Ecosystems Flashcards
All 13 cards in this deck
What is the difference between the biotic and abiotic components of an ecosystem?
Biotic = the living parts (e.g. plants, animals, bacteria); abiotic = the non-living parts (e.g. water, soil, light, temperature).
What is the role of producers in an ecosystem?
They make their own food by photosynthesis, converting the sun's energy into food for consumers.
What is the role of decomposers in an ecosystem?
They break down dead plant and animal material, returning nutrients to the soil.
In a UK freshwater pond ecosystem, name one producer and one consumer.
Producer: pond weed (or algae). Consumer: tadpole (or heron).
What is the difference between a food chain and a food web?
A food chain is one straight line from producer to consumer; a food web is a number of connected food chains, showing that most organisms eat and are eaten by more than one species.
Which way do the arrows point in a food chain or food web?
e.g. grass → rabbit → fox
In the direction of energy flow, from the organism eaten to the organism that eats it — so the arrow points from grass to rabbit, and from rabbit to fox.
What are the steps of nutrient cycling in an ecosystem?
e.g. a UK woodland
- Plants take up nutrients from the soil to grow — trees grow leaves.
- Dead material falls to the ground — leaf litter builds up in autumn.
- Decomposers break it down, returning nutrients to the soil to be taken up again.
What are the steps to work out the effect on a food web of removing one species?
e.g. disease kills most of the trout in a pond
- What did it eat? Those species increase — more aquatic insects and crayfish.
- What ate it? Those species have less food and decrease — herons have fewer fish.
- Follow the knock-on effects further through the web — more insects eat more water plants.
True or false? If one species in an ecosystem dies out, only the animals that ate it are affected.
False. Components of an ecosystem are interdependent, so changing one part has knock-on effects through the whole system, including the plants and the soil.
True or false? Tropical rainforests are found in a band around the Equator.
True. They lie roughly between the Tropics of Cancer and Capricorn, where it is hot and wet all year.
What pattern do large scale global ecosystems show on a world map?
They occur in broad bands running roughly east–west, parallel to lines of latitude, because climate changes with latitude.
Which global ecosystem has trees that drop their leaves in winter, and where is it found?
Temperate deciduous forest, found in mid-latitudes such as western Europe and eastern North America.
Give two characteristics of tropical grassland (savanna).
Distinct wet and dry seasons, and tall grasses with scattered drought-resistant trees; the largest area is in Africa.