After chewing food the saliva covered mass that remains is called a bolus. This mass is easy to swallow and can move easily through the esophagus to the stomach. Chewing reduces the size of food and once it reaches the stomach it mixes with gastric acid which further breaks down food in the process of digestion.
As sugars the excess portion
Answer:
Option (3).
Explanation:
Teratogens may be defined as the chemicals that can cause birth defects in the fetus. Substances like alcohol, lead and nicotine acts as the main agents of tertaogens.
Shamona is drinking water that contains high level of lead. The element lead is harmful for the fetus. Even the small concentration of lead is enough to cause birth defects. The lead exposure can cause the abnormal development of brain and damages the brain of fetus. The fetus has low birth weight also.
Thus, the correct answer is option (3).