Feeding RelationshipsEdexcel IGCSE Biology: Flashcards
Card 1 of 140 of 14 known
Question
What is a producer?
Tap or press Space to reveal
Tap card or press Space to flip
See all 14 cards
- What is a producer?
- An organism, usually a green plant or alga, that makes its own food by photosynthesis and forms the base of a food chain.
- What is a primary consumer?
- An animal (herbivore) that eats producers directly.
- What is a secondary consumer?
- An animal that eats primary consumers.
- What is the role of decomposers in a food chain?
- They break down dead organisms and waste at every trophic level, releasing nutrients back into the ecosystem.
- What does a food chain show?
- The transfer of energy from one organism to the next, always starting with a producer, shown with arrows pointing towards the organism gaining the energy.
- What is a food web?
- A network of interconnected food chains showing all the feeding relationships in a habitat.
- What does a pyramid of biomass show?
- The total mass of living material at each trophic level in a food chain.
- Why is a pyramid of numbers sometimes not a true pyramid shape?
- Because a small number of very large producers (e.g. one tree) can support a large number of small consumers (e.g. many insects).
- Why are pyramids of biomass and energy transfer almost always true pyramid shapes?
- Because biomass and energy both decrease at each successive trophic level.
- Approximately what percentage of energy is transferred from one trophic level to the next?
- About 10%.
- Name two reasons why energy is lost between trophic levels.
- Energy is lost as heat during respiration, and through movement, undigested material (faeces), and parts of organisms not eaten.
- Why do food chains rarely have more than four or five trophic levels?
- Because so much energy is lost at each level that there is not enough left to support further levels.
- What is transferred along a food chain besides energy?
- Substances/matter, such as carbon and nitrogen compounds, as one organism eats another.
- Which trophic level is a fox typically at, in the chain grass to rabbit to fox?
- Secondary consumer (it eats the rabbit, a primary consumer).