Igcse Model Questions Vol1 2019 Biology Question 3

Practice essay / theory question 3 from the 2019 Igcse Model Questions Vol1 Biology examination. This question covers Nutrition, Digestive system, Enzymes, Absorption .

Igcse Model Questions Vol1 2019 Biology Essay / Theory
Topics: Nutrition Digestive system Enzymes Absorption
Question 3 IGCSE_MODEL_QUESTIONS_VOL1 • 2019 • BIOLOGY • essay

The diagram shows the human digestive system with the following labelled parts: A – Mouth, B – Esophagus, C – Stomach, D – Liver, E – Pancreas, F – Small intestine, G – Large intestine.

Question Parts

( a )
Identify three organs shown in the diagram that are directly involved in chemical digestion. For each organ, name the principal enzyme it secretes and briefly describe the role of that enzyme in digestion.
( b )
Explain how the structure of the small intestine (part F) maximises the absorption of nutrients.
( c )
A person lacks the enzyme lactase. Explain the likely symptoms they would experience after drinking milk and the physiological reason for those symptoms.
( d )
The inner surface of the small intestine is covered with approximately 10⁹ villi. Each villus contributes about 0.02 mm² to the absorptive area. (i) Estimate the total additional surface area provided by the villi in square metres. (ii) Discuss why such a large surface area is important for digestion.

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About This Question

This is Igcse Model Questions Vol1 2019 Biology Question 3. It is one of the essay questions from the 2019 Igcse Model Questions Vol1 Biology examination.

The question covers Nutrition, Digestive system, Enzymes, Absorption .

View More Igcse Model Questions Vol1 2019 Biology Questions More Igcse Model Questions Vol1 Practice Questions Back to Questions

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