10. TASTE

Question 1

1. What is another term for “taste”?

Answer 1

• gustation

Question 2

2. What happens when someone chews their food?

Answer 2

• air is forced up your nasal passages
• the olfactory receptor cells register information at the same time as the taste receptors
• this allows us to taste and smell at the same time

Question 3

3. What body parts sort out the sensory information that is received when food is taken in?

Answer 3

• tens of thousands of taste buds
• these cover the tongue, the mouth and the upper throat

Question 4

4. What are the five groups of taste sensations?

Answer 4

• sweet
• salty
• sour
• bitter
• umami
  (corresponding to the flavour of glutamates)
  (GLUTAMATES= a salt or ester of glumatic acid)

Question 5

5. Are there assigned areas of the tongue that detect these tastes?

Answer 5

• no
• sensitivity variations around the tongue are insignificant
• tastes are registered on all parts of the tongue

Question 6

6. Where are the taste buds on the tongue located?

Answer 6

• they are tucked into tiny pockets
• these are hidden behind the stratified squamos epithelial cells on the tongue

Question 7

7. How many receptors does each taste bud have?

Answer 7

• 50 to 100 taste receptor epithelial cells
• they register and respond to different molecules in the food
• these are called specialised epithelial cells

Question 8

8. What are these specialised epithelial cells?

Answer 8

• they are synapse to sensory neurons
• they carry information about the type and the amount of taste
• they carry this information back to the brain

Question 9

9. What is necessary in order to taste any food?
   What happens as a result of this?

Answer 9

• the food chemicals (tastants) must dissolve in the saliva
• this is so that they can diffuse through taste pores
• they then go on to bind to receptors on the gustatory cells
• this triggers an action potential

Question 10

10. Is each tastant sensed differently?

Answer 10

• yes

Question 11

11. What are salty foods filled with?
    What does this lead to?

Answer 11

• they are filled with positively-charged sodium ions
• this causes sodium channels in the gustatory cells to open
• this generates a graded potential
• this sparks an action potential

Question 12

12. What are sour foods high in?

Answer 12

• hydrogen ions
• this makes them take a different route

Question 13

13. What are taste and all our other senses about?

Answer 13

• they are all about how action potentials get triggered

Question 14

14. What happens once the action potential is activated?

Answer 14

• the taste message is relayed through the neurons
• this is done via the seventh, ninth and tenth cranial nerves
• this message is taken to the taste area of the cerebral cortex
• this is the point of the brain that makes sense of all this information

Question 15

15. What happens once the taste message is relayed to the taste area of the cerebral cortex?

Answer 15

• the taste area of the cerebral cortex begins releasing digestive enzymes in the saliva
• it also releases gastric juices in the stomach
• this helps the breakdown of food