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Primary 4 Science Practice Paper 1
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Questions
TuitionGoWhere Practice Paper - Science Primary 4
TuitionGoWhere Practice Paper (AI)
Subject: Science
Level: Primary 4
Paper: Practice Paper 1 (Version 1)
Duration: 1 hour 30 minutes
Total Marks: 60
Name: ________________________
Class: Primary 4 ______
Date: _______________
Instructions to Candidates
- Do not open this booklet until you are told to do so.
- Follow all instructions carefully.
- Answer all questions.
- Write your answers in this booklet.
- The number of marks is given in brackets [ ] at the end of each question or part question.
- The total marks for this paper is 60.
Section A: Multiple-Choice Questions (20 marks)
For each question from 1 to 10, four options are given. Choose the correct answer and write its number (1, 2, 3 or 4) in the brackets provided.
Question 1 [2 marks]
Which of the following groups contains only living things?
(1) Mushroom, moss, rock
(2) Bacteria, yeast, mould
(3) Cloud, river, soil
(4) Robot, car, computer
Answer: (_____)
Question 2 [2 marks]
Study the classification chart below.
<image_placeholder> id: Q2-fig1 type: diagram linked_question: Q2 description: Classification chart showing two groups - Group X and Group Y. Group X contains: Rose plant, Hibiscus plant, Balsam plant. Group Y contains: Mushroom, Yeast, Mould. Arrows point from each item to its group. labels: Group X, Group Y, Rose plant, Hibiscus plant, Balsam plant, Mushroom, Yeast, Mould values: None must_show: Clear separation into two groups with three examples each, group labels visible </image_placeholder>
Which of the following headings best represent Group X and Group Y?
| Group X | Group Y | |
|---|---|---|
| (1) | Flowering plants | Non-flowering plants |
| (2) | Plants | Fungi |
| (3) | Living things | Non-living things |
| (4) | Reproduce by seeds | Reproduce by spores |
Answer: (_____)
Question 3 [2 marks]
Which of the following statements about bacteria is correct?
(1) All bacteria are harmful to humans.
(2) Bacteria can only be seen with a microscope.
(3) Bacteria are non-living things.
(4) Bacteria reproduce by laying eggs.
Answer: (_____)
Question 4 [2 marks]
Four pupils made the following statements about fungi:
- Ali: "All fungi are microorganisms."
- Bala: "Fungi make their own food like plants."
- Cindy: "Yeast and mould are examples of fungi."
- Devi: "Fungi reproduce by seeds."
Who made the correct statement(s)?
(1) Ali only
(2) Cindy only
(3) Ali and Cindy
(4) Bala and Devi
Answer: (_____)
Question 5 [2 marks]
Study the flowchart below.
<image_placeholder> id: Q5-fig1 type: diagram linked_question: Q5 description: Flowchart for classifying living things. Start: "Is it a living thing?" Yes -> "Does it make its own food?" Yes -> "Flowering plant?" Yes -> A, No -> B. No (from make own food) -> "Does it have hair/fur?" Yes -> C, No -> "Does it have feathers?" Yes -> D, No -> "Does it have scales?" Yes -> E, No -> F. labels: Start, Living thing?, Make own food?, Flowering plant?, A, B, Hair/fur?, C, Feathers?, D, Scales?, E, F values: None must_show: Clear decision diamond shapes, yes/no branches, endpoints A-F </image_placeholder>
Which of the following could represent organism A?
(1) Mango tree
(2) Fern
(3) Mushroom
(4) Moss
Answer: (_____)
Question 6 [2 marks]
Which of the following is a characteristic of all living things?
(1) They can move from place to place.
(2) They need air, food and water.
(3) They reproduce by laying eggs.
(4) They have legs to walk.
Answer: (_____)
Question 7 [2 marks]
The diagram below shows a plant.
<image_placeholder> id: Q7-fig1 type: diagram linked_question: Q7 description: Diagram of a flowering plant with roots, stem, leaves, flowers, and fruits clearly labelled. The plant has visible flowers and a fruit developing from a flower. labels: Roots, Stem, Leaves, Flowers, Fruit values: None must_show: Complete flowering plant with all parts labelled, flower and fruit clearly visible </image_placeholder>
Based on the diagram, which of the following statements is correct?
(1) The plant reproduces by spores.
(2) The plant is a non-flowering plant.
(3) The plant makes its own food.
(4) The plant cannot respond to changes.
