Grade 6 Science Worksheet: 20 Objective and 10 Subjective Questions on Food Chain and Food Web

Instructions

Read each question carefully and answer to the best of your ability. For multiple-choice questions, circle the letter of the best answer. For the other sections, write your answers in the space provided.

Part 1: Objective Questions

1. What is the primary source of energy for almost all life on Earth?
   • A. Water
   • B. The Sun
   • C. The Moon
   • D. Plants
2. An organism that makes its own food, usually through photosynthesis, is called a:
   • A. Consumer
   • B. Decomposer
   • C. Producer
   • D. Scavenger
3. In the food chain: Grass → Rabbit → Fox, the rabbit is the:
   • A. Producer
   • B. Primary Consumer
   • C. Secondary Consumer
   • D. Decomposer
4. Which of the following is an example of a carnivore?
   • A. Deer
   • B. Cow
   • C. Lion
   • D. Rabbit
5. What do the arrows in a food chain or food web represent?
   • A. The direction of animal migration
   • B. The flow of energy from one organism to another
   • C. The life cycle of an organism
   • D. Who eats whom, pointing from predator to prey
6. A complex network of interconnected food chains in an ecosystem is called a:
   • A. Food pyramid
   • B. Food line
   • C. Food web
   • D. Energy cycle
7. An animal that eats both plants and animals is known as a(n):
   • A. Herbivore
   • B. Carnivore
   • C. Producer
   • D. Omnivore
8. Which of these organisms is a decomposer?
   • A. Grass
   • B. Mouse
   • C. Hawk
   • D. Mushroom
9. If a hawk eats a snake that has eaten a frog, the hawk is a:
   • A. Primary consumer
   • B. Secondary consumer
   • C. Tertiary consumer
   • D. Producer
10. What type of organism is always at the bottom, or the first level, of a food chain?
    • A. A herbivore
    • B. A carnivore
    • C. A decomposer
    • D. A producer

11. ____ Energy flows from a consumer to a producer.
12. ____ A food web shows only a single pathway for energy flow.
13. ____ Decomposers are important for returning nutrients to the soil.
14. ____ A secondary consumer eats plants directly.
15. ____ Some humans can be classified as omnivores.

Word Bank: sun, herbivore, energy, decomposers, producers

16. An animal that only eats plants is called a(n) ________________________.
17. A food chain shows how ________________________ is passed from one organism to another.
18. Plants are called ________________________ because they create their own food.
19. Fungi and bacteria are important ________________________ that break down dead material.
20. The ultimate source of energy for most food webs is the ________________________.

Part 2: Subjective Questions

1. What is the main difference between a food chain and a food web?
   
   
   
2. Draw a simple food chain that includes four organisms. Label the producer, primary consumer, secondary consumer, and tertiary consumer.
   
   
   
   
3. Why are producers, like plants, so important for an entire ecosystem?
   
   
   
4. Imagine a forest food web where owls eat mice, and mice eat seeds. If a disease suddenly wiped out most of the owl population, what would likely happen to the population of mice? Why?
   
   
   
5. What is an omnivore? Give an example of an animal that is an omnivore.
   
   
   
6. What is the role of a decomposer in a food web? Give one example.
   
   
   
7. Explain why a food web is a more accurate representation of an ecosystem than a food chain.
   
   
   
8. What is an animal called if it only eats meat? Give an example.
   
   
   
9. Consider the following food chain: Algae → Shrimp → Fish → Seal. Which organism is the secondary consumer?
   
   
   
10. What happens to the energy as it moves up from one level of the food chain to the next? Does all of it get transferred?
    
    
    

Answer Key

Part 1: Objective Questions

1. B. The Sun
2. C. Producer
3. B. Primary Consumer
4. C. Lion
5. B. The flow of energy from one organism to another
6. C. Food web
7. D. Omnivore
8. D. Mushroom
9. C. Tertiary consumer
10. D. A producer
11. F (False)
12. F (False)
13. T (True)
14. F (False)
15. T (True)
16. herbivore
17. energy
18. producers
19. decomposers
20. sun

Part 2: Subjective Questions (Sample Answers)

1. A food chain shows a single path of energy flow in an ecosystem. A food web shows many interconnected food chains and how energy can flow along multiple paths.
2. (Example drawing answer) Sunflower (Producer) → Bee (Primary Consumer) → Spider (Secondary Consumer) → Bird (Tertiary Consumer). The labels should correctly identify each organism's role.
3. Producers are important because they are the foundation of the food web. They create their own food using energy from the sun, and all other organisms (consumers) depend on them directly or indirectly for energy.
4. The mouse population would likely increase. With fewer owls (predators) to eat them, more mice would survive and reproduce.
5. An omnivore is an animal that eats both plants and other animals. An example is a bear (eats berries and fish) or a raccoon.
6. A decomposer breaks down dead plants and animals, returning important nutrients to the soil, which helps producers grow. An example is fungi or bacteria.
7. A food web is more accurate because most animals eat more than one type of food and are eaten by more than one type of predator. A food web shows these complex relationships, while a food chain only shows one path.
8. An animal that only eats meat is called a carnivore. An example is a tiger, wolf, or eagle.
9. The fish is the secondary consumer because it eats the shrimp (the primary consumer).
10. As energy moves up the food chain, a large amount of it is lost at each level (used for life processes like moving and keeping warm). Not all of the energy gets transferred; only about 10% is passed on to the next level.