B18 - Organisms & their environment Flashcards
What are consumers? [1]
An organism that gets its energy by feeding on other organisms.
What is a trophic level? [1]
The position of an organism in a food chain and food web.
What are decomposers? [2]
Organisms that break down organic substances outside their bodies, releasing nutrients from them that other organisms can use.
What are producers? [1]
An organism that makes its own organic nutrients, generally using energy from sunlight, through photosynthesis.
What is a herbivore? [1]
An animal that gets its energy by eating plants.
What is a carnivore? [1]
An animal that gets its energy by eating other animals.
What is an omnivore? [1]
An animal that gets its energy by eating both animals and plants.
What is a primary consumer? [2]
- Herbivores
- They eat or consume the producers.
What is a secondary consumer? [2]
- Carnivores
- These consume the primary consumers.
What is a tertiary consumer? [3]
- These eat the secondary consumers (carnivores).
- These are hunters that hunt, catch, kill their prey for food
- Top of the food chain as they are not normally killed by other animals.
What is a quaternary consumer? [1]
- They feed on tertiary consumers.
Where does all the energy in a food chain originally come from? [1]
The Sun
What ALWAYS starts the food chain? [1]
Plants = the producer
What do organisms tend to do? [2]
- Increase in size
- Decrease in number
How do humans impact food chains? [2]
- Overharvesting food species e.g. overgrazing of grass
- Introducing foreign species to habitat e.g. cane toad in Australia.
What are the effects of overharvesting food species? [3]
- Decrease in biodiversity
- Risk of extinction of a species
- Disrupts natural food chain of habitat
What are the effects of introducing foreign species to habitat? [3]
- Disrupts natural food chain
- Loss of habitat as foreign species take over
- No natural predators to control population of species
What does the law of conservation of energy state? [2]
- Energy cannot be created or destroyed
- It can only be changed from one form to another
What does a food chain show? [1]
The transfer of energy from one organism to another
In what form does energy enter the food chain? [1]
Light energy
What process converts light energy into chemical energy?
Photosynthesis
In what form is energy passed along the food chain? [1]
Chemical energy
In what form is energy released from the food chain? [1]
Heat energy
Only about what percentage of energy is passed on to the next trophic level? [1]
10%
How is energy lost from the food chain? [3]
- Heat from respiration
- Uneaten parts e.g. bones, teeth
- Egestion & excretion
Why are there usually no more than 5 trophic levels in a food chain? [2]
- Energy is lost at each trophic level
- So there is not enough left to support organisms at higher levels
Why is it more efficient for humans to be vegetarian? [2]
- Plants are lower down the food chain and so less energy has been lost
- More efficient to eat plants than animals
What is decomposition / decay? [1]
Break down of organic matter.
What is organic matter? [1]
Dead organisms or waste material from living things e.g. faeces, urine
What is a decomposer? [1]
Organisms that break down dead organic material.
What types of organisms are decomposers? [2]
- Bacteria
- Fungi
What do decomposers do? [3]
- They get energy from dead organisms and their waste
- Breakdown this organic matter to feed on it - causes decay
- Provides energy & nutrients for the decomposers
How do decomposers benefit the ecosystem? [1]
Surplus is released back into the soil to be taken out by plants.
What are the 7 processes involved in moving carbon? [7]
- Death
- Burning
- Respiration
- Feeding
- Photosynthesis
- Decay
- Burial and Sedimentation
What is the release of energy from fossil fuels called? [1]
Burning
What is the release of energy in living cells which produce carbon dioxide called? [1]
Respiration
What is consumers taking in food called? [1]
Feeding
What is the process by which a green plant makes its own food called? [1]
Photosynthesis
What is the rotting down of dead organisms called? [1]
Decay
What is the formation of fossils called? [1]
Burial and Sedimentation
What is the word equation for photosynthesis? [2]
Carbon Dioxide + Water —-> Glucose + Oxygen
What is the word equation for respiration? [2]
Glucose + Oxygen —-> Carbon Dioxide + Water
What is the word equation for combustion? [2]
Hydrocarbon fuel (fossil fuel) + Oxygen —-> Carbon Dioxide + Water
What causes decay? [1]
Bacteria and fungi breaking down dead material and animal waste
