Quiz on Absorption in the Ileum

What is the primary function of the ileum in the small intestine?

• To produce digestive enzymes

• To absorb nutrients

• To secrete bile

• To store waste

Answer explanation

The primary function of the ileum, the final part of the small intestine, is to absorb nutrients from digested food into the bloodstream, making 'To absorb nutrients' the correct choice.

What are the tiny projections on the surface of the villus called?

• Crypts

• Microvilli

• Cilia

• Plicae

Answer explanation

The tiny projections on the surface of the villus are called microvilli. They increase the surface area for absorption in the intestines, distinguishing them from crypts, cilia, and plicae, which serve different functions.

How thick is the epithelial layer of the villus?

• Three cells thick

• One cell thick

• Two cells thick

• Four cells thick

Answer explanation

The epithelial layer of the villus is one cell thick, allowing for efficient absorption of nutrients. This thin layer facilitates the exchange of substances between the intestinal lumen and the bloodstream.

What is the role of goblet cells in the villus?

• To produce blood cells

• To transport fatty acids

• To secrete mucus

• To absorb nutrients

Answer explanation

Goblet cells in the villus secrete mucus, which lubricates the intestinal lining and aids in the movement of food. This function is crucial for digestion, making 'to secrete mucus' the correct answer.

What do blood capillaries in the villus help transport?

• Waste products

• Digestive products

• Oxygen

• Hormones

Answer explanation

Blood capillaries in the villus primarily transport digestive products, such as amino acids and sugars, absorbed from the intestine into the bloodstream, facilitating nutrient distribution throughout the body.

What does the lacteal in the villus carry?

• Vitamins

• Droplets of fatty acids and glycerol

• Amino acids

• Glucose

Answer explanation

The lacteals in the villi of the small intestine specifically transport droplets of fatty acids and glycerol, which are products of fat digestion, into the lymphatic system, distinguishing them from other nutrients like amino acids and glucose.

What is the purpose of the intestinal glands in the ileum?

• To absorb nutrients

• To secrete intestinal juices

• To store bile

• To filter blood

What adaptation do microvilli provide to the villus?

• Increased blood flow

• Increased surface area

• Increased mucus production

• Decreased absorption time

Answer explanation

Microvilli increase the surface area of the villus, allowing for more efficient absorption of nutrients in the intestines. This adaptation is crucial for maximizing nutrient uptake.

Which of the following is NOT a component of the villus?

• Pancreatic cells

• Epithelial cells

• Goblet cells

• Lacteal

Answer explanation

Pancreatic cells are not found in the villus; they are part of the pancreas and involved in digestion. The villus contains epithelial cells, goblet cells, and a lacteal, which are essential for nutrient absorption.

What is the main benefit of the villus being one cell thick?

• It helps in digestion

• It increases the surface area

• It prevents bacteria from entering

• It allows for faster nutrient absorption

Answer explanation

The villus being one cell thick allows for faster nutrient absorption because it minimizes the distance nutrients must travel to enter the bloodstream, enhancing efficiency in nutrient uptake.