervous system into the perception of smell; physical thing you smell
In order to be smelled, odorants must b
Volatile, small, hydrophobic
Human olfactory apparatus contains
Olfactory clefts and olfactory epithelium
Olfactory cleft
Narrow space at the back of the nose into which air flows
Olfactory epithelium
Mucous membrane in the human nose whose primary function is to detect odorants
Primary function of the nose
Breathe; filter, warm and humidify air that you breathe
Odor receptors sites are located where
On the cilia of olfactory sensory neurons where odorant molecules bind
Odor receptors are what kind of receptors
Chemoreceptors; receptive sites bind with molecules
Mitral cells receive projections from how many and what type of receptors
About 200, same type of receptor; convergent, lose spatial information
How many different receptor types are ther
About 1000, respond to distinct chemical molecules or parts of molecules
How many molecules are needed to activate odor receptors
7-8
Humans have how many receptors
6 million
Olfactory pathway
Olfactory bulb, Piriform cortex, entorhinal cortex, limbic system, orbitofrontal
Olfactory bulb
Olfactory info first processed here, 1 in each hemisphere that corresponds ipsilaterally to each nostril
Primary olfactory cortex also known as
Piriform cortex
Entorhinal cortex
Old, sensory association area, connect to the limbic system
Limbic system
Emotion (fear) and memory, base survival learning