WARM UP 4/23 1. What gland produces tears? 2. What are the 1 st 3 cranial nerves? 3. What part of the brain is for balance? 4. What part of the brain reg. Thirst and pleasure? 5. What is the largest brain part? 6. What does the midbrain do? 7. What does the pons do? 8. Why are some people near-sighted?

NOTES CH 11 4/23 The sense of smell and taste

OLFACTION = SMELL Olfactory cells high in nasal cavity

Odors attach on moist olfactory hairs on cells This starts an action potential Message travels through olfactory nerve to cerebrum temporal lobe Brain interprets smell Humans can detect about 10,000 diff. smells

If same smell is detected for a period of time, body adapts to smell and no longer notice it Ex: perfume or cologne you are wearing, chemicals working with (fingernail salons), etc.

Many smells linked to memories - mamillary body

SENSE OF TASTE - GUSTATION PAPILLAE – bumps on the tongue TASTE BUDS – inside the papillae 4 main tastes: sweet, salty, sour, bitter

Substance dissolves and fits into a taste bud receptor. Action potential starts and sends message through facial or glossopharyngeal nerves to parietal lobe of cerebrum Brain interprets the taste Can detect about 5,000 diff. tastes

Hot and spicy foods actually stimulate pain receptors Smells of foods can cause stimulation of saliva Bitter taste is actually a protection – most spoiled or toxic foods are bitter Our genes determine the number and types of taste buds we have…that is why some people think certain foods taste good and some don’t EX: PTC paper

Odor from the foods both before and as you chew it influence taste

TODAY’S LAB