Ecology And The Environment Flashcards
Community definition
A community is a group of populations of different species living together in the same place (e.g. A woodland community could contains squirrels, deer, insects, birds e.t.c) different species in a community rely on each other
Habitat definition
A habitat is a place where an organism lives, referring to a general area where many species are found. (It is a physical place)
Ecosystem definition
An ecosystem describes all the species, populations, habitats and communities in an area. It is a self contained, interacting community of organisms and the environment. (Lake ecosystem, woodland ecosystem)
What is the first thing in a food chain
A producer e.g. A plant.
What comes after the producers in a good chain
Primary, secondary, tertiary consumers
What categories do these consumers fall in to
Herbivores, carnivores and omnivores
What are detritivores?
Animals that feed off of waste (maggots, worms, dung beetles e.t.c)
What is biomass?
The mass of material in living organisms
What happens to energy as it passes through a food chain?
It gets used up and less is available at each trophic level
Why is there only about 10% of energy transferred from one trophic level to another
Because energy is passed out of the food chain by being used as heat energy, for life processes (e.g. movement) and faeces and remains are passed to decomposers. Less energy is transferred at each level of the food chain so as a result the biomass gets smaller.
Why is not all the biomass from a plant transferred to animal biomass?
Because cows do not eat all of the plant
Some of the plant biomass eaten is excreted by the animal and not turned into animal biomass
Some of the plant biomass eaten is used as energy for metabolic reactions such as respiration or producing heat so is not converted to animal biomass
Not all the plant biomass eaten can be digested (cellulose)
Water cycle
Ground water goes into rivers and streams which makes wet surfaces and bodies of water. This water then evaporates giving water vapour in the air. The water vapour then undergoes condensation to make cloud which turns into ground water again by precipitation. The ground water is turned into water vapour in the air also by being taken up by plants and then transpiration occurs giving water vapour in the air.
Carbon cycle
CO2 in the air is turned into organic material in plants by photosynthesis. This organic material in plants turns into fossil fuels, organic material in animals and dead organic waste(also produced by the organic material in animals. The organic material in plants and animals also puts CO2 back into the air by respiration. Fossil fuels puts CO2 back into the air by combustion. The dead organic waste of plants and animals is turned into organic materials in decomposers by decomposition, the decomposers then put CO2 back into the air by respiration.
What are the three ways that nitrogen in the air is converted into plant proteins.
Nitrogen in the air is turned into nitrates taken up by plants via:
- nitrogen fixing bacteria (in soil and root nodules of legumes)
- electrical storms
- haber process (nitrogen in air converted to ammonia in fertilisers which is turned into nitrates via nitrifying bacteria)
How can excreta and dead protein materials from both animals and plants be turned back into nitrates for plants or back into nitrogen in the air?
Excreta and dead animal proteins is decomposed by decomposers which produces ammonia.
The ammonia is turned into nitrites by nitrifying bacteria and then into nitrates by nitrifying bacteria which is then taken up by plants. OR
The ammonia is turned into nitrogen in the air by denitrifying bacteria.
