Which sequence correctly lists the stages of digestion in order?

Which sequence correctly lists the stages of digestion in order?

• A. Ingestion, Digestion, Absorption, Egestion
• B. Ingestion, Absorption, Digestion, Egestion
• C. Digestion, Ingestion, Absorption, Egestion
• D. Absorption, Ingestion, Digestion, Egestion

Answer: (A)

The main idea is the order in which food is processed: intake, breakdown, nutrient uptake, and waste elimination. Ingestion is taking food into the mouth. Digestion then breaks it down—mechanically by chewing and churning, and chemically with enzymes and acids—to produce smaller molecules. Absorption follows, mainly in the small intestine, where these nutrients pass into the bloodstream and/or lymph. Finally, egestion removes undigested material from the body as waste. This sequence makes sense because you can’t absorb nutrients that aren’t yet broken down, and digestion must occur before absorption and long before waste is expelled.

The main idea is the order in which food is processed: intake, breakdown, nutrient uptake, and waste elimination. Ingestion is taking food into the mouth. Digestion then breaks it down—mechanically by chewing and churning, and chemically with enzymes and acids—to produce smaller molecules. Absorption follows, mainly in the small intestine, where these nutrients pass into the bloodstream and/or lymph. Finally, egestion removes undigested material from the body as waste. This sequence makes sense because you can’t absorb nutrients that aren’t yet broken down, and digestion must occur before absorption and long before waste is expelled.