You will need the information in this file to complete the twolab sequence

This is the file that contains the report page for Lab 13-Taste,part 1

There are two things for you to turn in

Enter your taste data on the following page. You should all beable to edit and save the page.

Lab #13 - Taste Data W18

Taste Background

Background

Introduction

Taste is the least understood of all the senses. (PBS, 2000)Taste has been difficult to study because the receptors are notgrouped in one restricted place, as they are in the retina of theeye and the organ of Corti in the Cochlea of the ear. Also, thenerves that pick up the taste signal go to various different partsof the brain, unlike those of the eye, ear and nose. In additionbecause the mouth is a very damp environment, taste moleculesquickly diffuse to different places in the mouth so it is difficultto tell exactly what taste receptor is picking up the signal. Thiscomplexity lead to the incorrect idea that different kinds offlavors are picked up in only isolated parts of the tongue. Thetruth is that the receptors for all the different kinds of flavorsare all over the tongue, part of the soft palate and a short waydown the esophagus.

There are five types of taste receptors, those for salt, sweet,bitter, umami and sour. There is only one type of sour taste budand they detect acids (hydrogen ions or H+). There is only one typeof salt taste bud (detect sodium ions, Na+) and only one type ofsweet taste bud (detects sugar). Every normal person has all threeof these types of taste buds. In addition there are at least threedifferent kinds of Umami receptors and many different kinds ofbitter taste buds and not everyone has the same types. (Westbrook,2009) There is a huge amount of genetic diversity in the humanability to taste. (Westbrook, 2009)

Genetics

“There is scientific evidence that supports the hypothesis thatthere is a genetic basis for food preferences. The genes have beenfound for salt sweet and sour and several have been found for umamiand bitter taste receptors. In particular, one bitter receptordetects a compound called PTC. The ability to taste this compoundis carried by one allele (dominant - B) for this gene and the otherpossible allele (b) codes for a non-functional receptor. Someonewith the genotype bb cannot taste PTC, with genotype Bb can tastePTC and with genotype BB can taste PTC really well. The PTC-tastingallele is about as common as the non-taster allele. (Westbrook,2009) Supertasters have a rare allele on a different gene thatincreases the intensity of many tastes, not just PTC. (Westbrook,2009)

Supertasters

A supertaster is a person whose sense of taste is significantlymore sensitive than average. The cause of this heightened responseis thought to be, at least in part, due to an increased number offungiform papillae (a type of tastebud – See the section below onAnatomy). (Baroshuk, 1994) (Wikipedia)

Each of us is born with a genetically determined number of tastebuds. People can be divided into three groups: supertasters (25% ofthe population), medium tasters (50%) and non-tasters (25%).Supertasters have many more taste buds per square centimeter(thousands per square inch) than medium tasters or non-tasters (afew hundred total). Evidence suggests that supertasters are moresensitive to bitter tastes and fattiness in food, and often showlower acceptance of foods that are high in these taste qualities.Supertasters tend to dislike strong, bitter foods like rawbroccoli, grapefruit juice, coffee and dark chocolate. (TheSupertaster Test) Supertasters also seem to experience thetemperature and texture of foods more keenly than medium tastersand non-tasters. (PBS, 2000)

Some people have speculated that there might be advantages ordisadvantages to being a supertaster based on the environment.(PBS, 2000)

Evolution

Taste receptors probably evolved to help us detect good andpotentially bad things in our food. Good things (or those thatplease us) include sugar, salt, and protein and we have specificreceptors or pairs of receptors to detect these. Sourness (acidity)can be a sign that otherwise good food has spoiled, and oftenbitter taste is associated with plant material that is poisonous.(23andme) To protect themselves animals can run away or fight.Plants have the same kind of evolutionary need to protectthemselves as we do. A plant can make thorns or poisonous chemicalsto deter animals from eating it. The poisonous compounds in plantshave many different structures. Our sense of taste can help protectus from these poisons so it isn’t surprising that the family ofbitter taste genes encodes at least 25 different receptors.(23andme)

PTC, which we will be testing in this lab, is a very bittercompound, and those who can taste it will usually dislike theflavor. Since bitter compounds are found in vegetables likebroccoli, cabbage, turnips, and kale, people who can taste PTCusually don’t like their veggies. (Westbrook, 2009)

Advantages and Disadvantages to being a Supertaster

Advantages: During evolution, supertasters would have had anadvantage in environments with lots of poisonous plants with bittertastes. The supertasters would have perceived the greatestbitterness and thus would have been the most likely to avoid theplants. (PBS, 2000) (F. D. Kitchin, 1959 April 25: 1069-1074)

Disadvantages: PTC tasters are less likely to eat vegetablesbecause many of them have a bitter taste. Some bitter tasting foodscontain phytochemicals which are actually healthy to eat (e.g.,protect against cancer). Supertasters might like these foods less,eat fewer of them, and suffer from diseases that those foods mighthave prevented. Supertasters perceive the most intense sensationsfrom salt, acids, and sweeteners as well as from fats in foods.Thus one's ability to taste PTC may turn out to be important to avariety of health problems where diet plays a role. (PBS, 2000)(Richter, 1942) (Westbrook, 2009)

Advantages and Disadvantages to being a non-taster

Advantages: In an environment with bitter plants that are notpoisonous, the non-tasters have the advantage because they have abigger food world.

