Chapter 14 (Ecosystems) Flashcards
What is ecosystem and what are the components of ecosystems?
ecosystem - living + non-living
It includes:
- Producers
- Consumers
- Decomposers
- The physical environment
What are living and non-living components of an ecosystem called?
- living components - biotic components
- non-living components - abiotic components
What is habitat?
Habitat is the place where an organism lives.
What is population?
Number of the organisms of a particular species found in an ecosystem at a certain time.
What is community?
The populations of all species found in an ecosystem at a particular time.
How do ecologist count number of organism in a ecosystem?
By sample.
How are sampling done?
It can be done using a quadrat.
What does the size of quadrats depend on?
It depends on the size of the organisms being sampled.
What is needed to be consider when sampling an area?
It must be carried out at random to avoid bias.
How can sampling be done to avoid biased?
By using random number generator.
What is ecosystem’s biodiversity?
The amount of variation shown by species in an ecosystem.
What are the measurements of biodiversity?
- Species richness (number of different species present)
- Their evenness of number
What is the benefit of ecosystems with high biodiversity?
They are often more stable than ones with lower biodiversity.
Why higher biodiversity are more stable than ones with low biodiversity?
Because an ecosystem that is dominated by one or a few species is more likely to be affected by any sort of ecological disaster.
What are the interactions in ecosystem?
- Feeding among the organisms
- Competition among the organisms
- Interaction between organisms and the environment
What does food chain show?
It shows the feeding relationships between organisms within a ecosystem.
Food chain
_____ —–> _____ —–> _____ —–> _____.
Producer, Primary consumer, Secondary consumer, Tertiary consumer
What is more than one food chain called?
Food Web
Which kind of animals are primary consumers and secondary consumer?
Primary consumers - herbivore
Secondary consumers - Carnivore
How much energy from the eaten animal is transferred to the animal which eat it?
Only 10%
What is the name of animals that eat tertiary consumer?
Quaternary consumer
What do different stages in a food chain called?
Trophic levels
What does arrow mean in food chain?
Eaten by
What is the disadvantage of food chain?
They don’t give any information about how many, or what mass of organisms is involved and they don’t show the role of decomposers.
Biotic factors are _____?
Biological
Abiotic factors are ______?
Physical or chemical
What is ecosystem?
Ecosystem is a distinct, self-supporting system of organisms interacting with each other and with a physical environment.
What are examples of biotic factors?
- Food supply / competition for food
- Predation
- Parasitism
- Disease
- Presence of pollinating insects
- Availability of nest sites
What are examples of abiotic factors?
- Climate (light intensity, temperature)
- Hours of daylight
- Soil condition
- Pollution
- other factors specific to a particular habitat
What is main biotic factors affecting animals?
Food supply
What is main abiotic factor affecting large ecosystem?
Climate (Temperature/ rainfall)
What are factors affecting the species richness and their evenness depend on?
Type of ecosystem
What are ecological pyramids?
They are diagrams that represent the relative amounts of organisms at each trophic level in a food chain.
What are 2 main types of ecological pyramids?
- Pyramids of numbers
- Pyramids of biomass
What does pyramids of number show?
It represent the numbers of organisms in each trophic level in a food chain.
What does pyramids of biomass show?
It show the total mass of the organism in each trophic level.
Which ecological pyramid tend to always stay in pyramid shape?
Pyramid of biomass
What the mass of the of organism decrease in in pyramid of biomass?
- Some parts are not eaten
- Some pats are not digested and absorbed
- Some materials form excretory products
- Many materials are use to respire to release energy
These losses are repeated at each stage in the food chain.
What is a way of transferring energy between organisms?
Feeding
Why some marine food chains have six trophic levels?
Because of the huge amount of light energy reaching the surface water.
Which organisms pay key role in recycling and why?
Microorganisms since they break down organic molecules in the dead bodies of animals and plants into simpler substances.
What are some important process in cycling carbon through ecosystem?
- Photosynthesis
- Feeding and assimilation
- Respiration
- Fossilization
- Combustion
What fixes carbon atoms from carbon dioxide into organic compounds?
Photosynthesis
What does feeding and assimilation do?
It pass carbon atoms along food chains.
What release carbon dioxide into the atmosphere in carbon cycling?
- Respiration of animals, plants and decomposers
- Combustion of fossil fuels,
What is fossilization?
Where some dead organisms do not decay fully and become fossil fuels due to conditions in the soil.
Where are nitrogen included?
Proteins, vitamins, DNA and ATP.
What pass the nitrogen atoms along food chains?
Feeding and assimilation
What are importance process in cycling nitrogen through ecosystem?
- Feeding and assimilation
- Decomposition
- Nitrification
- Absorption of nitrogen by plant roots
What is nitrification?
Where nitrifying bacteria oxidized ammonia to nitrite and then to nitrate.
What does denitrifying bacteria do?
It use nitrates as energy source and convert them into nitrogen gas.
What reduce the amount of nitrate in the soil?
Denitrification
What convert nitrogen gas into ammonia?
Free-living nitrogen-fixing bacteria in soil
What is mutualism?
Where both organisms benefit from the relationship.
What converts nitrogen gas in the air into oxides of nitrogen (nitrite)?
Lightening
How does nitrogen from dead matter returns?
They return to soil as ammonia by decomposers.
Which kind of biomass is used to measure?
Dry biomass
