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Primary 5 Science Life Cycles Quiz
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Questions
Primary 5 Science Quiz - Life Cycles
Name: _______________________ Class: _______ Date: _______
Duration: 40 minutes | Total Marks: 40 marks
Instructions:
- Answer all questions.
- Write your answers in the spaces provided.
- Read each question carefully before answering.
Section A: Multiple Choice (Questions 1–8, 8 marks)
Choose the correct answer and write its letter (A, B, C, or D) in the brackets.
1. Which of the following is the correct order of stages in the life cycle of a butterfly?
A. Egg → Pupa → Larva → Adult
B. Egg → Larva → Pupa → Adult
C. Egg → Adult → Larva → Pupa
D. Larva → Egg → Pupa → Adult
Answer: ( ) [1 mark]
2. During pollination in flowering plants, pollen grains are transferred from the
A. stigma to the ovary.
B. anther to the stigma.
C. ovule to the petals.
D. style to the ovary.
Answer: ( ) [1 mark]
3. The diagram below shows the life cycle of a fern.
<image_placeholder> id: Q3-fig1 type: diagram linked_question: Q3 description: Life cycle of a fern showing spore, prothallus, young fern, and adult fern stages in a cycle labels: spore, prothallus (small heart-shaped structure), young fern, adult fern with sori, arrows showing cycle direction values: none must_show: sori on underside of adult fern leaves, arrow from adult fern to spore, arrow from spore to prothallus, arrow from prothallus to young fern, arrow from young fern to adult fern </image_placeholder>
Ferns reproduce using
A. seeds.
B. spores.
C. flowers.
D. fruits.
Answer: ( ) [1 mark]
4. A farmer wants to grow many new tomato plants quickly that are identical to a healthy parent plant. The best method would be
A. growing from seeds produced by pollination.
B. taking stem cuttings from the parent plant.
C. waiting for flowers to develop and produce seeds.
D. cross-pollinating with a different tomato variety.
Answer: ( ) [1 mark]
5. The table below shows information about three animals.
| Animal | Number of stages in life cycle | Environment of early development |
|---|---|---|
| P | 4 | Water |
| Q | 3 | Land |
| R | 4 | Land |
Which of the following correctly identifies animals P, Q, and R?
A. P: mosquito, Q: chicken, R: butterfly
B. P: frog, Q: butterfly, R: mosquito
C. P: grasshopper, Q: frog, R: chicken
D. P: butterfly, Q: grasshopper, R: frog
Answer: ( ) [1 mark]
6. In the human reproductive system, fertilisation normally takes place in the
A. ovary.
B. vagina.
C. fallopian tube.
D. uterus (womb).
Answer: ( ) [1 mark]
7. The diagram shows a flower with its parts labelled.
<image_placeholder> id: Q7-fig1 type: diagram linked_question: Q7 description: Longitudinal section of a typical flower showing reproductive parts labels: A (tip of female part), B (male part), C (ovary at base), D (petal) values: none must_show: complete flower with sepals, petals, stamens (male), and pistil/carpel (female); label A at stigma, label B at anther, label C at ovary, label D at petal; arrow showing pollen tube growth path </image_placeholder>
Which labelled part produces pollen grains?
A. A
B. B
C. C
D. D
Answer: ( ) [1 mark]
8. Germination occurs when
A. pollen fuses with the ovule.
B. a seed develops into a young plant.
C. a fruit develops from a flower.
D. spores are released from a plant.
Answer: ( ) [1 mark]
Section B: Fill in the Blanks and Short Answer (Questions 9–14, 12 marks)
9. Complete the sentences about the life cycle of a flowering plant. [2 marks]
(a) Pollen grains are produced in the _________________________ which is part of the male reproductive organ called the _________________________. [1 mark]
(b) After fertilisation, the _________________________ develops into a seed and the _________________________ develops into a fruit. [1 mark]
