Ecology And Environment Flashcards
Define population
All the organisms of one species in a habitat
Define community
All the different species in a habitat
Ecosystem
All the organisms living in a particular area and all the non living conditions. Eg temperature, climate soil type
How could you estimate a population size in a habitat using a quadrat
A quadrat is a square frame enclosing a known area eg 1m2
1) place a 1m2 quadrat on the ground at a random point within the area you’re investigating
2) count all the organisms within the quadrat
3) multiple the number of organisms by the total area of the habitat. You can then do this again in another area and compare the population sizes
What’s a producer
Food chains always start with a producer e.g a plant. Producers make their own food using energy from the sun
What is a primary consumer
Producers are eaten by primary consumers, who are then eaten by secondary consumers
Give an example of a decomposer
All these organisms eventually die and get eaten by decomposer a e.g bacteria
What is the source of all energy in a food chin
Energy from the sun
Approximately how much energy is passed on to the next trophic level
10%
Give two reasons why energy is lost in food chains
Energy is lost to the surroundings as heat
Describe the water cycle
1) heat from the sun makes water evaporate from the land and sea, turning it into water vapour. Water vapour also evaporates from plants this is known as transpiration
2) warm water vapour is carried upwards (as warm air rises). When it gets higher up if cools and condenses to form clouds
3) water falls from clouds as precipitation as it is returned to the land and sea
State the six stages/key points of the carbon cycle
1) there’s only arrow going down. The whole thing is powered by photosynthesis. Green plants use the carbon from co2 in the air to make carbohydrates, fats and proteins
2) eating passes the carbon compounds in the plant along to animals in a food chain or web.
3) both plant and animal respiration while organisms are alive release co2 back into the air
4) plants and animals eventually die and decompose, or are killed and turned into useful products.
5) when plants and animals decompose they’re broken down by bacteria and fungi. These decomposer release co2 back into the air by reputation,as they break down the material
6) some usufel plant and animal producers e.g wood and fossil fuels are burned(combustion) releasing co2 back into the air
How does carbon enter the carbon cycle from air
Green plants use carbon from co2
Give two ways that carbon can enter the air from dead plants and animals
When plants and animals decompose they’re broken down by bacteria and fungi these decomposer a release co2 back into the air by respiration
Define habitat
The place where an organism lives eg a rocky shore or field