Question

the enamel on our teeth is the hardest substance in our body chemically it is calcium phosphate which is insoluble in water however if we eat too much of sweets or sugary food or we do not brush our teeth in the morning and before bed time a decay of tooth starts .what values are expressed in the above paragraph

Answer 1

When the PH of mouth is lower than 5.5 then tooth decay start.
value expressed by the paragraph is the person don't take care of his teeth. He have to brush twice in a day .

Answer 2

Due to decrease in the pH value of our mouth i.e. 5.5 when it decrease then due to increase in acidity or environment of our mouth become acidic which results in decaying of sugar molecules in our mouth which later accumulate on our teeth and then tooth decay starts.