10. The diagram shows the life cycle of a mosquito.
<image_placeholder> id: Q10-fig1 type: diagram linked_question: Q10 description: Life cycle of mosquito showing four stages: egg, larva, pupa, adult labels: Stage W (eggs on water surface), Stage X (larva in water), Stage Y (pupa in water), Stage Z (flying adult mosquito) values: none must_show: all four stages clearly distinct; eggs as cluster on water; larva as wriggler in water with siphon tube; pupa as comma-shaped at water surface; adult with wings and long legs; arrows indicating cycle progression </image_placeholder>
(a) Identify the stages labelled W, X, Y, and Z. [2 marks]
W: _________________________
X: _________________________
Y: _________________________
Z: _________________________
(b) Why is the mosquito's life cycle considered to have complete metamorphosis? [1 mark]
11. The diagram shows the human female reproductive system.
<image_placeholder> id: Q11-fig1 type: diagram linked_question: Q11 description: Simplified diagram of human female reproductive system labels: P (ovary), Q (fallopian tube/oviduct), R (uterus/womb), S (vagina) values: none must_show: two ovaries, fallopian tubes leading to uterus, pear-shaped uterus, vagina below; labels P, Q, R, S clearly marked; eggs shown traveling from ovary through tube to uterus </image_placeholder>
(a) Name the part labelled Q. [1 mark]
(b) Explain why it is important that fertilisation occurs at Q rather than at R. [2 marks]
12. Study the table about different methods of plant reproduction.
| Method | Description | Example plant |
|---|---|---|
| A | Seeds produced after pollination and fertilisation | Apple tree |
| B | Small plant grows from a bud on the parent plant | Spider plant |
| C | A piece of stem or leaf cut from parent grows into new plant | Begonia |
| D | Underground stem grows horizontally and produces new shoots | Ginger |
(a) Which method (A, B, C, or D) involves sexual reproduction? [1 mark]
(b) Explain your answer to part (a). [1 mark]
13. The diagram shows two ways that seeds can be dispersed.
<image_placeholder> id: Q13-fig1 type: diagram linked_question: Q13 description: Two seed dispersal methods shown side by side labels: Seed X (hooked/spiny seed structure), Seed Y (winged/flat seed with wing-like extension) values: none must_show: Seed X with small hooks or spines for animal attachment; Seed Y with large flat wing for wind dispersal; arrows showing direction of dispersal; brief labels of dispersal methods </image_placeholder>
(a) Name the method of dispersal for Seed X and Seed Y. [2 marks]
Seed X: _________________________
Seed Y: _________________________
(b) For Seed X, explain how its structure helps it to be dispersed. [1 mark]
14. A student observed that a bean seed had germinated and grown into a seedling. Complete the table to show three conditions needed for germination and why each condition is necessary. [2 marks]
| Condition needed | Why it is necessary |
|---|---|
| (a) _________________________ | _________________________ |
| (b) _________________________ | _________________________ |
| (c) _________________________ | _________________________ |
(Note: You need to write two conditions and explanations for 2 marks; the table shows space for three for completeness)
Section C: Application and Reasoning (Questions 15–20, 20 marks)
15. The diagram shows the life cycles of a butterfly and a grasshopper.
<image_placeholder> id: Q15-fig1 type: diagram linked_question: Q15 description: Two life cycle diagrams shown side by side for comparison labels: Butterfly cycle (Egg → Larva → Pupa → Adult); Grasshopper cycle (Egg → Nymph → Adult); stages shown with drawings values: none must_show: Butterfly with 4 distinct stages including pupa/cocoon; grasshopper with 3 stages showing nymph resembling small adult; nymph stages showing gradual growth and wing development; arrows between stages; labels clearly identifying each stage </image_placeholder>
(a) The butterfly undergoes _________________________ metamorphosis, while the grasshopper undergoes _________________________ metamorphosis. [2 marks]
(Fill in either "complete" or "incomplete" for each.)
