This question was poorly attempted by most of the candidates that answered it. In
question 8(a), some of the candidates could not draw and label the digestive system of a
ruminant animal. Further to this, most of the candidates were unable to describe the
process of digestion in the ruminant animal as demanded in question 8(b).
The expected answer include:
Digestive system of a ruminant animal
Diagram:
Oesophagus
Title
Scale/accuracy
Labeling
Description of the process of digestion in the ruminant animal
- The food material (grasses in most cases) is gathered into the mouth with the aid of the
tongue and griped by the teeth on the lower jaw
- The grass passes through the oesophagus and enters the first stomach, or rumen,
where digestion of cellulose by bacteria takes place;
- By anti-peristaltic movement of the stomach, the undigested grass or cud passes from
the rumen to the reticulum from where it re-enters the oesophagus and finally gets
back to the mouth;
- The cud is then chewed for a time with the molars in a semi-liquid cud and it is then
swallowed into the third chamber, called the manyplies or omasum; from where it
passes to the last chamber, the abomasum where gastric juice is secreted into the
semi-digested food called chyme. This chyme then passes through the duodenum into
the small intestine where complete digestion and absorption of the nutrients take
place.
- The undigested material passes into the large intestine where further absorption of
water takes place and then finally passes to the ceacum and rectum and finally voided
through the anus.
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