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25 Cards in this Set

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  • Back
The study of relationships between living organisms and between organisms and their environment.
A community and its abiotic environment.
A group of organisms of the same species who live in the same area at the same time.
A group of populations living and interacting with each other in an area.
A group of organisms which can interbreed and produce fertile offspring.
The environment in which a species normally lives or the location of living organism.
Organisms that use an external energy source to produce organic matter from inorganic raw materials.
They make their own food, so are also called producers.
Organisms that use the energy in organic matter, obtained from other organisms.
Detritivores feed on dead organic matter by ingesting it. Detritivores are a type of heterotroph.
Saprotrophs feed on dead organic matter by secreting digestive enzymes into it and absorbing the products of digestion.
Examples of saprotrophs are bread mould and mushrooms.
Saprotrophs are a type of heterotroph.
What is a food chain?
Food chains are sequences of trophic relationships. Each member in a food chain feeds on the previous one.
What is a food web?
A food web is a diagram showing all the feeding relationships in a commumity. They are often very complex.
What are trophic levels?
The position of an organism in a food chain is it's trophic level. Producer, primary consumer, secondary consumer and tertiary consumer are some trophic levels.
Is light important in communities? Why?
Yes, light is very important in almost all communites because almost all producers make organic matter by photosynthesis. All other organisms depend on producers, so without light, no producers would make organic matter, and all consumers would be unable to survive.
How does energy flow in a food chain?
Energy enters the food chain as light energy which is absorbed by producers. It passes through the food chain. Some of it is lost between trophic levels, this includes material that is not consumed and also heat loss due to cell respiration.
Is the transformation of energy efficient?
Energy transformations are not 100% efficient. Not all of the energy that is absorbed is used. Some of the absorbed energy is converted to heat. The efficiency level is about 10-20%.
How does the biosphere consist of interdependent and interrelated ecosystems?
Ecosystems have effects on other ecosystem and sometimes also depend on each other. For example, the substances produced in one ecosystem may travel to other ecosystems where they are used.
For example, the ice in the Antarctic contains lead from vehicle exhausts.
What is a pyramid of energy?
A pyramid of energy is a diagram showing how much energy flows through each trophic level in a community.
Why is a pyramid of energy shaped the way it is?
Less energy flows through each successive trophic level. Energy is lost at each level, and therefore less is passed on to the next level.
What is the role of saprotrophic bacteria and fungi (decomposers) in recycling nutrients?
They secrete digestive enzymes into dead organic matter (dead plants and animals and feces). The enzymes break down the organic matter and the nutrients within them are released. Saprotrophs absorb the substances that they need. Without saprotrophs, the nutrients would stay in the dead organic matter and other organisms would become deficient.
Why is energy lost between the different levels of energy pyramids?
1. Some organisms die before they are eaten by organisms in the next trophic level.
2. Some parts of organisms (bones, hair) are not eaten.
3. Some parts of organisms are indigestible and pass out as feces.
What units are used in the pyramids of energy?
Energy per unit area per unit time- kJ m^-2 year^-1
Do energy and nutrients leave ecosystems or are they recycled?
Energy is not recycled. It flows through food chains and then is lost as heat.
However, nutrients must be recycled. They are used again and again.
State an example of a food chain containing 3 links (4 organisms).
Passionflower (Passiflora schummaniana) --> Heliconius butterfly (Heliconius erato) --> Tegu lizard (Tupinambis teguixin) --> Jaguar (Panthera onca)
State an example of a food chain containing 3 links (4 organisms).
Carrot plant (Daucus carota) --> Carrot fly (Psila rosea) --> Flycatcher (Muscicapa striata) --> Sparrowhawk (accipiter nisus)