Chapter 6 Practice Paper: Human Digestive System — question paper

Section A: Multiple-choice questions[10 marks]

Answer all questions. For each question, write the letter (A, B, C or D) of the correct answer in the brackets provided.

1. 1

   During digestion, large food molecules are broken down into

   1. Asmaller molecules that can be absorbed.
   2. Boxygen.
   3. Cfibre that cannot be digested.
   4. Dnew elements.
   ( )
2. 2

   A bite of rice passes from the mouth into a muscular tube before it reaches the stomach. That tube is the

   1. Alarge intestine.
   2. Brectum.
   3. Cgullet.
   4. Dxylem.
   ( )
3. 3

   Digested food enters the blood mainly in the

   1. Astomach.
   2. Bsmall intestine.
   3. Cmouth.
   4. Danus.
   ( )
4. 4

   Which food type is digested by proteases?

   1. Afats.
   2. Bstarch only.
   3. Cwater.
   4. Dproteins.
   ( )
5. 5

   Which food type is digested by lipases?

   1. Afats.
   2. Bproteins.
   3. Cminerals.
   4. Dwater.
   ( )
6. 6

   Water is taken back into the blood from undigested remains mainly in the

   1. Amouth.
   2. Bgullet.
   3. Clarge intestine.
   4. Dstomach only.
   ( )
7. 7

   Egestion removes

   1. Acarbon dioxide from the lungs.
   2. Burine.
   3. Cheat from the skin.
   4. Dundigested food from the anus.
   ( )
8. 8

   Chewing food speeds enzyme action mainly because it

   1. Aturns fats into proteins.
   2. Bincreases the surface area of the food.
   3. Cabsorbs the food in the mouth.
   4. Dreplaces the gullet.
   ( )
9. 9

   The enzyme class that digests starch is

   1. Acarbohydrases.
   2. Bproteases.
   3. Clipases.
   4. Dplatelets.
   ( )
10. 10

    Which order matches the path of food?

    1. Astomach → mouth → small intestine
    2. Banus → stomach → mouth
    3. Cmouth → gullet → stomach → small intestine
    4. Dsmall intestine → mouth → stomach
    ( )

Section B: Structured questions[20 marks]

Answer all questions in the spaces provided. Show your working for calculations.

1. 1

   A student eats a piece of bread. The bread contains starch.

   1. (a)

      Name the enzyme class that digests starch.

      [1]
   2. (b)

      State where digestion of the starch starts.

      [1]
   3. (c)

      State where digestion of the starch is completed.

      [1]
   4. (d)

      State where the products are absorbed, and what carries them away.

      [2]
2. 2

   A meal contains rice, chicken and cooking oil.

   1. (a)

      Name the enzyme class for the rice, the chicken and the oil.

      [3]
   2. (b)

      Describe two things the stomach does to the food.

      [2]
3. 3

   Digestion, absorption, egestion and excretion are different processes.

   1. (a)

      State how digestion differs from absorption.

      [2]
   2. (b)

      Faeces leave the anus, and carbon dioxide leaves the lungs. State which process is egestion, which is excretion, and why they are not the same process.

      [2]
   3. (c)

      State what the large intestine absorbs from the undigested remains.

      [1]
4. 4

   A person eats very little fibre and drinks very little water.

   1. (a)

      Explain why food molecules must be small before they can enter the blood.

      [2]
   2. (b)

      Predict one effect of the low fibre and low water on the large intestine.

      [2]
   3. (c)

      A clinic poster links daily walks and meals that are not very sugary with a lower chance of type 2 diabetes. State one habit the poster is recommending.

      [1]