Question

Pick out an animal that has a four-chambered stomach.
A. Elephant
B. Dolphin
C. Human
D. Kangaroo

Answer 1

Hint: Ruminants are known to have a stomach with four chambers, Ruminants are herbivorous animals and they obtain their nutrition from plants with the help of microbes.

Complete Answer:
The ruminants have a four-chambered stomach, the four chambers are Rumen, Reticulum, omasum, abomasum, The microbial actions take place in rumen and reticulum together known as reticulorumen. Microbial action is important to break-down complex foods like cellulose, etc. The degraded food is then passed to the omasum and the abomasum.

- Option(A): Elephant is considered a ruminant due to its complex digestive system, Therefore this is the Correct option.
- Option(B): Dolphin is not a ruminant, Therefore this is an Incorrect option.
- Option(C): Humans are carnivores and are not ruminant, Therefore this is an Incorrect option.
- Option(D): Kangaroo is also non-ruminants, Therefore this is an Incorrect option.

Hence the correct answer is option A.

Additional Information:
-Ruminants have this complex stomach because they need to ferment the food to obtain nutrition, They chew their food then regurgitate, and then chew the food again, this is also known as a rumination of food and the regurgitated food is known as cud.
-Volatile fatty acids and ammonia in ruminants are absorbed by omasum.
-Abomasum is known as the true stomach of ruminants.
-The saliva of ruminant animals acts as a buffer for the pH of the rumen.

Note: - The microbes in the stomach of ruminants function the best at pH around 6-6.5, warm and moist environment, and anaerobic conditions.
- Cellulose and Hemicellulose in ruminants are broken down into acetic acid, propionic acid, and butyric acid which are also known as volatile fatty acids by microbes like bacteria, protozoans, fungus, etc