environmental mock Flashcards
population definition
a group of organisms of a single species occupying a particular area
community definition
all the populations of different organisms that live together in a habitat
habitat definition
the place where organisms live
Abiotic factors definition
The non living factors in a habitat and how they impact each other. Eg light intensity, temperature, soil pH
ecosystem definition
a community and the habitat in which it lives
biotic factors definition
The living factors in a habitat and how they impact each other. eg competition for environmental resources, grazing, predication, disease
Biodiversity definition
The diversity of plant and animal life in a particular habitat, affected directly by biotic and abiotic factors
Why is only about 10% energy transferred from one trophic level to the next?
Energy loss is mostly due to respiration in the form of thermal heat
Zonation definition
The gradual change in the distribution of species across a habitat. This can be caused by the gradual change in an abiotic factor eg light soil ph water depth
Describe the 4 stages in the carbon cycle
- Carbon enters the atmosphere as carbon dioxide from respiration and combustion.
- Carbon dioxide is absorbed by producers to make glucose in photosynthesis.
- Animals feed on the plant passing the carbon compounds along the food chain. Most of the carbon they consume is exhaled as carbon dioxide that was formed during aerobic respiration. The animals and plants eventually die.
- Decomposers break down the dead organisms and return the carbon in their bodies to the atmosphere as carbon dioxide by respiration. In some conditions, decomposition is blocked. The plant and animal material may then be available as fossil fuel in the future for combustion which releases CO2 into the atmosphere
Greenhouse gas definition and examples
A gas that contributes to the greenhouse effect by absorbing infrared radiation
eg: Water vapour, Carbon dioxide, Nitrous oxide, Methane, CFCs
When does fossilisation occur?
Fossilisation occurs when things do not fully decay when they die due to the conditions in the soil. Fossil fuels are then formed over millions of years via a process called locking in. These include coal, oil, natural gas and peat.
Bad human activities that contribute to greenhouse gases
Burning fossil fuels- releases CO2 into the atmosphere
Agriculture- agricultural practices lead to the rise of nitrogen oxides in the atmosphere
Deforestation- Trees absorb carbon dioxide during photosynthesis. If they are cut down, there will be higher amounts of CO2 in the atmosphere
Dumping waste in landfill- when the waste decomposes, it produces methane
How does the greenhouse effect work
Electromagnetic radiation at most wavelengths passes through the Earth’s atmosphere.
The Earth absorbs most of the radiation and warms up.
The Earth radiates energy as infrared radiation.
Some of the infrared radiation goes into space.
Some of the infrared radiation is absorbed by greenhouse gases in the atmosphere.
The lower atmosphere warms up.