Disadvantages: People who cannot taste PTC tend to ingest moreof similar compounds. One example of a natural compound similar toPTC is a chemical found in turnips and cabbage. (Brussels sproutsare a kind of cabbage.) Although cabbage is not generally toxic,eating a lot of it sometimes causes goiter, a condition in whichpeople have swollen, sometimes enormous, glands in their neck.Goiter is often caused by a lack of iodine in the diet, and todayit is found mostly in places where diet is poor and iodized tablesalt is not widely available. The PTC-like chemical in cabbagemakes goiter more likely to occur by blocking the body fromabsorbing whatever iodine is in the diet. (23andme) (Westbrook,2009)

Anatomy

Humans receive tastes through sensory organs called taste buds(gustatory calyculi) concentrated on the upper surface of thetongue. (Wikipedia) In most animals, including humans, taste budsare most prevalent on small pegs of epithelium on the tongue calledpapillae. The taste buds themselves are too small to see without amicroscope, but papillae are readily observed by close inspectionof the tongue's surface. (The Supertaster Test)

Each fungiform papillae (the mushroom-shaped structures on thetip of your tongue) contains about a half dozen taste buds. Otherbumps on the tongue are different kinds of papillae that do notcontain taste buds. (PBS, 2000)

Tongue

(The Supertaster Test)

Semidiagrammatic view of a portion of the mucous membrane of thetongue. Two fungiform papillæ are shown. On some of the filiformpapillæ the epithelial prolongations stand erect, in one they arespread out, and in three they are folded in.

(Gray, 2a. The Mouth, 1918)

Taste buds are composed of groups of between 50 and 150 columnartaste receptor cells bundled together like a cluster of bananas.The taste receptor cells within a bud are arranged such that theirtips form a small taste pore, and through this pore extendmicrovilli from the taste cells. The microvilli of the taste cellsbear taste receptors. (Bowen, 2006)

(Sensory Organs, 2009)

(Bowen, 2006)

(Wikipedia)

Part 1 – Count the number of Papillae you have in a given areaof the top of your tongue.

1. Chew a small piece of the blue or green colored candyincluded in your lab kit or rub the blue lollipop on the yourtongue to color it blue. The tiny bumps (the fungiform papillae) onyour tongue that house your taste buds don't take up food coloringvery well. These are the pink, or light colored spots you see. Themore papillae you have, the more taste buds you have and the moresensitive to taste you are.

2. Place one of the reinforcing rings for a three ring bindernear the front of your tongue. On average, non-tasters have fewerthan 15 papillae in that area, while supertasters have over 25.(23andme) (Test Your Tastebuds)

3. Count the pink/light colored dots within the reinforcementring. This may be easier with a magnifying glass. You can use themagnifier from lab #1 – Observation. Enter this information intoData Table 1 at the end of the lab.

(Test Your Tastebuds)

(Bowen, 2006)

(PBS, 2000)

Figure 1 Taste buds of Tasters and Non-Tasters.

Part 2 - What molecules do you taste?

As you do this part of the lab, keep in mind the number ofpapillae you recorded. If you have more than 25 papillae in thetest circle be prepared to be a super taster and test a tiny bit ofthe test paper at first. The candy included in the lab kit is verysour, which should help cover the bitter taste of PTC if it isoverwhelming.

Bibliography

   •   23andme. (n.d.). Bitter TastePerception. Retrieved August 20, 2011, fromhttps://www.23andme.com/health/Bitter-Taste-Perception/howitworks/

   •   Baroshuk, L. V. (1994, 56(6)).PTC/PROP tasting: anatomy, psychophysics, and sex effects.Physiol Behav , pp. 1165-71.

   •   Bowen, R. (2006, December 10).Physiology of Taste. Retrieved October 31, 2011, fromhttp://www.vivo.colostate.edu/hbooks/pathphys/digestion/pregastric/taste.html

   •   Caruso, D. W. (n.d.). What Do YouTast? Retrieved 2011

   •   Chudler. (n.d.). Bitter.Retrieved fromhttp://faculty.washington.edu/chudler/bitter.html

   •   F. D. Kitchin, W. H.-E. (1959 April25: 1069-1074, April 25 :1(5129):). P.T.C. Taste Response andThyroid Disease. pp. 1069-1074.