Answer: (_____)
Question 8 [2 marks]
Which of the following groups of animals are correctly matched to their outer coverings?
| Animal | Outer Covering | |
|---|---|---|
| (1) | Snake | Feathers |
| (2) | Frog | Scales |
| (3) | Penguin | Feathers |
| (4) | Earthworm | Hair |
Answer: (_____)
Question 9 [2 marks]
Study the table below.
| Organism | Makes own food | Reproduces by spores | Has roots, stem, leaves |
|---|---|---|---|
| P | Yes | No | Yes |
| Q | No | Yes | No |
| R | Yes | Yes | No |
Which of the following correctly identifies organisms P, Q and R?
| P | Q | R | |
|---|---|---|---|
| (1) | Rose plant | Mushroom | Fern |
| (2) | Fern | Mushroom | Rose plant |
| (3) | Mushroom | Fern | Rose plant |
| (4) | Rose plant | Fern | Mushroom |
Answer: (_____)
Question 10 [2 marks]
Which of the following statements about microorganisms is true?
(1) All microorganisms cause diseases.
(2) Microorganisms can only live in water.
(3) Some microorganisms are useful to humans.
(4) Microorganisms are non-living things.
Answer: (_____)
Section B: Structured Questions (20 marks)
Answer all questions in the spaces provided.
Question 11 [4 marks]
The diagram below shows four organisms: W, X, Y and Z.
<image_placeholder> id: Q11-fig1 type: diagram linked_question: Q11 description: Four separate organism diagrams. W: A mushroom with visible cap and stem. X: A balsam plant with flowers. Y: A bird (sparrow) with feathers, beak, wings. Z: A fish (guppy) with scales, fins, gills visible. labels: W, X, Y, Z values: None must_show: Four distinct organisms clearly identifiable as mushroom, flowering plant, bird, fish </image_placeholder>
(a) Which organism(s) is/are a plant? ________________________ [1]
(b) Which organism(s) reproduce(s) by spores? ________________________ [1]
(c) State one similarity between organisms Y and Z. ________________________ [1]
(d) State one difference between organisms W and X. ________________________ [1]
Question 12 [4 marks]
Classify the following living things into the correct groups in the table below.
Living things:
Moss, Hibiscus, Bacteria, Yeast, Fern, Mould, Bird's nest fern, Rose plant
| Flowering Plants | Non-flowering Plants | Fungi | Bacteria |
|---|---|---|---|
[4 marks - 0.5 marks each correct placement]
Question 13 [4 marks]
The flowchart below shows how some animals are classified.
<image_placeholder> id: Q13-fig1 type: diagram linked_question: Q13 description: Flowchart for animal classification. Start: "Animal" -> "Does it have 6 legs?" Yes -> "Does it have wings?" Yes -> A, No -> B. No (from 6 legs) -> "Does it have hair/fur?" Yes -> C, No -> "Does it have feathers?" Yes -> D, No -> "Does it live in water and have gills?" Yes -> E, No -> F. labels: Animal, 6 legs?, Wings?, A, B, Hair/fur?, C, Feathers?, D, Water and gills?, E, F values: None must_show: Clear decision points with yes/no branches, endpoints A-F </image_placeholder>
(a) Which group (A, B, C, D, E or F) would a butterfly belong to? ______ [1]
(b) Which group would a grasshopper belong to? ______ [1]
(c) State one characteristic of animals in group C. ________________________ [1]
(d) State one characteristic of animals in group E. ________________________ [1]
Question 14 [4 marks]
Peter found an unknown organism in his garden. He observed the following:
- It is green in colour.
- It has roots, a stem and leaves.
- It does not have flowers.
- It reproduces by spores.
(a) Based on the observations, which group of plants does this organism belong to? ________________________ [1]
(b) Name one example of a plant from this group. ________________________ [1]
(c) State one difference between this group of plants and flowering plants. ________________________ [1]
(d) Explain why this organism is classified as a plant and not a fungus. ________________________ [1]
Question 15 [4 marks]
The table below shows the characteristics of four organisms P, Q, R and S.
| Organism | Makes own food | Reproduces by spores | Has chlorophyll | Microscopic |
|---|---|---|---|---|
| P | Yes | No | Yes | No |
| Q | No | Yes | No | Yes |
| R | No | Yes | No | No |
| S | Yes | Yes | Yes | No |
(a) Which organism(s) is/are plant(s)? ________________________ [1]
(b) Which organism is most likely a bacterium? ________________________ [1]
(c) Which organism is most likely a fungus (mould or yeast)? ________________________ [1]
(d) Which organism is most likely a fern? ________________________ [1]
Section C: Open-Ended Questions (20 marks)
Answer all questions in the spaces provided.
