Ecology flash cards

The cards, front and back

1. 1
   Front

   Ecosystem

   Back

   All the living organisms in an area together with the non-living parts of their environment, interacting with each other.

2. 2
   Front

   Habitat

   Back

   The place where an organism lives.

3. 3
   Front

   Population and community

   Back

   A population is all the organisms of one species in a habitat. A community is all the populations of different species living in the same habitat.

4. 4
   Front

   Biotic and abiotic factors

   Back

   Biotic factors are living parts of the environment, such as predators, food and disease. Abiotic factors are non-living, such as light, temperature, water, soil pH and wind.

5. 5
   Front

   What is a producer?

   Back

   An organism that makes its own food, usually by photosynthesis, such as a plant or alga. Producers start almost every food chain.

6. 6
   Front

   Primary, secondary and tertiary consumers

   Back

   A primary consumer eats producers (a herbivore). A secondary consumer eats primary consumers. A tertiary consumer eats secondary consumers.

7. 7
   Front

   What do decomposers do?

   Back

   Decomposers, such as many bacteria and fungi, break down dead organisms and waste, returning nutrients such as nitrates to the soil.

8. 8
   Front

   What do the arrows in a food chain show?

   Back

   The direction of energy (and biomass) transfer, from the organism being eaten to the organism that eats it.

9. 9
   Front

   What is a food web?

   Back

   A set of linked food chains showing all the feeding relationships in an ecosystem. It shows that most animals eat, and are eaten by, more than one species.

10. 10
    Front

    What is a trophic level?

    Back

    A feeding level in a food chain. Producers are at level 1, primary consumers at level 2, and so on.

11. 11
    Front

    Why are food chains rarely longer than four or five links?

    Back

    Only a small part of the energy at one trophic level is passed to the next, commonly taught as roughly 10%. The rest is lost through respiration, movement, heat and waste, so there is not enough left to support many more levels.

12. 12
    Front

    What does a pyramid of biomass show?

    Back

    The mass of living material at each trophic level. It is almost always widest at the bottom, with producers.

13. 13
    Front

    Name the main processes in the carbon cycle.

    Back

    Photosynthesis removes carbon dioxide from the air. Respiration, decomposition and combustion return it. Feeding passes carbon compounds along food chains.

14. 14
    Front

    Name the main processes in the water cycle.

    Back

    Evaporation and transpiration put water vapour into the air, condensation forms clouds, precipitation brings it back down, and water runs off or soaks into the ground to rivers and seas.

15. 15
    Front

    Predator and prey populations

    Back

    When prey numbers rise, predators have more food so their numbers rise too, a little later. More predators then eat more prey, so prey numbers fall, followed by predator numbers. The populations rise and fall in cycles.

16. 16
    Front

    What is competition in ecology?

    Back

    When organisms need the same limited resource. Animals compete for food, mates and territory. Plants compete for light, space, water and mineral ions.

17. 17
    Front

    What is an adaptation?

    Back

    A feature that helps an organism survive and reproduce in its environment. It can be structural (body shape), behavioural (migration) or functional (how body processes work).

18. 18
    Front

    Mutualism and parasitism

    Back

    In mutualism both species benefit, like bees and the flowers they pollinate. In parasitism one species (the parasite) benefits and the host is harmed, like a tapeworm in an animal.

19. 19
    Front

    What is biodiversity and why does it matter?

    Back

    The variety of all the different species in an area or on Earth. High biodiversity makes ecosystems more stable because species depend on each other for food, shelter and other needs.

20. 20
    Front

    How do you use a quadrat?

    Back

    Place a square frame at random positions in an area and count the organisms inside it each time. Find the mean per quadrat, then scale up to estimate the population of the whole area.

21. 21
    Front

    What is a transect used for?

    Back

    A line across a habitat, with quadrats placed along it, used to see how the distribution of organisms changes from one place to another, such as from a shady to a sunny area.