   •   Fox, A. L. (1932). The Relationshipbetween Chemical Constitution and Taste. In A. L. Fox,Genetics (pp. 115-116). Wilmington, Delaware: JacksonLaboratory, E.I. Du Pont de Nemours & Co.

   •   Gray, H. (1918). 2a. The Mouth. In H.Gray, Anatomy of the Human Body (p. figure 1018 paragraph84). Bartleby.com.

   •   Gray, H. (1918). 2a. The Mouth. In H.Gray, Anatomy of the Human Body (p. fig 1014 paragraph80). Bartleby.com.

   •   Lindemann, B. (2000). A taste forUmami taste. Nature Neuroscience 3 (2) , pp. 99-100.

   •   NIH. (n.d.). Retrieved fromhttp://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=OMIM&dopt=Detailed&tmpl=dispomimTemplate&list_uids=171200

   •   PBS. (n.d.). Peppers.Retrieved August 2011, from Life's Little Questions: Why ArePeppers Hot? :http://www.pbs.org/safarchive/3_ask/archive/qna/3294_peppers.html

   •   PBS. (2000). ScienceFrontiers. Retrieved August 13, 2011, fromhttp://www.pbs.org/safarchive/4_class/45_pguides/pguide_904/4494_peppers.html#act2

   •   Pennsylvania, U. o. (1994). RetrievedAugust 12, 2011, fromoncolink.upenn.edu/cancer_news/1994/hot_candy.html.

   •   Relative Chili Heat. (n.d.).Retrieved August 12, 2011, fromwww.wiw.org/~corey/chile/scoville.html

   •   Richter, C. a. (1942). Arch.Path. , pp. 33, 46.

   •   Sensory Organs. (2009,March). Retrieved November 16, 2011, from Aurthurs Clipart:http://www.arthursclipart.org/medical/senseorgans/taste%20buds%202.gif

   •   Test Your Tastebuds. (n.d.).Retrieved August 20, 2011, fromhttp://www.bbc.co.uk/science/humanbody/body/articles/senses/tongue_experiment.shtml

   •   The Supertaster Test. (n.d.).Retrieved August 23, 2011, from http://supertastertest.com

   •   Westbrook, D. a. (2009, January 9).What Do You Taste? Retrieved November 18, 2011, fromSPICE: www.spice.centers.ufl.edu/mendelian genetics/deena lesson1.doc

   •   Wikipedia. (n.d.). Retrieved November6, 2011, from http://en.sikipedia.org/wiki/taste

13 – Taste Lab, Part One – Collecting the data

There are three sections to this part of the taste lab. The firstis to count the number of taste papillae inside a small circle. Thesecond is to determine if you are a taster non-taster orsupertaster of PTC. The third is to record your data in theeditable file in the taste lab assignment page.

The hypothesis we are testing in the two labs,“13-Taste Lab, Part One” and “13-Taste Lab, Part Two” is: “The morepapillae you have (which means more taste buds you have) the moresensitive to taste you are.” In particular we are testing thestatements in “23andme” and “Test your Tastebuds” (see thereference list in the background file) that in the front part ofthe tongue, on average, non-tasters have fewer than 15 papillaewhile supertasters have over 25.

Section 1 – Count the number of Papillae you have in a givenarea of the top of your tongue.

(Test Your Tastebuds)

(Bowen, 2006) (PBS, 2000) (PBS, 2000)

   Figure 1 Taste buds of Tasters and Non-Tasters

Procedure

   •   Rub the blue lollipop (or dum-dum)that is included in your lab kit on your tongue to color it blue.The tiny bumps (the fungiform papillae) on your tongue that houseyour taste buds don't take up food coloring very well. These arethe pink, or light colored spots you see.

   •   Place one of the reinforcing ringsfor a three ring binder near the front of your tongue.

   •   Count the pink/light colored dotswithin the reinforcement ring. This may be easier with a magnifyingglass. You can use the magnifier from lab #1 – Observation. Enterthis information into Data Table 1 at the end ofthe lab.

Section 2 - What kind of taster are you?

As you do this part of the lab, keep in mind the number ofpapillae you recorded. If you have more than 25 papillae in thetest circle be prepared to be a super taster and test a tiny bit ofthe test paper at first. There is sour candy included in the labkit which should help cover the bitter taste of PTC if it isoverwhelming.

