Rayat Shikshan Sanstha , Karmveer Vidhyaprabhodhini Madhya Vibhag ,Satara

Std. 7 th

Sub. Science

Unit - 13. FOOD AND NUTRITION

Standard :- 7th

Subject :- Science

13. FOOD AND NUTRITION

FOOD AND NUTRITION

1. Parts of The Alimentary Canal

The alimentary canal (or gut) is the tube within the body through which food passes and is processed in various ways

2. Role of the Mouth

Salivary gland

Salivary gland

Salivary gland

Saliva is mixed with food during chewing

Teeth assist the mechanical breakdown of food

Saliva contains the enzyme amylase which starts the digestion of food

Saliva contains mucus that keeps the mouth moist and lubricates food for easier swallowing

3. Muscles of the Alimentary Canal

• Food has to be kept moving along the alimentary canal whilst being mixed with various juices

• These actions are brought about by muscles in the walls of the canal over which a person has little or no conscious control

Digestion‘the breakdown of large insoluble molecules into soluble molecules’

Digestion and Digestive Juices

Saliva

PANCREATIC JUICE

GASTRIC JUICEBile

INTESTINAL JUICE

Sites of production of main digestive juices

Site of digestive juice production

Main digestive juice produced

Mouth Saliva

Stomach Gastric juice

Liver Bile (breaks down big fat droplets into little fat droplets

Pancreas Pancreatic juice

Small Intestine Intestinal juice

Digestion and Digestive Juices

SALIVA

•Salivary amylase

PANCREATIC JUICE

•Pancreatic lipase

GASTRIC JUICE

•Hydrochloric acid

•Pepsin (protease)

Bile

INTESTINAL JUICE

In the Mouth…

Starch maltose

• Broken down into glucose later by other amylases

Salivary amylase

In the stomach

Protein peptides

Broken down into amino acids later by other proteases

pepsin

In the pancreas….

Fats fatty acids and glycerolPancreatic lipase

After all the digestive enzymes have done their work…

• Glucose

• Amino acids

• Fatty acids

• Glycerol

Rayat Shikshan Sanstha , Karmveer Vidhyaprabhodhini Madhya Vibhag ,Satara

Std. 7 th

Sub. Science

Unit - 13. FOOD AND NUTRITION

• Created By –