SCIENCE 08 BIOLOGYNotebook Page E

EXPERIMENT # 2

TASTE RECEPTORS

PROBLEM:

To determine which areas of the tongue contain taste buds that primarily detect salty taste, bitter taste, sweet taste, and sour taste.

HYPOTHESIS:

Copy this statement: "The areas of the tongue that I predict will contain taste buds primarily able to detect each of the four tastes are indicated in Diagram I ".

(Instructions: On your diagram label regions predicted to be sensitive to each of the four tastes.)

APPARATUS AND MATERIALS:

4 Q-tipspaper cup

four taste samplesdrinking water

PROCEDURE:

1.Obtain 4 Q-tips and a paper cup for drinking water. Use only one Q-tip at each taste station, then for sanitary reasons immediately dispose of it properly in the garbage container. Also dispose of the paper cup when finished the experiment.

2.There are four taste stations labelled "A", "B", "C", and "D". Go to one of these stations.

3.Dip your Q-tip into the solution ONLY ONCE. Touch this Q-tip to your tongue in the areas shown in the diagram below:

CAUTION: TOUCH EACH AREA QUICKLY AND GENTLY ONLY ONCE ! DO NOT SPREAD THE CHEMICALS ALL OVER YOUR TONGUE. THIS WILL DULL YOUR SENSE OF TASTE. SWALLOW THE CHEMICALS AFTER TASTING; DO NOT SPIT THEM OUT !

NEVER PLACE YOUR USED Q-TIP BACK INTO ANY SOLUTION.

4.Decide which taste region is most sensitive to the chemical you have tried. In your observations label in Diagram II the letter representing this chemical in this region.

5.Decide whether the chemical you tasted was salty, sweet, sour, or bitter. In your observations label in Diagram II the type of taste in this region.

6.After swallowing clean your taste buds by taking a sip of water, thoroughly swishing it around your mouth, and swallowing.

7.Repeat procedures 3 to 6 for each of the other taste stations.

 

 

 

EXPERIMENT #2: TASTE RECEPTORS PAGE 2Notebook Page E

OBSERVATIONS:

Copy the following statement: "Refer to Diagram II".

(Instructions: As indicated in the procedure label Diagram II with the following information:

1.The "letter" of the chemical at the taste station to which each area of the tongue was most sensitive.

2.The name of the type of taste associated with each chemical.

DISCUSSION:Answer the following questions in complete sentences.

1.Did your tongue taste all of the chemicals in all of the areas equally well ?

2.Rank the four tastes in order of the ease of detection from easiest to most difficult to detect.

3.Of the four tastes which one is usually not associated with food we normally eat ?

4.Why is it important to detect this taste (from #3) if it is not normally associated with food ?

5.What other sense besides taste has sensory receptors on the tongue ?

6.What two qualities associated with food besides taste are detected by these receptors (from #5) ?

CONCLUSION:

1.Make a judgment statement concerning your hypothesis being certain to specifically state the correctness of each of your four predictions.

2.Using such terms (or combinations) as "tip, front, side, back, middle" state in words the regions of the tongue associated with each type of taste as follows:

eg."The taste buds for sweet are located mainly on the of the tongue, for salty are located mainly on the , etc. ---

3.Copy or trace the following diagrams onto your looseleaf paper labelling each with the taste associated with the shaded region of the tongue.

FIGURE 1FIGURE 2FIGURE 3FIGURE 4

 

 

 

 

 

 

REGION #1REGION # 2REGION #3REGION #4

TASTETASTETASTETASTE

EXPERIMENT #2: TASTE RECEPTORSNotebook Page E