Ecosystems (6) Flashcards
What is a habitat?
The place where an organism lives
What is a population?
All the organisms of one species in a habitat
What is a decomposer?
An organism that breaks down dead or undigested organic material
What is a producer?
An organism that produces organic molecules using sunlight energy
What is a consumer?
An organism that eats other organisms
What is a trophic level?
A stage in a food chain occupited by a particular group of organisms
What is an ecosystem?
It is all the organisms living in a certain area and all the non living conditions found there. It is a dynamic system, which means that it is changing all the time.
What are biotic factors?
They are the living features of an ecosystem.
- predators
- prey
What are abiotic factors?
They are the nonliving features of an ecosystem
- temperature
- rainfall
- topology
- soil nutrient availability
- pH
- Salinity
How are rock pools affected by abiotic factors?
Rock pools are heavily influenced by the tides. At high tide they are completely submerged by the ocean so experience similar abiotic factors to the ocean ecosystem. However at low tide they experience more extreme abiotic conditions, only some organisms can tolerate these conditions.
How are rock pools affected by biotic factors?
Seaweed can be a food source for consumers such as limpets that graze on this produce. Intense competition for food can limit the number of organisms that are present in a small rock pool ecosystem.
How are playing fields affected by abiotic factors?
Rainfall and sunlight affect the growth of the producers in the ecosystem. In a very wet year, the soil may become waterlogged, making it difficult for plants to frow. Poor plant growth may decrease the number of consumers the ecosystem can support.
How are Playing fields affected by biotic factors?
Producers include grass and other plants such as daisies, clover, and dandelions. The large amount of these plants might attract a large number of organisms that use them as a food source.
How are large trees affected by biotic factors?
Insects such as caterpillars can use the leaves of a tree as a source of food. However, if they consume all the leaves on a tree, they can slow tree growth and even lead to its death.
How are large trees affected by abiotic factors?
Drought conditions can negatively impact the growth of a tree. In severe cases it can result in the whole tree dying.
How does energy enter an ecosystem?
The main route which energy enters an ecosystem is through photosynthesis. Plants convert light energy into a form that can be used by other organisms, they store it as biomass.
How is energy transferred throuh an ecosystem?
Energy is transferred though the living organims of an ecosystem when organisms eat other organisms.
What is biomass?
Biomass is the mass of living material.
What do food chains and food webs show?
They show how energy is transferred through an ecosysem.
What is the difference between a food chain and food webs?
Food chains show simple lines of energy transfer. Food webs show lots of food chains in an ecosystem and how they overlap.
How much of the energy is transferred between trophic levels?
around 10% of the total avaliable energy is transferred between trophic levels.
What is the gross productivity?
The rest of the available energy 40% is taken in.
What percentage of energy do organisms waste and how?
Around 60% is never taken in by the organisms
- plants don’t use all the light energy in photosynthesis
- some sunlight isn’t used as it hits part of the plant that cannot photosynthesise
- some parts of food are not eaten by organisms, so the energy isn’t taken in, they pass to the decomposers
- some parts of food are indigestible, so they pass through the organism and come out as waste.
How much is lost to the environment as respiratory loss?
30% of the total energy available is lost to the environment when organisms use energy produced from respiration for movement or body heat.