Which components are involved in mechanical digestion?

Which components are involved in mechanical digestion?

• A. Teeth, tongue, peristalsis
• B. Enzymes, acids, bile
• C. Villi, microvilli, lacteals
• D. Liver, pancreas, gallbladder

Answer: (A)

Mechanical digestion is the physical breakdown of food into smaller pieces to increase surface area for enzymes to work. The teeth do the actual grinding and shredding, while the tongue helps shape the food into a cohesive bolus and positions it for efficient chewing. Peristalsis then physically moves and mixes this material along the digestive tract, continuing the breakdown through successive muscular contractions. Together, teeth, tongue, and peristalsis accomplish the targeted physical processing before chemical digestion takes over. The other options involve processes and structures not primarily responsible for mechanical digestion: enzymes, acids, and bile drive chemical digestion; villi, microvilli, and lacteals relate to absorption; and the liver, pancreas, and gallbladder are organs that secrete digestive fluids rather than directly performing mechanical breakdown.

Mechanical digestion is the physical breakdown of food into smaller pieces to increase surface area for enzymes to work. The teeth do the actual grinding and shredding, while the tongue helps shape the food into a cohesive bolus and positions it for efficient chewing. Peristalsis then physically moves and mixes this material along the digestive tract, continuing the breakdown through successive muscular contractions. Together, teeth, tongue, and peristalsis accomplish the targeted physical processing before chemical digestion takes over.

The other options involve processes and structures not primarily responsible for mechanical digestion: enzymes, acids, and bile drive chemical digestion; villi, microvilli, and lacteals relate to absorption; and the liver, pancreas, and gallbladder are organs that secrete digestive fluids rather than directly performing mechanical breakdown.