Hi guys, Welcome to the Advanced Video Search Engine, and you are watching Ecosystems: Food Chains, Food Webs & Trophic Levels | A-level Biology | OCR, AQA, Edexcel. That video is uploaded by SnapRevise at 2019-07-18T13:32:22-07:00. We are promoting this video only for entertainment and educational purpose only. So, I hope you like & enjoy it. [QDUQePm_zPI]
| Name | Ecosystems: Food Chains, Food Webs & Trophic Levels | A-level Biology | OCR, AQA, Edexcel |
| Video Uploader | Video From SnapRevise |
| Upload Date | This Video Uploaded At 18-07-2019 20:32:22 |
| Video Discription | Ecosystems: Food Chains, Food Webs & Trophic Levels in a Snap! Unlock the full A-level Biology course at http://bit.ly/2K1CT7J created by Adam Tildesley, Biology expert at SnapRevise and graduate of Cambridge University. SnapRevise is the UK’s leading A-level and GCSE revision & exam preparation resource offering comprehensive video courses created by A* Oxbridge tutors. Our courses are designed around the OCR, AQA, SNAB, Edexcel B, WJEC, CIE and IAL exam boards, concisely covering all the important concepts required by each specification. In addition to all the content videos, our courses include hundreds of exam question videos, where we show you how to tackle questions and walk you through step by step how to score full marks. Sign up today and together, let’s make A-level Biology a walk in the park! The key points covered in this video include: 1. Food Chains 2. Food Webs 3. Trophic levels Food Chains Organisms live with and eat other organisms in a given habitat. One organism may eat plants and then itself get eaten by another organism - this establishes a food chain. A food chain is the sequence of feeding interactions between organisms in a given habitat. The food chain can be comprised of several different organisms: 1. The first organism is the producer - this is an organism that makes its own food by photosynthesis e.g. grass. 2. The second organism is the primary consumer - this is an organism that eats plants/ producers, and so is a herbivore e.g. rabbit. 3. The third organism is the secondary consumer - these are organisms that feed on primary consumers e.g. wild cat 4. The fourth organism is the tertiary consumer - these are organisms that feed on secondary consumers e.g. lions. 5. The final organisms are decomposers- these are microorganisms that break down organism remains e.g. fungi and bacteria. Food Webs However, no group of organisms in a food chain are isolated as one feeding chain can feed into a larger food web. A food web is a system of independet and interlocking food chains in a given habitat or larger ecosystem. When an organism is part of a larger, complex food web, a change in one component can affect the balance of the entire feeding system. Trophic Levels As we have seen, feeding relationships are sequenced into food chains. Each level or link in the food chain is known as a trophic level. A trophic level describes the position of an organism in a food chain or web and describes its feeding relationship with other organisms. Summary The feeding sequence in a given habitat is known as a food chain A collection of interlocking food chains is called a food web Each level in these chains is known as a trophic level Different organism at different levels on the food chain and/or web have different names as consumers or as a producer The decomposer is not usually mentioned on the food chain/web QDUQePm_zPI |
| Category | Education |
| Tags | snaprevise | a-level | alevel | biology | alevel biology | ocr | aqa | snab | edexcel b | wjec | eduqas | ial | cie | Ecosystems: Food Chains | Food Webs & Trophic Levels | Food Chains | Food Webs | Trophic Levels |