Procedure

   •   Take half of one control taste teststrip. Place half the taste strip on your tongue. Record inTable 1 what the test strip tastes like to you.You probably won’t taste anything but if you do, it should tastelike paper.

   •   Take half of one PTC taste teststrip. Place the half taste strip on your tongue. Check the box inTable 1 that describes how intense the flavor wasto you (super taster, taster or non-taster). If you tasted nothing,or if it tasted the same as the control test, you are a non-taster.Otherwise, you are a taster. You are a super taster if you canbarely stand the flavor. Your lab kit should contain some kind ofsour candy which will help get rid of the taste.

Section 3 – Record your data

Make sure your own data is recorded here in table 1 and on theeditable “Canvas page” for Lab #13 – Taste Data.

Suggestion:

When you are finished you may have some of the taste stripsleft. You can use them to test other members of your family and/orfriends.

13 – Taste, Part 1   Lab Report Page  Name   

Specifics for the lab

There are three types of data we will collect in this lab;number of taste buds, taste of the control paper, taste of the PTCpaper.

   1) Count and record in table 1 the number of tastebuds you have in a given area on your tongue.

   2) Record your taste sensation for the controlpaper in table 1.

   3) Record in Table 1 whether you are a non-taster,taster or supertaster of PTC.

   4) Enter your taste bud count and what kindof taster you are for PTC in the editable “Canvas page” for Lab #13– Taste Data.

The class data will be used in 13-Taste, Part 2 - DataAnalysis.

Data Table 1

Papillae count Control paper taste PTC (check one box)

   Non-taster taster Super taster

13 – Taste Lab, Part Two, Data Analysis

In 13 – Taste Lab, Part 1 We collected data from everyone in classfor number of papillae and type of taster of PTC. This purpose ofthis part of the lab is to analyze that data.

The hypothesis we are testing in the two labs, “13-Taste Lab,Part One” and “13-Taste Lab, Part Two” is: “The more papillae youhave (which means more taste buds you have) the more sensitive totaste you are.” In particular we are testing the statements in“23andme” and “Test your Tastebuds” (see the reference list in thebackground file) that in the front part of the tongue, on average,non-tasters have fewer than 15 papillae while supertasters haveover 25.

There are three sections to this part of the taste lab. Thefirst is to record and organize the class data. The second is tograph the data in a way that will help you see if there is acorrelation between number of taste papillae and type of taster.The thirds is to write a conclusion to this lab. A conclusion is aneffort to describe what your analyzed data shows and describewhether or not the hypothesis is supported by our data. You alsoexplain what type of experiments can be done to confirm yourconclusion.

One example of how to record and analyze the data

Table 1 is the data from the last quarter class. I have left offthe names of everyone and you may do the same. To make it easierfor me I have color coded each line for how many taste buds thatperson has. We will be using three categories, 0-15, 16-24 and morethan 25. The colors I used are in table 2. You don’t need to usethese colors or this way of analyzing the data.

In Table 1 each type of taster is assigned a value. Non-tastersare labeled “0”, Tasters are labeled “1” and super tasters arelabeled “2”.

It is unlikely that our data will give a perfect correlationbetween papillae count and type of taster so I have made anothertable, Table 3, which has the columns labeled by number of papillaeand the rows are for the type of taster that person is. Columns A,B and C don’t really go together. At the bottom of the table thetype of taster is averaged for each type of papillae count.

To read this table, for example, for A the type of taster is0.6. Less than a taster but more than a non-taster.

Figure 1 is an example of one way you can show a graphicalrelationship between papillae count and type of taster. Thisparticular set of Data shows a good correlation between papillaecount and type of taster.

Report Page   Name  

Data Analysis

   1) Collect the data from everyone in the class. Thedata should be taken directly from the data file on the assignmentpage in Canvas. You may copy and paste it here or type out your ownversion. The form should look like Table 1 above (like this).

Data Table

Papillae count	Non-Taster	Taster	Super-Taster

.

.

.

2)   Reorganize your data into something that willhelp you analyze the data (for example, like Table 3).

3)   Present some kind of graphical representation ofthe data.

4)   Restate the hypothesis and write a conclusion tothis experiment.

5)    Answer the questions at the end of the lab

Questions

   1. What (if any) correlation do you see between thenumber of papillae you have and the type of taster you are? (Give ashort version of your conclusion).

   2. What can you say about the number of taste budssomeone has relative to the number of papillae?

   3. Describe a possible evolutionary advantage tobeing a

A) supertaster -- for animals and humans.

B) non- taster -- for animals and humans.

4. What factors other than number of taste buds might explain aperson's food preferences?

Enter your taste bud count and check the box corresponding towhether you are a non-taster, taster or Super taster.