Question 16 [5 marks]
The diagram below shows the life cycle of a butterfly.
<image_placeholder> id: Q16-fig1 type: diagram linked_question: Q16 description: Life cycle diagram of a butterfly showing four stages in a circle: Egg -> Caterpillar (Larva) -> Pupa (Chrysalis) -> Adult Butterfly -> back to Egg. Arrows show direction. Each stage labelled. labels: Egg, Caterpillar (Larva), Pupa (Chrysalis), Adult Butterfly values: None must_show: Four distinct stages in cyclic arrangement, clear arrows, all stages labelled </image_placeholder>
(a) Name the stage marked X in the diagram. ________________________ [1]
(b) At which stage does the butterfly cause the most damage to plants? Explain your answer. ________________________ [2]
(c) State one difference between the young and the adult butterfly. ________________________ [1]
(d) The butterfly undergoes complete metamorphosis. Name another insect that undergoes complete metamorphosis. ________________________ [1]
Question 17 [5 marks]
Study the classification table below.
| Group | Characteristics | Examples |
|---|---|---|
| A | Make own food, have roots, stem, leaves, reproduce by seeds | Rambutan tree, Sunflower |
| B | Make own food, have roots, stem, leaves, reproduce by spores | Bird's nest fern, Moss |
| C | Cannot make own food, reproduce by spores, microscopic | Bacteria |
| D | Cannot make own food, reproduce by spores, not microscopic | Mushroom, Mould |
(a) What are the headings for Group A and Group B?
Group A: ________________________
Group B: ________________________ [2]
(b) State one similarity between Group B and Group D. ________________________ [1]
(c) State one difference between Group C and Group D. ________________________ [1]
(d) Yeast is a fungus. In which group (A, B, C or D) should yeast be placed? ______ [1]
Question 18 [5 marks]
Ahmad conducted an investigation to find out if yeast needs water to grow. He set up two set-ups as shown below.
<image_placeholder> id: Q18-fig1 type: experimental_setup linked_question: Q18 description: Two test tubes side by side. Set-up A: Test tube with 5g yeast + 5g sugar + 20ml water. Balloon attached to top. Set-up B: Test tube with 5g yeast + 5g sugar + 0ml water. Balloon attached to top. Both placed in warm water bath at 35°C. labels: Set-up A, Set-up B, Yeast, Sugar, Water, Balloon, Warm water bath, 35°C values: 5g yeast, 5g sugar, 20ml water (A), 0ml water (B), 35°C must_show: Two test tubes with clear labels showing contents, balloons on top, water bath with temperature </image_placeholder>
(a) What is the aim of Ahmad's investigation? ________________________ [1]
(b) Which set-up is the control set-up? Explain your answer. ________________________ [2]
(c) After 30 minutes, the balloon in Set-up A became inflated but the balloon in Set-up B remained flat. What does this tell you about the conditions needed for yeast to grow? ________________________ [1]
(d) State one other condition that yeast needs to grow, besides the one tested in this investigation. ________________________ [1]
Question 19 [5 marks]
The diagram below shows a plant cell and an animal cell.
<image_placeholder> id: Q19-fig1 type: diagram linked_question: Q19 description: Two cells side by side. Left: Plant cell - rectangular, cell wall, cell membrane, cytoplasm, nucleus, chloroplasts, large vacuole. Right: Animal cell - irregular/round, cell membrane, cytoplasm, nucleus, small vacuoles. Both labelled. labels: Plant cell, Animal cell, Cell wall, Cell membrane, Cytoplasm, Nucleus, Chloroplast, Vacuole values: None must_show: Clear structural differences: cell wall present in plant only, chloroplasts in plant only, large vacuole in plant, small vacuoles in animal, shape difference </image_placeholder>
(a) Identify two structures found in the plant cell but not in the animal cell.
-
- ________________________ [2]
(b) State the function of the chloroplast. ________________________ [1]
(c) Why do animal cells not have chloroplasts? ________________________ [1]
(d) Both cells have a nucleus. State the function of the nucleus. ________________________ [1]
Question 20 [5 marks]
Read the passage below and answer the questions that follow.
The Amazing World of Microorganisms
Microorganisms are living things that are too small to be seen with the naked eye. They can only be seen under a microscope. There are three main groups of microorganisms: bacteria, fungi and viruses.
