Chemical Senses

Question 1

smell

Answer 1

detects food, mates, predators; excite sexuality, warning of danger

Question 2

odorant properties

Answer 2

water soluble, sufficient high vapor pressure, low polarity, some ability to dissolve in fat, surface activity, small molecular weight (less than 294)

Question 3

the nose

Answer 3

olfactory region is 2.5cm^2 per nostril w 59 mil sensory cells, cilia project through lipid rich mucous layer produced by bowman’s glands, 8-20 cilia per receptor, receptor neuron regeneration!!!

Question 4

nerve connection

Answer 4

neuronal cells form axon bundles> cells penetrate ethmoidal cribiform plate to contact olfactory bulb> connect w post synaptic cells forming glomeruli> which connect to form mitral cells (connect to corticomedila amygdala via olfactory nerve tract)

Question 5

odorants binding proteins

Answer 5

bind odorants w one end to fat w the other in mucous, increase concentration of odorants and transport through mucous layer

Question 6

smell receptors

Answer 6

G- protein coupled receptors, buck and axel (18 diff members of a multigene fam & 7 transmembrane proteins specific to olfaction)

Question 7

special smelling system

Answer 7

vomeronasal system

Question 8

taste

Answer 8

chemoreceptors (receptors that respond to specific molecules), sensilla (each has a small hole allowing molecules to reach sensory cells)