Digestion and Absorption Test - 68

pH scale is not a linear scale like a centimetre or inch scale (in which two adjacent values have the same difference). It is a logarithmic scale in which two adjacent values increase or decrease by a factor of 10. As pH 7.5 and 5.5 differ by 2, the difference in H$$^{+}$$ ion concentration between them would be 10$$^{2}$$ = 100.

The optimum pH for the enzymatic activity of salivary amylase ranges from 6 to 7. Above and below this range, the reaction rate reduces as enzymes get denaturated. The enzyme salivary amylase is most active at pH 6.8. 

The major contributor to plasma ammonia is the intestine. Intestinal ammonia is derived via two major mechanisms. First, ammonia is liberated from urea in the intestinal lumen by enzymes known as ureases. Ureases are products of many bacteria and convert urea to ammonia and carbon dioxide. Second, after proteins are digested by either host or bacterial proteases, the further breakdown of amino acids generates free ammonia.

• Appendix is present at the junction of small intestine and large intestine just before the cecum.
  
• It is a thin tube four inches long.

The appendix is a tubular structure present at the junction of the small and large intestine. It is present on the base of the cecum on the large intestine.

A form of amylase found in the saliva of humans and some other animals is called Ptyline. It digests the raw starch.

 In kwashiorkor, there is a decrease in the human serum albumin levels. This decrease leads to a deficiency in the protein levels of an individual. This causes accumulation of fluids in the tissue which further causes swelling. This swelling is most common in the abdominal region. The swelling can mainly be attributed to the retention of water in the blood plasma by the osmotic pressure created because of the decreased number of albumins and globulins.

So, the correct answer is 'Albumin and globulins retain water in the blood plasma by their osmotic effects'.

Pepsin is an enzyme produced in the mucosal lining of the stomach that acts to degrade protein. Pepsin is one of three principal protein-degrading or proteolytic, enzymes in the digestive system, the other two being chymotrypsin and trypsin ( secreted in the small intestine). Optimum pH for pepsin is 1.5-1.6. 

Salivary glands in your mouth (Buccal cavity) make salivary amylase, which begins the digestive process by breaking down starch when you chew your food, converting it into maltose, a smaller carbohydrate.

• The oesophagus is a hollow distensible muscular part of the alimentary canal.
• The ability to stretch and expand is called distensibility.
• The distensibility of the oesophagus allows any kind of food to pass through it with ease.
• The oesophagus dilates and propels the food from the region of the pharynx to the stomach.
• The stomach is a J shaped distensible bag like structure and is a highly distensible part of the alimentary canal.
• It may take varying shapes and can hold about 1 litre of food.
• The gastric folds in the inner walls of the stomach allow it to get expanded.
• So, the correct answer is 'Stomach'.