A cow is given some corn as part of its diet. The corn mostly contains complex carbohydrates like starch. What will happen to these carbohydrate molecules as they move through the cow's digestive system?

The corn is mixed with saliva in the mouth, travels through the oesophagus to the rumen where it is fermented by enzymes from microorganisms in the rumen and they are converted to acids which are absorbed from the wall of the rumen into the liver where they are used as a source of energy for the cow.

Explanation:

The digestion in cows differs from the digestion in humans.

Cows are know as RUMINANTS.

The digestive system in cows are divided into 5 parts.

a) The mouth

b) The oesophagus

c) The stomach, which is divided into 4 compartments:

i. Rumen

ii Recticulum

iii Omasum

iv Abomasum (“true stomach”)

d. The small intestine

e. The large intestine

For ruminants like cows, they don't chew the food in their mouth so much, just a little and then they swallow.

The half chewed corn mixes with saliva in the mouth and it is swallowed. From there it travels through the oesophagus and enters the first compartment of the stomach which is the Rumen.

The digestion of carbohydrates such as corn in ruminant animals occurs in the rumen through a process known as microbial fermentation.

Microorganisms that can be found in the rumen of a cow are: bacteria, protozoa and or fungi. These microorganisms break down the carbohydrates. The starch in which is the major molecule in the corn is broken down into fatty acids which are called volatile fatty acids. Examples include: Acetic acid, Butyric acid.

These acids are transferred to the liver of the cow through a portal vein in the wall of the rumen using the process of absorption where they serve as a source of energy for the cow.