(b) State two differences between the life cycle of a butterfly and a grasshopper. [2 marks]
16. A flower has the following features: bright red petals, sweet nectar, and a sticky stigma.
(a) Suggest two ways that this flower is adapted for pollination. [2 marks]
(b) Explain why it is important for seeds to be dispersed far away from the parent plant. [2 marks]
17. The diagram shows a seed with its parts labelled.
<image_placeholder> id: Q17-fig1 type: diagram linked_question: Q17 description: Longitudinal section of a bean seed showing internal structure labels: A (seed coat/testa), B (cotyledon), C (plumule/embryo shoot), D (radicle/embryo root), E (micropyle) values: none must_show: outer seed coat, two large cotyledons, small plumule between cotyledons, radicle at base, small hole (micropyle); all labels clearly marked; section view showing internal arrangement </image_placeholder>
(a) Name the parts labelled B and C. [2 marks]
B: _________________________
C: _________________________
(b) Explain the function of part B during germination. [2 mark]
(c) After germination, which part labelled C or D develops into the root system of the new plant? [1 mark]
18. The graph shows the height of two plant seedlings over three weeks. Both seedlings were given water and air, but Seedling X was kept in a dark cupboard while Seedling Y was placed on a sunny window ledge.
<image_placeholder> id: Q18-fig1 type: graph linked_question: Q18 description: Line graph showing seedling growth over three weeks under different light conditions labels: x-axis "Time (weeks)" (0, 1, 2, 3), y-axis "Height of seedling (cm)" (0 to 15); Line X (dark), Line Y (light) values: Line X: week 0=0, week 1=3, week 2=8, week 3=12 (tall, pale, thin); Line Y: week 0=0, week 1=2, week 2=5, week 3=8 (shorter, green, sturdy) must_show: two distinct lines with different colours/patterns; clear axis labels with units; legend identifying Line X (dark) and Line Y (light); plotted points connected; title "Growth of Seedlings Under Different Light Conditions" </image_placeholder>
(a) Describe two differences between Seedling X and Seedling Y after three weeks. [2 marks]
(b) Explain why Seedling X grew taller than Seedling Y even though it was in the dark. [2 marks]
19. The diagram shows the life cycle of a frog.
<image_placeholder> id: Q19-fig1 type: diagram linked_question: Q19 description: Life cycle of a frog showing aquatic and terrestrial stages labels: Stage 1 (eggs in jelly mass in water), Stage 2 (tadpole with gills and tail), Stage 3 (tadpole with hind legs), Stage 4 (tadpole with front and hind legs, shorter tail), Stage 5 (young frog), Stage 6 (adult frog) values: none must_show: eggs as cluster/jelly mass; tadpole stages showing gradual leg development and tail shortening; gills visible on early tadpole; lungs implied in later stages; adult frog on land/water edge; arrows showing progression; all six stages numbered and labelled </image_placeholder>
(a) State two ways that a tadpole (Stage 2) is different from an adult frog (Stage 6). [2 marks]
(b) Explain why the tadpole stage must develop in water. [2 marks]
(c) A pond dried up during a drought when many frog eggs had just been laid. Predict what would happen to these eggs and explain your answer. [2 marks]
20. A scientist wants to investigate which method of vegetative reproduction produces new strawberry plants fastest. She uses three methods: runners, stem cuttings, and seeds. She measures the time taken for each method to produce a plant that bears fruit.
(a) Suggest two variables that the scientist should keep constant in this investigation. [2 marks]
(b) Explain why growing strawberries from runners might be better than growing from seeds for a farmer who needs plants quickly. [2 marks]
(c) All the new strawberry plants grown from runners are identical to the parent plant. Explain why this is an advantage for the farmer. [2 marks]
END OF QUIZ
Answers
Primary 5 Science Quiz - Life Cycles (Answer Key)
Total Marks: 40 marks
Section A: Multiple Choice (Questions 1–8)
1. B — Egg → Larva → Pupa → Adult [1 mark]
Explanation: The life cycle of a butterfly has four stages called complete metamorphosis. The larva (caterpillar) hatches from the egg, eats and grows, then forms a pupa (chrysalis) where it transforms into an adult butterfly. This is different from incomplete metamorphosis which has only three stages and no pupa stage.
2. B — anther to the stigma [1 mark]
Explanation: Pollination is the transfer of pollen grains from the anther (male part) to the stigma (female part). The anther is at the top of the filament and produces pollen. The stigma is at the top of the style and is sticky to catch pollen. After pollination, fertilisation can occur when the pollen tube grows down to the ovary.