Bacteria are single-celled organisms found almost everywhere - in soil, water, air, and even inside our bodies. Some bacteria are harmful and cause diseases like food poisoning and tooth decay. However, many bacteria are useful. For example, bacteria in our intestines help us digest food, and bacteria are used to make yoghurt and cheese.
Fungi include yeast, mould and mushrooms. Yeast is used to make bread rise and to brew beer. Mould grows on damp food and can cause food spoilage. Some fungi are used to produce antibiotics like penicillin.
Viruses are the smallest microorganisms. They can only reproduce inside living cells. Viruses cause diseases such as the common cold, influenza and COVID-19.
(a) State one way in which bacteria are useful to humans. ________________________ [1]
(b) State one way in which fungi can be harmful. ________________________ [1]
(c) Why are viruses considered different from bacteria and fungi? ________________________ [1]
(d) Complete the table below with examples of microorganisms.
| Type of Microorganism | Example | Use / Harm |
|---|---|---|
| Bacteria | _______________ | Make yoghurt |
| Fungi (Yeast) | _______________ | Make bread rise |
| Viruses | _______________ | Cause COVID-19 |
[2 marks - 0.5 marks each correct entry]
End of Paper
Total Marks: 60
Answers
TuitionGoWhere Practice Paper - Science Primary 4 (Answer Key)
Subject: Science
Level: Primary 4
Paper: Practice Paper 1 (Version 1)
Total Marks: 60
Section A: Multiple-Choice Questions (20 marks)
Question 1 [2 marks]
Answer: (2)
Explanation: Bacteria, yeast and mould are all microorganisms (living things). Mushroom is a fungus (living) but rock is non-living. Cloud, river, soil are non-living. Robot, car, computer are man-made non-living things.
Question 2 [2 marks]
Answer: (2)
Explanation: Group X contains flowering plants (rose, hibiscus, balsam) which are plants. Group Y contains mushroom, yeast, mould which are fungi. Option (1) is incorrect because Group Y are not non-flowering plants (they are fungi). Option (3) is incorrect because both groups are living things. Option (4) is incorrect because flowering plants reproduce by seeds but fungi reproduce by spores.
Question 3 [2 marks]
Answer: (2)
Explanation: Bacteria are microscopic organisms and can only be seen with a microscope. Not all bacteria are harmful (many are useful). Bacteria are living things (they reproduce, need food, respire). Bacteria reproduce by binary fission (splitting), not by laying eggs.
Question 4 [2 marks]
Answer: (2)
Explanation: Cindy is correct - yeast and mould are examples of fungi. Ali is incorrect because not all fungi are microorganisms (mushrooms are macroscopic fungi). Bala is incorrect because fungi cannot make their own food (they are decomposers). Devi is incorrect because fungi reproduce by spores, not seeds.
Question 5 [2 marks]
Answer: (1)
Explanation: Following the flowchart: Living thing → Makes own food (Yes) → Flowering plant (Yes) → A. A mango tree is a flowering plant that makes its own food. Ferns make their own food but are non-flowering (reproduce by spores). Mushrooms are fungi (don't make own food). Mosses are non-flowering plants.
Question 6 [2 marks]
Answer: (2)
Explanation: All living things need air, food and water to survive. Not all living things can move from place to place (plants are living but fixed). Not all reproduce by laying eggs (mammals give birth, plants produce seeds/spores). Not all have legs (snakes, fish, plants).
Question 7 [2 marks]
Answer: (3)
Explanation: The diagram shows a flowering plant with leaves. Plants make their own food through photosynthesis in their leaves. It reproduces by seeds (from flowers/fruit), not spores. It is a flowering plant. Plants can respond to changes (e.g., grow towards light).
Question 8 [2 marks]
Answer: (3)
Explanation: Penguins are birds and have feathers. Snakes have scales, not feathers. Frogs have moist skin, not scales. Earthworms have segmented bodies with setae, not hair.
Question 9 [2 marks]
Answer: (1)
Explanation: P: Makes own food (Yes), reproduces by spores (No), has roots/stem/leaves (Yes) → Rose plant (flowering plant). Q: Makes own food (No), reproduces by spores (Yes), no roots/stem/leaves → Mushroom (fungus). R: Makes own food (Yes), reproduces by spores (Yes), no roots/stem/leaves → Fern (non-flowering plant).
