Which term describes the physical breakdown of food through chewing?

Which term describes the physical breakdown of food through chewing?

• A. Chemical digestion
• B. Absorption
• C. Enzymatic digestion
• D. Mechanical digestion

Answer: (D)

Mechanical digestion is the physical breakdown of food into smaller pieces through chewing, grinding, and mixing. In the mouth, teeth and jaw movements crush and tear food, while the tongue helps form a cohesive bolus. This process increases the surface area of the food so enzymes can work more efficiently later, but it does not change the chemical composition of the molecules. This is different from chemical digestion, which uses enzymes to break chemical bonds, and from absorption, which is the uptake of nutrients into the bloodstream. So chewing represents mechanical digestion because its role is to physically reduce particle size rather than chemically alter the food.

Mechanical digestion is the physical breakdown of food into smaller pieces through chewing, grinding, and mixing. In the mouth, teeth and jaw movements crush and tear food, while the tongue helps form a cohesive bolus. This process increases the surface area of the food so enzymes can work more efficiently later, but it does not change the chemical composition of the molecules. This is different from chemical digestion, which uses enzymes to break chemical bonds, and from absorption, which is the uptake of nutrients into the bloodstream. So chewing represents mechanical digestion because its role is to physically reduce particle size rather than chemically alter the food.