Human Body – Hands-On Experiments
Food Tasting – GENERAL INFORMATION
The sense of smell is an important factor in distinguishing tastes. Impared olfactory receptor cells or blocked nasal passages can cause us to lose our ability to distinguish tastes. Food must be moist for taste to occur. Although all taste receptor cells appear structurally the same, they connect to one of two different nerves associated with the tongue. Different characteristics of taste seem to be associated with different areas of the tongue but the actual mechanics of taste differentiation is not known. Taste impulses are sent through the thalamus in the brain stem to a specific area of the cerebral cortex where they are interpreted. Taste receptors are shed and replaced on the surface of the tongue about every 20 days.
Food Tasting – MATERIALS
Provide enough toothpicks so that each food taster has one for each food tasted. You’ll need to use one paper cup for each food tasted. Use a variety of foods as suggested on the student sheet. Instruct students to keep their eyes closed or provide a blindfold.
WORKSHEET & Sample PDF Activity
Sample PDF Activity
Food Tasting – PROCEDURE
Choose one or more food tasters from the class. Blindfold the first taster and have him/her hold the nose closed or use a nose clip. Using a toothpick, carefully place a bit of food on the taster’s tongue. Without chewing the food, have the taster identify it. Record the results on the chart. Repeat with the nostrils open, changing the order of foods sampled. Be sure to use different toothpicks each time.
Food Tasting – ANSWERS TO QUESTIONS
- Most will show that ‘nose open’ is more accurate
- Smell (as per the test), sight – discuss the importance of aesthetically-presented food, especially in advertising and restaurants.
- Answers will vary.
- Blocked or ‘stuffed-up ‘ nasal passages make tasting more difficult.
EXTENSION IDEAS
Thought Questions:
Q: Why do you suppose your nose is located on your face, near your eyes and mouth?
A: You are able to see what you are smelling before you eat it. If something looks and smells spoiled, you’ll know not to eat it.
Q: If your nose were located on your arm or leg, how would this affect you?
A: Your nose would be more susceptible to injury, and you wouldn’t be able to smell food before you ate it.
Q: A fly’s taste buds are located on its feet. What value is this to the fly?
A: A fly can taste potential food simply by landing on it. If the surface landed upon is not edible, the fly continues its search for food.
Food Tasting – You Will Need:
blindfold
paper cups
toothpicks
7 food samples (cut solids into small chunks)
apple, onion, peanut butter, catsup, mustard, etc.
Food Tasting – Here’s How
- Blindfold tester and have him/her hold the nose closed or use nose clips.
- Using a toothpick, carefully place a bit of food on the taster’s tongue and have him/her identify it. Record the results on the chart, “Y” if taster was able to identify food and “N” if not. Use a separate toothpick for each sample and for each taster. Rinse mouth after each taste.
- Repeat with nostrils open, but change the order of foods sampled.
Food Tasting – Questions
1 . Which test produced more accurate results?
- Which other sense, besides taste, plays a part in how foods taste to us?
- Were any foods identified under both conditions?
- How would having a cold affect tasting ability?
Table of Contents Life Science – Human Body – REM6526
SENSES & THE BRAIN
Food Tasting 1 – 2
Concept: Students will discover that the sense of smell plays a role in how foods taste.
Smelling Time 3 – 4
Concept: Students will discover that odor molecules move through the air at a certain rate.
Disappearing Dot 5-6
Concept: Students will discover that there is a “blind spot” on the retina where the organs of sight do not occur.
Black Flag 7 – 8
Concept: Students will discover that the over stimulation of color receptors on the retina will cause an afterimage of another color.
Catching an Orange 9 – 10
Concept: Students will discover that depth perception is aided by stereoscopic vision and that the brain can compensate for loss of stereoscopic vision.
Left or Right Sided? 11 – 12
Concept: Students will discover that humans have a dominant side that is stronger and faster than the other side.
HEART, LUNGS, BONES, & MUSCLES
Bendy Bones 13- 14
Concept: Students wil1 discover and demonstrate that minerals In bone contribute to its rigidity and can be chemically removed from bone.
Dancing Hairpin 15 – 16
Concept: Students will discover that muscles are always contracting, even when they appear still.
Exercise and Pulse Rate 17 – 18
Concept: Students will discover that exercise causes an increased pulse rate.
Chart Your Breathing Rate 19 – 20
Concept: Students will discover that their breathing rates vary throughout the day and are dependent on the amount of oxygen needed to perform different tasks.
Oxygen and Carbon Dioxide in Expired Air 21 – 22
Concept: Students will discover that expired air contains less oxygen and more carbon dioxide than ambient air.
Lung Model 23 – 24
Concept: Students will construct a mode/lung in order to demonstrate and understand that the diaphragm muscle creates the ability to breathe.
Digestion of Starch 25 – 26
Concept: Students will discover that starch is digested into sugar in the mouth by the action of the enzyme amalyase.
Evaporation Rate 27 – 28
Concept: students will discover that skin temperature is directly related to the evaporation rate of fluids from the skin.
The Perspiring Palm 29 – 30
Concept: Students will discover that sweat glands are concentrated on certain areas of the skin by locating a pattern of sweat glands on the palm of the hand.
