Question

(a) Draw a diagram of human alimentary canal and label on it:
Oesophagus, Gall bladder, Liver and Pancreas
(b) Explain the statement, 'Bile does not contain any enzyme but it is essential for digestion.'

Answer 1

(a)

Human alimentary canal

(b) Bile does not contain any enzyme, but it plays an important role in digestion as it performs the following functions:

• The bile salts break down large fat globules into smaller globules so that the pancreatic enzymes can easily act on them. This is referred to as emulsification of fats.
• The food entering the small intestine is acidic which has to be made alkaline so that the pancreatic enzymes can act on it. This function is also performed by bile juice.