Question

Which of the following statements about digestive physiology is correct?

(a) Glucose is enzymatically broken down by pancreatic amylase in the lumen of the small intestine.

(b) Relative to an herbivore such as the koala, a carnivore such as the coyote has a longer cecum that allows for the more efficient breakdown of ingested proteins.

(c) The rumen is the largest chamber of the alimentary canal of ruminants and is the primary site of microbial fermentation of ingested plant material.

(d) Both (a) and (b) are correct, and (c) is incorrect.

(e) Statements (a), (b), and (c) are all correct.

Answer 1

The rumen is the largest chamber in the ruminant digestive system and serves as the primary site for microbial fermentation of plant material. The small intestine absorbs the nutrients, whereas the large intestine is involved in waste elimination.

Step-by-step explanation:

The ruminant digestive system is adept at breaking down plant cell walls which contain cellulose. Ruminants such as cows, sheep, and goats have a multi-chambered stomach, with the largest chamber being the rumen. This chamber is crucial for the fermentation process, as it harbors a multitude of microbes that break down ingested plant material. The digestion process starts in the mouth where the animal chews and swallows food that enters the rumen for microbial fermentation. It may then be regurgitated as cud, re-chewed, and swallowed again. Following the rumen, food passes through the reticulum and omasum where further digestion and water absorption occur before finally entering the abomasum, also known as the "true" stomach, where digestive enzymes continue the digestive process. Hence, the statement that the rumen is the largest chamber of the alimentary canal of ruminants and is the primary site of microbial fermentation of ingested plant material is accurate.

Furthermore, the small intestine plays a vital role in nutrient absorption following the stomach chambers. The large intestine then ensures the proper elimination of waste. Understanding this complex digestive system is essential for comprehending how ruminants efficiently turn plant material into energy and nutrients necessary for their survival.