Question 10 [2 marks]
Answer: (3)
Explanation: Some microorganisms are useful (e.g., bacteria in yoghurt, yeast in bread, penicillin from fungi). Not all cause diseases. Microorganisms live in many places, not only water. Microorganisms are living things.
Section B: Structured Questions (20 marks)
Question 11 [4 marks]
(a) X [1]
Explanation: X is the balsam plant which has flowers, making it a flowering plant.
(b) W [1]
Explanation: W is a mushroom (fungus) which reproduces by spores.
(c) Both are animals / Both have backbones (vertebrates) / Both breathe using lungs or gills / Both reproduce by laying eggs [1]
Explanation: Y (bird) and Z (fish) are both animals. Accept any valid similarity.
(d) W is a fungus (mushroom) while X is a flowering plant / W reproduces by spores while X reproduces by seeds / W cannot make its own food while X can make its own food [1]
Explanation: Any valid difference between fungus and flowering plant.
Question 12 [4 marks]
| Flowering Plants | Non-flowering Plants | Fungi | Bacteria |
|---|---|---|---|
| Hibiscus, Rose plant | Moss, Fern, Bird's nest fern | Yeast, Mould | Bacteria |
Marking: 0.5 marks each correct placement (8 items × 0.5 = 4 marks)
Explanation:
- Flowering plants: Hibiscus, Rose plant (reproduce by seeds, have flowers)
- Non-flowering plants: Moss, Fern, Bird's nest fern (reproduce by spores, no flowers)
- Fungi: Yeast, Mould (decomposers, reproduce by spores)
- Bacteria: Bacteria (microscopic, single-celled)
Question 13 [4 marks]
(a) A [1]
Explanation: Butterfly has 6 legs (insect) and has wings → Group A.
(b) B [1]
Explanation: Grasshopper has 6 legs (insect) but no wings (or wings not for flying in young stages) → Group B. Note: Adult grasshoppers have wings, but in primary classification, grasshoppers are often used as wingless insects. If student answers A with justification, accept.
(c) Have hair/fur / Mammals / Give birth to young alive / Feed young with milk [1]
Explanation: Group C branches from "Has hair/fur? Yes" - these are mammals.
(d) Live in water and have gills / Fish / Breathe through gills / Lay eggs in water [1]
Explanation: Group E branches from "Live in water and have gills? Yes" - these are fish.
Question 14 [4 marks]
(a) Non-flowering plants / Ferns and mosses [1]
Explanation: The organism has roots, stem, leaves (plant), is green (chlorophyll), no flowers, reproduces by spores → non-flowering plant.
(b) Fern / Moss / Bird's nest fern [1]
Explanation: Any example of non-flowering plant that reproduces by spores.
(c) Non-flowering plants reproduce by spores while flowering plants reproduce by seeds / Non-flowering plants do not have flowers while flowering plants have flowers [1]
Explanation: Key difference in reproduction method.
(d) It has roots, stem and leaves / It is green and contains chlorophyll / It makes its own food / Fungi do not have roots, stem, leaves and cannot make their own food [1]
Explanation: Plants have plant parts and are autotrophs; fungi lack true roots/stem/leaves and are heterotrophs.
Question 15 [4 marks]
(a) P and S [1]
Explanation: Plants make their own food (have chlorophyll). P and S both have "Makes own food = Yes" and "Has chlorophyll = Yes".
(b) Q [1]
Explanation: Bacteria are microscopic, cannot make own food, reproduce by spores (binary fission). Q matches: No own food, Yes spores, No chlorophyll, Yes microscopic.
(c) R [1]
Explanation: Fungi (mould/yeast) cannot make own food, reproduce by spores, no chlorophyll. R is not microscopic (mushroom/mould visible), so R = fungus. Q is microscopic (yeast/bacteria), but Q is bacteria.
(d) S [1]
Explanation: Ferns make own food (Yes), reproduce by spores (Yes), have chlorophyll (Yes), not microscopic (No). S matches all.
Section C: Open-Ended Questions (20 marks)
Question 16 [5 marks]
(a) Pupa (Chrysalis) [1]
Explanation: The stage between caterpillar and adult butterfly is the pupa.
(b) Caterpillar (Larva) stage. The caterpillar eats leaves voraciously to grow, causing damage to plants. [2]
Marking: 1 mark for identifying caterpillar, 1 mark for explanation (eats leaves/grows rapidly).
Explanation: Caterpillars are the feeding stage; they consume large amounts of plant material.
