The document discusses the constituents of a balanced diet and the process of digestion. It lists the essential components of a diet as carbohydrates, proteins, fats, vitamins, minerals, water, and fiber. It then describes the role of the mouth, esophagus, stomach, small intestine, large intestine, liver, gallbladder, and pancreas in breaking down and absorbing food. The liver produces bile to help digest fats and filters toxins from the bloodstream, while the gallbladder stores and releases bile and the pancreas produces enzymes to digest nutrients and regulates blood sugar.

1. CONSTITUENTS OF DIET
The essentials of our ‘diet’ are;
1 carbohydrates
2 proteins
3 fats/oils
4 vitamins
5 minerals
6 water
7 fibre
All these present in our ‘diet’ in the right amount make it a
‘balanced diet’.

2. PATTERN OF NUTRITION

3. INGESTION AND ROLE OF MOUTH
In our mouth food is broken into smaller
pieces by teeth. This is also known as the
‘mechanical break down’ of food.
Once the food is crushed, saliva mixes
with food and makes it soft. ‘Amylase’ in
the saliva acts on it and chemical action
begins.

4. ALIMENTARY CANAL
Oesophagus secrete mucus. This mixes
with the food and a bolus is formed. Due
to muscular contraction ‘bolus’ moves
down into the stomach. The process is
peristalsis.
Food is pushed into stomach. Here it
mixes with digestive juices which
contain enzymes. Due to chemical action
of these enzymes it is further broken
down.
Acid in the stomach kills bacteria.
Food in the stomach is called chyme.

5. SMALL INTESTINE
Lining of intestine walls has finger like
projections called villi.
Nutrients from the food pass into the
bloodstream through the small intestine
walls.

6. LARGE INTESTINE
Large intestine absorbs all what small
intestine does not absorb
Rectum stores the waste material for a short
while. This is then expelled out. It is known as
feces. Water from the feces is absorbed and
retained in the body.

7. ROLE OF LIVER, GALLBLADDER &
PANCREAS IN DIGESTION
Liver produces bile. This helps digest fats.
It also filters toxins, waste material including
drugs.
Gallbladder stores bile from the liver, and
releases it into the small intestine.
Pancreas produces digestive enzymes to
digest fats, carbohydrates and proteins.
It also regulates blood sugar by producing
insulin.

8. DETAILED FUNCTIONS OF LIVER