3. B — spores [1 mark]
Explanation: Ferns do not produce flowers, fruits, or seeds. They reproduce by producing spores in structures called sori (singular: sorus) on the underside of their fronds (leaves). When spores land in a damp place, they grow into a small heart-shaped structure called a prothallus, which produces male and female cells for fertilisation. This is different from seed-producing plants like flowering plants and conifers.
4. B — taking stem cuttings from the parent plant [1 mark]
Explanation: Stem cuttings are a method of asexual (vegetative) reproduction. The new plants produced will be genetically identical to the parent plant because they come directly from the parent's body tissue, not from seeds formed by sexual reproduction. Growing from seeds (options A and C) involves sexual reproduction with pollination and fertilisation, which produces variation. Cross-pollination (option D) deliberately creates different combinations of characteristics.
5. A — P: mosquito, Q: chicken, R: butterfly [1 mark]
Explanation: Mosquitoes have four stages (egg, larva, pupa, adult) with early stages in water — complete metamorphosis. Chickens have three stages (egg, chick, adult) with development on land. Butterflies have four stages (egg, larva, pupa, adult) with all stages on land. Frogs have 3 stages (egg, tadpole, adult) with early development in water, not 4 stages. Grasshoppers have incomplete metamorphosis (3 stages: egg, nymph, adult) with development on land.
6. C — fallopian tube [1 mark]
Explanation: Fertilisation occurs when a male reproductive cell (sperm) fuses with a female reproductive cell (egg) in the fallopian tube (also called the oviduct). The fertilised egg then travels to the uterus where it develops into a baby. The ovary produces eggs, the uterus is where the baby develops, and the vagina is the birth canal.
7. B — B [1 mark]
Explanation: Part B is the anther, which is the top part of the stamen (the male reproductive organ). The anther produces pollen grains which contain the male reproductive cells. Part A is the stigma (female, receives pollen), part C is the ovary (female, contains ovules), and part D is the petal (attracts pollinators).
8. B — a seed develops into a young plant [1 mark]
Explanation: Germination is the process where a seed begins to grow and develop into a new plant. It requires water, air (oxygen), and a suitable temperature. Fertilisation (option A) is the fusion of male and female reproductive cells. Fruit development (option C) happens after fertilisation in flowering plants. Spore release (option D) is how ferns and some other plants reproduce, not germination.
Section B: Fill in the Blanks and Short Answer (Questions 9–14)
9. (a) anther; stamen [1 mark]
Explanation: The stamen is the male reproductive organ of a flower. It has two parts: the filament (stalk) and the anther (top part that produces pollen grains). This is the first step in sexual reproduction in flowering plants.
(b) ovule; ovary [1 mark]
Explanation: After pollination and fertilisation, the ovule (which contains the female reproductive cell) develops into a seed. The ovary (which contains the ovules) develops into a fruit that protects the seeds and helps in seed dispersal. This is why fruits contain seeds.
10. (a) W: egg; X: larva; Y: pupa; Z: adult [2 marks]
Marking: 1 mark for 2–3 correct answers; 2 marks for all 4 correct. Deduct for incorrect spellings if meaning is unclear.
(b) The mosquito's life cycle has four distinct stages (egg → larva → pupa → adult) with a pupa stage where the larva undergoes a complete change in body form. [1 mark]
Explanation: Complete metamorphosis means the young (larva) looks completely different from the adult and there is a non-feeding, resting pupa stage in between where the body is reorganised. Incomplete metamorphosis (like in grasshoppers) has no pupa stage — the nymph looks like a small adult.
11. (a) Fallopian tube / Oviduct [1 mark]
Explanation: The fallopian tube (also called oviduct) is the tube that carries the egg from the ovary to the uterus. This is where fertilisation normally occurs.
(b) Fertilisation must occur at Q (fallopian tube) because if it occurred at R (uterus), the fertilised egg would not be able to implant and develop properly. / The fallopian tube provides the right environment for the sperm to meet the egg, and the fertilised egg needs time to develop and travel to the uterus where it can implant in the lining. [2 marks]
Mark breakdown: 1 mark for explaining that the fallopian tube is where sperm and egg meet; 1 mark for explaining that the fertilised egg then travels to the uterus for development OR that the uterus lining prepares for implantation.
