Gastrointestinal Digestive System Anatomy

Question 1

Which organ is primarily responsible for nutrient absorption?

Accepted Answer

Small intestine

Answer

The small intestine is the primary site for the absorption of nutrients from digested food. Its inner surface is lined with villi and microvilli, which greatly increase the surface area available for efficient absorption of carbohydrates, proteins, fats, vitamins, and minerals into the bloodstream. While digestion begins elsewhere, absorption is maximized here.

Question 2

What is the primary function of the large intestine?

Accepted Answer

Absorption of water and electrolytes

Answer

The large intestine's primary function is to absorb water and electrolytes from the remaining indigestible food matter. This process helps to solidify the waste material, forming feces, before it is eliminated from the body. It also houses beneficial bacteria that produce certain vitamins.

Question 3

Which enzyme is responsible for breaking down proteins in the stomach?

Accepted Answer

Pepsin

Answer

Pepsin is the primary enzyme responsible for breaking down proteins in the stomach. It is secreted in an inactive form called pepsinogen, which is then activated by hydrochloric acid in the stomach. Once active, pepsin cleaves proteins into smaller polypeptides, initiating their digestion.

Question 4

Which structure prevents food from entering the trachea during swallowing?

Accepted Answer

Epiglottis

Answer

The epiglottis is a leaf-shaped flap of cartilage located at the base of the tongue. During swallowing, it folds down to cover the opening of the larynx and trachea. This crucial action prevents food and liquids from entering the respiratory tract, directing them instead into the esophagus.

Question 5

What is the primary function of bile in digestion?

Accepted Answer

Emulsifies fats

Answer

Bile, produced by the liver and stored in the gallbladder, contains bile salts that act as emulsifiers. Emulsification is the process of breaking down large fat globules into smaller droplets. This increases the surface area of the fats, making them more accessible for digestion by lipase enzymes in the small intestine.

(GI) Gastrointestinal Practice Test

(GI) Gastrointestinal Practice Test

Gastrointestinal Digestive System Anatomy