Chemical digestion — Paper 1 · IGCSE Biology (9-1) 0970

10 The apparatus shown is used for an experiment on starch digestion. Which test-tube contains the most sugar after 20 minutes? A B C D starch starch solution starch solution and salivary solution and salivary amylase amylase water-bath at 15 °C water-bath at 37 °C

1 marks

Answer: D

This question in 0970/12 Oct/Nov 2018

14 Which row shows an enzyme with the correct site of production and products? enzyme product(s) enzyme produced by of digestion A amylase salivary glands amino acids B amylase stomach sugar C protease salivary glands sugar D protease stomach amino acids

1 marks

Answer: D

This question in 0970/12 Oct/Nov 2018

15 The diagram shows a human tooth with an area of decay. area of decay What is likely to have caused the decay? A acids released by bacteria B digestion of the tooth by bacteria C excess of fat in the food D lack of fibre in the food

1 marks

Answer: A

This question in 0970/11 May/June 2019

14 The diagram shows an experiment kept at room temperature. tubing containing starch, protease, test-tube protein and simple sugars distilled water membrane permeable to small molecules only What is present in the water surrounding the membrane after 45 minutes? A amino acids and simple sugars B protein and amino acids C protein and simple sugars D starch and simple sugars

1 marks

Answer: A

This question in 0970/12 Oct/Nov 2019

26 Which organ secretes amylase? A colon B liver C pancreas D stomach

1 marks

Answer: C

This question in 0970/12 Oct/Nov 2019

12 The activity of amylase is measured in four parts of the alimentary canal. Which two parts have the most amylase activity? A colon and duodenum B colon and stomach C mouth and duodenum D stomach and mouth

1 marks

Answer: C

This question in 0970/11 May/June 2020

12 The graph shows the effect of pH on the activity of an enzyme. enzyme activity 1 3 5 7 9 11 pH In which part of the alimentary canal would this enzyme be most active? A large intestine B mouth C small intestine D stomach

1 marks

Answer: D

This question in 0970/12 May/June 2020

15 The diagram shows the apparatus used in an experiment to demonstrate two processes that take place in the body. test-tube pure water dialysis tubing ends dialysis tubing which tightly is partially permeable sealed mixture of saliva and starch solution After one hour, the water outside the dialysis tubing contained reducing sugars. Which two processes are represented by this experiment? A absorption and digestion B absorption and egestion C digestion and egestion D digestion and ingestion

1 marks

Answer: A

This question in 0970/12 Oct/Nov 2020

10 Starch is digested by amylase in the mouth, but it is not digested in the stomach. What is the reason for this? A All starch digestion is completed in the mouth. B The pH in the stomach is not suitable for the amylase to work. C The starch does not stay in the stomach long enough to be digested. D The temperature in the stomach is not suitable for the amylase to work.

1 marks

Answer: B

This question in 0970/11 May/June 2021

15 What are the products when proteins are broken down? A amino acids B fatty acids C glycerol D simple sugars

1 marks

Answer: A

This question in 0970/11 May/June 2021

11 Four test-tubes were set up as shown in the diagram. In which test-tube is the starch digested most quickly? A B C D water-bath water-bath at 15 °C at 35 °C starch solution starch solution and amylase and amylase starch solution starch solution and boiled amylase and boiled amylase

1 marks

Answer: C

This question in 0970/12 Oct/Nov 2021

15 The diagram shows a large food molecule changing into smaller molecules. process X What is process X? A absorption B chewing C digestion D secretion

1 marks

Answer: C

This question in 0970/12 Oct/Nov 2021

15 Which statement is correct? A Amylase breaks down glucose to starch. B Amylase is secreted into the mouth and small intestine. C Lipase breaks down glycerol to fatty acids. D Protease is secreted into the oesophagus and stomach.

1 marks

Answer: B

This question in 0970/12 Oct/Nov 2022

16 Solid food enters the mouth at P and enters the oesophagus at Q. P Q How does the food at Q differ from the food at P? A It contains less fibre. B It contains less water. C It contains less protein. D It contains less starch.

1 marks

Answer: D

This question in 0970/11 May/June 2023

7 What is a role of water in digestion? A It is an enzyme. B It is a solvent. C It is soluble. D It is a mineral.

1 marks

Answer: B

This question in 0970/12 May/June 2023

14 Some medicines are made into tablets which are coated in a starch-like substance. The coating protects the medicine from the effects of gastric juice. Which enzyme digests the coating and what is produced by this action? enzyme products A amylase fatty acids and glycerol B amylase simple reducing sugars C lipase fatty acids and glycerol D lipase simple reducing sugars

1 marks

Answer: B

This question in 0970/12 Oct/Nov 2023

17 What is the function of the gall bladder? A production of bile B production of gastric juice C storage of bile D storage of gastric juice

1 marks

Answer: C

This question in 0970/11 May/June 2024

19 A person ate food X. Chemical digestion of food X occurred in the mouth and small intestine but not in the stomach. What was in food X? A fat B ions C protein D starch

1 marks

Answer: D

This question in 0970/11 May/June 2024

19 Where does protease act? A B C D

1 marks

Answer: C

This question in 0970/12 May/June 2024

40 The diagram shows a label found on a container of biological washing powder. Biological washing powder • works at low temperatures • contains protease • contains lipase • keep out of reach of children Which stains does the washing powder remove? food stain food stain food stain food stain containing containing containing containing oil carbohydrates protein fat A ✓ ✓ ✗ ✗ key B ✓ ✗ ✗ ✓ ✓= yes C ✗ ✓ ✓ ✓ ✗= no D ✗ ✗ ✓ ✗

1 marks

Answer: C

This question in 0970/12 May/June 2024

18 The diagram shows the four types of teeth in a human jaw. top view side view 3 3 1 4 2 1 4 2 Which row correctly identifies all four types of teeth? 1 2 3 4 A canine incisor molar premolar B canine molar incisor premolar C premolar incisor molar canine D premolar molar incisor canine

1 marks

Answer: B

This question in 0970/12 Oct/Nov 2024

19 What are the products of protein digestion in the stomach? A amino acids B fatty acids C glycerol D proteases

1 marks

Answer: A

This question in 0970/12 Oct/Nov 2024

17 Which row shows an enzyme with the correct site of production and products of digestion? site of products enzyme production of digestion A amylase salivary glands amino acids B amylase stomach simple reducing sugars C protease salivary glands simple reducing sugars D protease stomach amino acids

1 marks

Answer: D

This question in 0970/11 May/June 2025

14 The diagram shows part of the human digestive system. Where does amylase act on food? D A C B

1 marks

Answer: C

This question in 0970/12 May/June 2025

11 The graphs show the effect of pH on the activity of four different digestive enzymes. Which enzyme is most active in the stomach? A B 100 100 percentage percentage activity 50 activity 50 0 0 0 2 4 6 8 10 12 0 2 4 6 8 10 12 pH pH C D 100 100 percentage percentage activity 50 activity 50 0 0 0 2 4 6 8 10 12 0 2 4 6 8 10 12 pH pH

1 marks

Answer: C

This question in 0970/12 Oct/Nov 2025

12 In which organ does physical digestion and chemical digestion occur? A gall bladder B liver C pancreas D stomach

1 marks

Answer: D

This question in 0970/12 Oct/Nov 2025