Question

In an empty stomach, the mucosa is thrown into folds called
A. Rugae
B. Villi
C. Alveoli
D. None of the above

Answer 1

Hint: The innermost layer of the stomach has a folded structure which is wrinkled in appearance and there is a specific term for that which you need to recall. The folds of the stomach mainly serve the purpose of digestion of food mechanically as well as movement of digested materials. Five layers constitute the stomach; mucosa, submucosa, muscularis, subserosa and serosa.

Complete answer:
> Rugae- When there is an empty stomach, the lining that is present is thrown up as folds. These are termed as the Rugae. They make the stomach more elastic and as a result more food can be accumulated and can move easily.

> Villi- They are the finger-like projections in the small intestine which mainly function to increase the surface area for maximum and efficient absorption of nutrients. It also adds digestive secretions.

> Alveoli- They are the sac-like structures that are located at the end of bronchioles. It is in the alveoli where the lungs and blood exchange the oxygen and carbon dioxide when a person breathes in and out.

Hence, the correct answer is option (A).

Additional information:
The five important layers of the stomach are
- Mucosa: It is a layer of cells that surrounds body organs and body aperture.
- Submucosa: It serves as a supportive structure for the mucosa. It has a high amount of blood vessels.
- Muscularis: It is the third layer composed of thick muscles. It aids the mixing of the food process with the digestive juices.
- Subserosa: It has tissues which support the serosa.
- Serosa: It lies towards the outermost side. It has lining that covers up the stomach.

Note: Mucosa is towards the innermost side. It is composed of various glands that secrete digestive juices (Pepsin and hydrochloric acid). Most cancers are known to have originated from here.