1. ANATOMY Unit 2 NOTES: Taste, Touch, Smell

2. (1) Smell
Smell is the binding of organic molecules to receptors deep within the nose.
Your nose is lined with olfactory receptors…
Air flows in carrying organic molecules
Organic molecules dissolve in mucus lining
Organic molecules bind to receptors
Impulse sent through Olfactory Nerve

4. (2) Taste Taste is the binding of molecules to receptors on tongue.
Tongue is covered in papillae projections, covered in “taste buds” or gustatory cells:
Organic Molecules dissolve in saliva
Molecules bind to gustatory cells
Impulse sent to brain

6. (3) Taste Regions on Tongue
Sweet:
Receptors bind with monosaccharides and amino acids
Location: Front & Center of Tongue
Sour:
Receptors bind with hydrogen ions (acid)
Location: Sides of Tongue
Salty:
Receptors bind with metal ions
Location: Front & Sides of Tongue
Bitter:
Receptors bind with alkaloids (typically nitrogenous)
Location: Very Back of Tongue

8. (4) Touch Touch = Pressure against skin
Skin contains pressure + temperature receptors…
Meissner’s Receptors = Super Sensitive
Palms, Feet, Lips, Eyelids
Minimal pressure needed
Paccinian Receptors = Deep Receptors
Pressure + Vibration
Nociceptor Receptors= Sense Pain
Most Abundant on body
Thermoreceptors = Sense Temperature
Individual neurons for hot and for cold
Increase nerve impulses with changes in temperature