Explanation: The egg is released from the ovary (P) and enters the fallopian tube. Sperm travel up to meet it here. The fertilised egg takes several days to reach the uterus, during which it begins dividing. By the time it reaches the uterus, it is ready to implant in the thickened lining.
12. (a) A [1 mark]
(b) Method A involves seeds, which are produced after pollination (transfer of pollen from male to female part) and fertilisation (fusion of male and female reproductive cells). These two processes are part of sexual reproduction which involves two parents and mixing of genetic material. [1 mark]
Explanation: Sexual reproduction in plants involves flowers, pollination, fertilisation, and seed production. The other methods (B, C, D) are all asexual/vegetative reproduction where new plants grow from parts of one parent plant without seeds, so they are genetically identical to the parent.
13. (a) Seed X: by animals / animal dispersal; Seed Y: by wind / wind dispersal [2 marks]
(b) The hooks/spines on Seed X can attach to the fur or feathers of animals. When animals move, they carry the seeds to new locations. [1 mark]
Explanation: Seed X has structures that hook onto animals (like burdock or love grass). Seed Y has a wing or parachute structure that allows it to be carried by wind (like maple or dandelion seeds). Being dispersed away from the parent plant reduces competition for light, water, and nutrients, and allows colonisation of new areas.
14. Any two from: [2 marks]
| Condition needed | Why it is necessary |
|---|---|
| Water | To soften the seed coat and activate enzymes that digest stored food for the growing embryo |
| Air (oxygen) | For respiration to release energy for growth of the embryo |
| Suitable temperature | For enzymes to work best for the chemical reactions of germination |
Mark breakdown: 1 mark for each correct condition with valid explanation (max 2 marks).
Common mistake: Students often write "sunlight" as a condition, but seeds can germinate in darkness. Light is needed later for photosynthesis by the seedling, not for germination itself.
Section C: Application and Reasoning (Questions 15–20)
15. (a) complete; incomplete [2 marks]
Mark breakdown: 1 mark each.
(b) Any two valid differences: [2 marks]
- The butterfly has a pupa stage, but the grasshopper does not.
- The grasshopper nymph looks like a small adult, but the butterfly larva (caterpillar) looks completely different from the adult.
- The butterfly larva lives in a different habitat/eats different food from the adult; grasshopper nymph eats same food as adult.
- The grasshopper nymph gradually develops wings; the butterfly wings develop inside the pupa.
Mark breakdown: 1 mark for each clear, correct difference.
Explanation: Complete metamorphosis (butterfly, moth, beetle, fly) has four stages with a dramatic change in body form. Incomplete metamorphosis (grasshopper, cockroach, dragonfly) has three stages where the young (nymph) resembles the adult but lacks fully developed wings and reproductive organs.
16. (a) Bright red petals attract insects/bees/birds that pollinate the flower. [1 mark]
The sweet nectar attracts pollinators which come to drink it and pick up/deliver pollen. [1 mark]
Explanation: These are adaptations for insect or bird pollination. Bright colours are visible signals, nectar is food reward, and a sticky stigma helps pollen grains adhere when pollinators visit.
(b) If seeds fall and grow near the parent plant, they would compete for limited resources like light, water, and minerals. [1 mark]
Being dispersed far away allows seeds to grow in new areas with less competition and more resources, increasing their chance of survival. [1 mark]
Explanation: This is important for the survival of the species. Different dispersal methods (wind, water, animal, explosive) have evolved to help seeds reach suitable habitats away from the parent.
17. (a) B: cotyledon; C: plumule / embryo shoot [2 marks]
Mark breakdown: 1 mark each. Accept "seed leaf" for cotyledon.
(b) The cotyledon stores food (starch) for the developing embryo. During germination, this stored food is broken down and provides energy for the embryo to grow until the seedling can make its own food by photosynthesis. [2 marks]
Mark breakdown: 1 mark for stating food storage; 1 mark for explaining it provides energy for growth before photosynthesis begins.
