Question

List1	List2
A. Glucose	1. Duodenum, move as chylomicrons
B. Fructose	2. Small intestine facilitated diffusion
C. Glycerol, fatty acids	3. Large intestine, active absorption
D. Cholesterol, maltose	4. Glucose transporter

Select the correct match of the digested products in humans given in column I with their absorption site and mechanism in column II.

• A. A- 4, B- 2, C- 1, D- 3
• B. A- 2, B- 4, C- 1, D- 3
• C. A- 2, B- 4, C- 3, D- 1
• D. A- 2, B- 3, C- 4, D- 1

Answer 1

Answer: (A)

Absorption is the process by which the end products of digestion transported through the intestinal mucosa into the blood or lymph. The end products of digestion are absorbed in the jejunum and ileum regions of the small intestine. Small amounts of monosaccharide like glucose, amino acids, and some of the electrolytes like chloride ions are generally absorbed by simple diffusion.

Fructose and some amino acids are absorbed with the help of carrier ions like sodium. This mechanism is called facilitated transport. Various nutrients like amino acids, monosaccharide like glucose, electrolytes like $N{a}^{+}$ are reabsorbed into the blood by active transport.

Fatty acids and glycerol are insoluble in water, so they cannot be absorbed directly from the lumen of the intestine. With the help of bile salts and phospholipids, the fatty acids and glycerol are converted into small spherical water-soluble droplets, called as micelles.

Micelles are reformed into very small protein coated fat globules, called as chylomicrons which are transported into the lymph vessels (lacteals) in the villi. Chylomicrons contain triglycerides, cholesterol, and other lipids; they have proteins on their surface.

Thus, the correct answer is option A.