Smell and Taste

Important roles of smell

1. Behavior(sexual, fear, disgust)

2. Identification

3. Memory

4. Appetite

Olfaction is a chemical sense. If the material being diluted is ___ soluble there is _____

1. Not

2. No odor

The CNS can adapt to certain ___ odors(i.e. it can no longer detect the odor - _____)

1. Constant

2. Accommodation

This allows the CNS to _____

Tend or respond to more important stimuli

Each smell gene encodes ____

Unique receptor protein

Protein responds to ____

One or more odors

Each odor binds to ____

Several different receptors

Each receptor has one type of _____

Receptor protein

______ receptors are also in nasal cavaties

Pain and temperature

Gaseous odorant must dissolve in _______

Fluid of olfactory ephithelium

Dissolved odorants bind to ____ in olfactory cilium membranes

Receptor proteins

If one sniffs an order for a long time, why is it difficult to detect?

1. Sniffing dries out the conchae

2. No solution

3. No odor detected

In lower animals olfaction is:

1. A matter of life or death

2. A part of sexual behavior

3. A part of reproduction

In humans, visual pictures and olfaction can ____

Affect appetite

Taste is a ____

Chemical phenomena

The substance detected must be in solution otherwise its ____

Tasteless

Some tastes are ___

Genetic

Taste can be affected by ____

Certain odors

Taste is ____% smell

80

Sense of taste is determined by the distribution of specialized ____

Taste buds(cells)

The four modalities are:

1. Sweet

2. Sour

3. Salty

4. Bitterness

5. Umami(deliciousness)

Some substances are salty probably due to the ____ effects on specific cells

[Na^+]

Since most ____ are ____ then it probably has to do with ____

1. Acids

2. Sour

3. [H^+]

Some substances if ___ are sweet

Diluted

Some substances if ____ are bitter

Concentrated

Unique receptors for sweet, bitter, and and umami coupled to ____

G protein gustducin

Cranial nerves VII and IX carry impulses from taste buds to ____

solitary nucleus of medulla

Impulses then travel to ____

Thamalus

From thamalus fibers branch to ____

Gustatory cortex in the ínsula

Vagus nerve transmits from ____

Epiglottis and lower pharynx