Question

Rama ate rajma and rice in her lunch. Explain the various steps by which the components in her food got digested.

Answer 1

Rajma contains protein and rice contains carbohydrates. While protein is digested in stomach and small intestine, carbohydrates are digested in mouth and small intestine.

The saliva consists of enzymes such as salivary amylase, electrolytes and lysozyme. Salivary amylase digests carbohydrates up to 30%. Digestion in stomach occurs due to gastric juice secretion containing hydrochloric acid, pepsinogen, lipase and renin.

Potein is digested by pepsin here while bicarbonate and mucus in stomach protects it from the acid by lubricating the gastric epithelium.

In small intestine digestive juices like bile, pancreatic juice and other juices secreted by the organ itself helps in digestion.

The three enzymes namely trypsin, lipase and amylase in prancreatic juice helps in digestion of food in the duodenum.

The partially digested food is passed in the second part where it is digested by enzymes like sucrase, lactase and maltese.

Answer 2

Rice is made of carbohydrate and rajma is rich in protein. This food also contains fats and oil.

The various steps by which the components in her food got digested is:

• The digestion process starts right from mouth, where the salivawith enzyme lysozyme and salivary amylase are secreted.
• The carbohydrate is digested by salivary amylase. Lysozyme acts on protein from rajma.
• In stomach Hydrochloric acid acts on both protein, carbohydrate and fats.  
• In stomach the enzyme pepsinogen acts on protein from rajma, which digests it further in to simpler units.
• The partially digested carbohydrate, protein and fats are acted upon by chyme, pancreatic juice, action of bile and digestive enzymes in small intestine and broken down in to final simpler form.