ECOLOGY Flashcards
Ecology
Study of living organisms, their interactions with each other and the environment.
Ecosystem
A community of organisms and their environment
Biosphere
The part of the Earth and atmosphere inhabited by living organisms
Habitat
Place where an organism lives.
Niche
The role a species plays in the ecosystem.
Ecological Niche
The functional role played by an organism in the ecosystem.
Community
Populations of different species living and interacting with each other in the same habitat
Population
Group of individuals of the same species living in the same habitat.
Biotic factors are living or non-living?
Living
Examples of biotic factors?
Food - more rabbits = more foxes
Competition - between organisms for various resources e.g. red and grey squirrel
Predation - predators reduce the population of their prey.
Parasitism - Parasitic organisms reduce the health of their hosts causing many to die
Humans - Can bring positive or negative effects on the organisms.
Abiotic factors are living or non-living?
Non - living
Examples of abiotic factors
Edaphic
Climatic
Aquatic
What are edaphic factors?
Factors that effect soil condition
Altitude is a abiotic factor why?
Higher altitudes are colder and wetter and trees cannot live on very high altitudes.
What are climatic factors
Weather conditions over a long period of time.
Temperature is climatic factor why?
It affects the rate of reactions in living things.
Why is light intensity a climatic factor?
It affects the rate of photosynthesis
Name three more climatic factors
Day length
Humidity
Wind
Soil pH is an edaphic factor, why?
Plants and animals are adapted to specific pH values.
Why is water content an edaphic factor?
Plants need to absorb the water through their roots for functions like photosynthesis.
Name three other edaphic factors.
Air content
Mineral content
Soil type
How do aquatic habitats differ from terrestrial habitats?
They have different abiotic factors.
Currents are an aquatic factor why?
They move organism, plants and animals are washed away.
Wave action is an aquatic factor why?
Moves and damages organisms
Why is oxygen an aquatic factor?
In lower concentration
What is an autotroph/producer?
An organism which makes its own food e.g. photosynthesis and chemosynthesis
What is an consumer/heterotroph
An organism that obtains its food from another organism e.g. herbivores and carnivores.
What is a herbivore?
An animal which eats plants only!
What is a carnivore
An animal which eats meat only!
What is an omnivore?
An animal which eats both plants and meat e.g. crow
What is a decomposer?
It feeds on dead organic matter e.g. earthworm
What is a saprophyte?
bacteria and fungi that feed on dead organic matter e.g. Rhizopus
What is a primary consumer?
An animal which feeds on producers e.g. herbivores
What is a secondary consumer?
An animal that feeds on primary consumers. e.g. carnivores
What is a tertiary consumer?
Feeds on secondary consumers.
What is the primary source of energy?
The Sun
What happens in a food chain?
Energy flows from one organism to the next.
What is a food chain?
A sequence of organisms which shows the feeding relationships within a habitat.
E.g. of a food chain
(Producer)Rosebush -> (Primary consumer) Greenfly -> (Secondary Consumer) Ladybird -> (Tertiary Consumer) Hawk
What is a trophic level?
The feeding position of a species in the food chain.
What is a grazing food chain?
A sequence of organisms where each one is eaten by the next member in the chain.
What is a detritus food chain?
A food chain where the primary consumer feeds on dead organic matter e.g. dead leaves -> woodlouse -> blackbird.
What is a food web?
A web that consists of two or more interlinked food chains.
What is a pyramid of numbers?
A diagram showing the number of organisms at each stage in a food chain.
What is a limitation of the pyramid of numbers?
Can’t represent large numbers correctly.
What other pyramid of numbers can there be?
Inverted pyramid of numbers.
They are usually shown if a parasite is involved.
What are the two biological similarities between the nitrogen cycle and the carbon cycle?
Death and decay
Excretion
Describe the role of plants in the nitrogen cycle and carbon cycle.
Absorb nitrates and absorb CO2.
Describe the role of animals in the nitrogen cycle and carbon cycle.
They respire and consume plants.
Why is it important that nutrients are recycled in nature?
To be used time and time again.
During the nitrogen cycle, nitrogen from the air is converted to nitrates. Of what benefit is this?
So it can be used by living things.
Nitrates are formed directly from other molecules in the soil. Name one of these molecules.
Nitrifying bacteria.
Mention one role of animals, other than consumers, in the nitrogen cycle.
Decomposers feed off of their remains.
Name the family of plants which have a symbiotic relationship with nitrogen-fixing bacteria.
Fungi
The nitrogen in the air is converted to nitrates but the percentage of nitrogen in the air does not change. What process is responsible for this?
Nitrogen-fixing
What is the role of modern fertilizers in the nitrogen cycle?
Provide soluble nitrates.
Why do organisms need nitrogen?
To produce proteins.