(c) Young (caterpillar) has no wings, adult has wings / Young crawls, adult flies / Young eats leaves, adult feeds on nectar / Different body shape [1]
Explanation: Any valid difference between larva and adult butterfly.
(d) Mosquito / Beetle / Fly / Bee / Ant / Wasp / Moth [1]
Explanation: These insects undergo complete metamorphosis (egg → larva → pupa → adult).
Question 17 [5 marks]
(a) Group A: Flowering plants [1]
Group B: Non-flowering plants [1]
Explanation: Group A reproduces by seeds (flowering plants). Group B reproduces by spores but makes own food (non-flowering plants).
(b) Both make their own food / Both have roots, stem and leaves / Both are plants / Both contain chlorophyll [1]
Explanation: Both Group B (non-flowering plants) and Group D (fungi) - wait, Group D is fungi which DON'T make own food. Correction: Similarity between Group B and Group D? Actually Group B = non-flowering plants (make food), Group D = fungi (don't make food). Let me re-read table.
Correction: Group B: Make own food, reproduce by spores. Group D: Cannot make own food, reproduce by spores.
Similarity: Both reproduce by spores [1]
Explanation: This is the only shared characteristic in the table.
(c) Group C is microscopic (bacteria) while Group D is not microscopic (mushroom, mould) / Group C are bacteria while Group D are fungi [1]
Explanation: Key difference is size/visibility.
(d) D [1]
Explanation: Yeast is a fungus, cannot make own food, reproduces by spores, not microscopic (visible as colonies) → Group D.
Question 18 [5 marks]
(a) To find out if yeast needs water to grow. [1]
Explanation: The investigation compares yeast with water (Set-up A) and without water (Set-up B).
(b) Set-up B. It has everything except water (no water added), so it shows what happens without water. [2]
Marking: 1 mark for identifying Set-up B, 1 mark for explanation (lacks water/only variable changed).
Explanation: Control set-up lacks the variable being tested (water) while keeping all other conditions same.
(c) Yeast needs water to grow / Water is necessary for yeast growth. [1]
Explanation: Balloon inflated in A (yeast respired, produced CO₂) but not in B (no water, no respiration/growth).
(d) Warmth / Suitable temperature / Food (sugar) / Air (oxygen for some yeast) / Time [1]
Explanation: Yeast needs warmth (optimal ~35°C), food source (sugar), and for some types, oxygen. The investigation already provided sugar and warmth.
Question 19 [5 marks]
(a) 1. Cell wall [1]
2. Chloroplast [1]
Explanation: Plant cells have cell wall (rigid structure) and chloroplasts (photosynthesis). Animal cells lack both. Large vacuole also acceptable.
(b) Contains chlorophyll to trap light energy for photosynthesis / Makes food for the plant [1]
Explanation: Chloroplasts are the site of photosynthesis where light energy is converted to chemical energy.
(c) Animals do not make their own food / Animals obtain food by eating other organisms / Animals are heterotrophs [1]
Explanation: Chloroplasts are for photosynthesis (making food). Animals are consumers, not producers.
(d) Controls all activities in the cell / Contains genetic material (DNA) / Controls cell division [1]
Explanation: Nucleus is the control centre of the cell in both plant and animal cells.
Question 20 [5 marks]
(a) Bacteria help us digest food / Bacteria used to make yoghurt and cheese / Bacteria in intestines help digestion [1]
Explanation: From passage: "bacteria in our intestines help us digest food, and bacteria are used to make yoghurt and cheese."
(b) Mould grows on damp food and causes food spoilage / Some fungi cause diseases / Food spoilage [1]
Explanation: From passage: "Mould grows on damp food and can cause food spoilage."
(c) Viruses can only reproduce inside living cells / Viruses are the smallest microorganisms / Viruses are not cells [1]
Explanation: From passage: "Viruses are the smallest microorganisms. They can only reproduce inside living cells."
(d) Table completion: [2 marks - 0.5 each]
| Type of Microorganism | Example | Use / Harm |
|---|---|---|
| Bacteria | Lactobacillus / Yoghurt bacteria / Bacteria | Make yoghurt |
| Fungi (Yeast) | Yeast / Baker's yeast | Make bread rise |
| Viruses | Coronavirus / SARS-CoV-2 / COVID-19 virus | Cause COVID-19 |
Explanation: Any valid example for each type. Bacteria for yoghurt: Lactobacillus. Yeast for bread: Baker's yeast/Saccharomyces. Virus for COVID-19: Coronavirus/SARS-CoV-2.
End of Answer Key
Total Marks: 60