Feeding Relationships
Overview
Every organism needs energy, and that energy almost always traces back to the Sun. Plants capture light energy and lock it into glucose. Herbivores eat the plants. Carnivores eat the herbivores. At every step, most of the energy is used up rather than passed on, which is why food chains rarely have more than five links.
In this lesson you will learn the names ecologists give to each feeding level, build food chains and food webs, and explore three types of ecological pyramid. You will also discover why only about 10% of energy transfers from one trophic level to the next - a fact that shapes ecosystems worldwide.
Objectives
- Understand the names given to different trophic levels, including producers, primary, secondary and tertiary consumers and decomposers
- Understand the concepts of food chains, food webs, pyramids of number, pyramids of biomass and pyramids of energy transfer
- Understand the transfer of substances and energy along a food chain
- Understand why only about 10% of energy is transferred from one trophic level to the next
Mind map
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Flashcards
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Lesson Note
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Lesson Evaluation
Congratulations on completing the lesson on Feeding Relationships. Now that youve explored the key concepts and ideas, its time to put your knowledge to the test. This section offers a variety of practice questions designed to reinforce your understanding and help you gauge your grasp of the material.
You will encounter a mix of question types, including multiple-choice questions, short answer questions, and essay questions. Each question is thoughtfully crafted to assess different aspects of your knowledge and critical thinking skills.
Use this evaluation section as an opportunity to reinforce your understanding of the topic and to identify any areas where you may need additional study. Don't be discouraged by any challenges you encounter; instead, view them as opportunities for growth and improvement.
- Which trophic level contains producers? A) Level 2 B) Level 1 C) Level 3 D) Level 4 Answer: B
- Approximately what percentage of energy is transferred from one trophic level to the next? A) 50% B) 90% C) 10% D) 100% Answer: C
- Which type of ecological pyramid is always pyramid-shaped? A) Pyramid of numbers B) Pyramid of energy C) Both A and B D) Neither A nor B Answer: B
- In a food chain, the arrows show: A) The direction predators move B) The direction of energy transfer C) The size of organisms D) The habitat of organisms Answer: B
- What is the main reason energy is lost between trophic levels? A) Photosynthesis B) Respiration C) Reproduction D) Growth Answer: B
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