(c) D (the radicle) [1 mark]
Explanation: The radicle is the embryonic root. It grows downward into the soil to anchor the plant and absorb water and minerals. The plumule (C) grows upward to become the shoot system with leaves and stem.
18. (a) Any two valid differences: [2 marks]
- Seedling X is taller than Seedling Y after three weeks (12 cm vs 8 cm).
- Seedling X is pale/yellow while Seedling Y is green.
- Seedling X is thin and spindly while Seedling Y is sturdy/thick-stemmed.
- Seedling Y has more leaves / larger leaves than Seedling X.
Mark breakdown: 1 mark for each difference with data reference where appropriate. Must describe the visual characteristics, not just height.
(b) In darkness, Seedling X cannot photosynthesise to make food, so it grows tall quickly to try to reach light. [1 mark]
This is called etiolation — the plant uses stored energy from the seed to grow rapidly in height with a thin stem and small leaves, rather than growing sturdy and green like Seedling Y which can photosynthesise in light. [1 mark]
Explanation: This is a survival adaptation. Plants can detect light direction and will bend and stretch toward it (phototropism). In prolonged darkness, the seedling becomes etiolated — tall, pale, and weak — because it is searching for light rather than investing energy in chlorophyll production and sturdy growth.
19. (a) Any two valid differences: [2 marks]
- The tadpole has gills for breathing in water; the adult frog has lungs for breathing air.
- The tadpole has a tail for swimming; the adult frog has four legs for hopping and swimming.
- The tadpole lives entirely in water; the adult frog lives on land and water.
- The tadpole eats algae/plants; the adult frog eats insects/small animals.
- The tadpole has no legs; the adult frog has four legs.
Mark breakdown: 1 mark for each clear, correct difference.
(b) The tadpole has gills for breathing underwater, which need to be surrounded by water to extract dissolved oxygen. [1 mark]
The tadpole's body is not adapted for life on land — it has no legs for movement and no lungs developed yet for breathing air. [1 mark]
Explanation: This is an example of metamorphosis where the body structure completely changes. The tadpole gradually develops lungs, legs, and loses its tail as it transforms into an adult frog that can live on land.
(c) The eggs would dry out and die. [1 mark]
Frog eggs are laid in jelly masses that need water to keep them moist and provide oxygen. Without water, the jelly would dry out, the embryos would not get enough oxygen, and development would stop. [1 mark]
Explanation: Frog eggs do not have a protective shell like bird or reptile eggs. Their jelly coating absorbs water and allows gas exchange. This is why frogs must lay eggs in water, and their breeding is often triggered by rainfall.
20. (a) Any two valid constants: [2 marks]
- Same type/variety of strawberry plant used for all methods.
- Same amount of water given to all plants.
- Same temperature/light conditions for all plants.
- Same type of soil/pot size.
- Same time of year/starting time.
Mark breakdown: 1 mark for each valid controlled variable. Must be something that could actually affect the results and should be kept the same for fair testing.
(b) Runners are a form of vegetative/asexual reproduction, so the new plant is already partially developed and can grow faster. [1 mark]
Plants from runners skip the seed germination stage which takes time, and they already have roots and shoots starting to form, so they can bear fruit sooner than plants grown from seeds. [1 mark]
Explanation: Runners are horizontal stems that grow along the ground with new plantlets at nodes. These plantlets already have small roots and leaves, so they establish quickly when they touch soil. Seeds must first germinate, which involves activating enzymes, breaking down stored food, and slowly developing embryonic structures.
(c) All runner plants have the same desirable characteristics as the parent (same sweetness, size, disease resistance, etc.). [1 mark]
The farmer can be certain of the fruit quality and quantity, which is important for selling and predictability. There is no variation that might produce poor-quality fruit. [1 mark]
Explanation: Asexual reproduction produces clones — genetically identical organisms. This is valuable in farming and gardening to maintain consistent quality. Sexual reproduction (seeds) creates genetic variation which can be unpredictable, though it may occasionally produce improved varieties.
END OF ANSWER KEY