B4 Flashcards
What is an ecosystem
All the organisms and living conditions present in an area
What are all the organisms living within an ecosystem called
A community
What is a habitat
The place an organism lives (emg a pond)
What is a population
The total number of organisms in a species that live in a specific area
What is a producer
Organisms that make their own food through photosynthesis
What is a consumer
Organisms that cannot make their own food and must eat other organisms to gain energy
ALL ANIMALS ARE CONSUMERS
What are decomposers
A special group of consumers
They gain their energy by feeling on dead or decaying material
What is an autotroph
An organism which generates its own energy
What is a photoautotroph
An organism that uses simple inorganic molecules to synthesise complex organic molecules
How do photoautotrophs increase their biomass
Photoautotrophs absorb energy from the sun in photosynthesis and create glucose.
This is then turned into carbohydrates, fats and proteins, which are then used as energy stores for growth and repair
As an organism grows its biomass increases - the mass of living material
What is biomass
The total living mass of organisms in an area
How is energy transferred between organisms
Consumers eat producers, which pass on lipids, proteins, carbohydrates and glucose
This energy is stored and transferred in the production of atp.
This organism then grows and its biomass increases
What is a food chain
A chain that displays what an organism eats
The arrows show the biomass transfer from one organism to the next
What is a trophic level
Each step in a food chain
E.g a producer would be trophic level one
What is a food web
A complex ‘web’ of food chains that are interlinked.
These are needed as not only one animal is eaten by another. Usually it would have multiple predators
What are the main factors in an ecosystem
Biotic - living factors (E.g the plants and animals)
Abiotic - non-living (physical) factors (E.g the rainfall, temperature or wind speeds in an ecosystem)
How do biotic factors effect communities
Organisms may compete with each other for food and space
Competition is the main biotic factor
How does light intensity (abiotic factor) affect communities
Light intensity is needed for photosynthesis
The greater the accessibility of light the greater the success of a plant
Plants evolve to grow successfully - in areas of low light intensity plants have larger leaves
How does temperature (abiotic factor) affect communities
Temperatures greatest effect is on the enzymes which control metabolic reactions
In warmer climates plants develop more rapidly as their metabolisms are faster.
This also affects cold blooded animals like lizards who need the sun to warm them up
How do moisture levels (abiotic factor) affect communities
For most plant and animal species, a lack of water leads to death
(Emg water is the main component in blood plasma)
Water is needed to maintain turgor pressure in plants and for photosynthesis
How does soil pH (abiotic factor) affect communities
The pH of a soil affects the minerals it contains.
Some plants grow better in acidic soil such as ferns
Some plants grow better in alkaline soils such as cucumbers
What do plants need to survive
Light
Water
Carbon dioxide
Minerals
Space
What do animals need to survive
Food
Water
Breeding partners
Space (territory)
Shelter
What is competition
When two or more organisms are contesting for a resource