2. Question from last lesson
Santa woke up and went to the fridge to get a glass of beer.
After pouring the beer into a glass and taking a gulp, he
immediately spit it back out as it had gone bad.
Using your knowledge of the 3 steps involved in gustatory
sensation, identify each stage and explain how Santa was
able to recognise that the milk had gone bad (6 marks).
3. Question from last lesson
Sample response:
RECEPTION: Molecules found in food are dissolved by saliva, allowing the
chemicals to stimulate taste buds.
TRANSDUCTION: The chemical energy is converted by the receptor cells on
the taste buds in into electrochemical nerve impulses that can be processed
by the brain.
TRANSMISSION: The electrochemical message is then sent from tastebud in
the form of electrical impulses to the brain.
Correct identification of the three stages of sensation = 1
mark per stage
Correct description of the role of each stage of gustatory
sensation, with reference to the scenario = 1mark per stage
4. Age
Research also shows that children are much more
responsive to taste than adults. One explanation is that they
have more taste receptors than adults. We start to lose taste
buds as we age, but exactly how many and when remain
unclear.
5. Genetics
For example, variants of one gene
(called TAS2R38) have been found to
in influence how strongly an individual
will be able to detect bitter tastes,
which may explain why some people
refuse to eat broccoli, Brussels
sprouts and similar dark green, leafy
vegetables throughout their lives.
Genetic differences make us more or less sensitive to the
chemical molecules in different foods
6. Perceptual Set
The taste we experience is shaped by our perceptual set.
This means that we often taste what we expect to taste.
When tasting pink soft drink is
changed to yellow with a neutral
food dye, it is reported as losing its
sweetness despite no real change
in its original taste properties
7. Culture
Cultural in influences on taste
appear to be determined
early in life, perhaps even in
the uterus. Research
suggests, for example, that
mothers can pass their food
preferences on to their
offspring during the months
immediately before (via
amniotic fluid) and after birth
(via breast milk).
