3. Dhruv is fond of eating idlis made of rice for
dinner. He developed dental caries even when he
brushed his teeth every morning.
a. Trace the various steps of the idli's digestion
from the time it is placed in the mouth to the
time it reaches the small intestine.
b. What could be the possible reason of dental
caries?
c. If you were Dhruv's friend, what you will advise
him to prevent dental caries?
Answers
a.idli is chewed with the help of teeth and salivary glands secrete saliva which is mixed with the help of tongue and the food is pushed to the oesophagus.it passes the food to the stomach where various digestive juices are secreted and mixed with the food.then, it is pushed to the small intestine where nutrients are absorbed.then pushed to large intestine to absorb extra water and then stored in the rectum for a few hours and eliminated by the anus.
b.dhruv brushes only in the morning.When he chews idli, the particles get stucked in the gap between his teeth.The germs present on teeth changes the food into acid which harms the teeth and cause tooth decay.
c.If i would be Dhruv's friend, I will advise him to brush both in the morning and at night.