B4.1 - Ecosystems Flashcards
What is an ecosystem?
All of the biotic and abiotic factors in a habitat
What is an environment?
All of the conditions that surround an organism
What is a habitat?
The area where an organism lives
What is a population?
The total number of organisms for a species
What is a community?
The population of all the species in a habitat
What are decomposers?
Organisms that break down food outside their bodies using enzymes and absorb the nutrients
Such as bacteria and fungi
What are detritivores?
Organisms that feed on decaying matter
What do plants need to survive?
Light
Water
Carbon dioxide
Minerals
Space
What do animals need to survive?
Food
Water
Breeding partners
Shelter
Space
How can biomass be lost?
Cellular respiration
Energy used for movement, growth
Urine
Faeces
What is egestion?
Indigestible parts of an organism that pass straight through the body
How does carbon cycle?
Living organisms, fossil fuels, atmosphere
Trapped in oceans and rocks
What happens to the nitrogen compounds in dead organisms?
They are broken down and released into the soil as ammonia
How do plants benefit from nitrogen-fixing bacteria?
They live on the roots and combine with nitrogen from the air to form nitrates which are used by the plant
The bacteria obtain carbon from the plant and a secure environment in nodules
How is carbon released into the atmosphere?
Respiration
Decomposition
Burning fossil fuels
Why do atmospheric CO2 levels vary through the day?
Photosynthesis only happens during light, so it is removed more during the day
Respiration is carried out constantly, so it is released at a relatively consistent rate
