Eco-sysyem And Distribution Of Organisms Flashcards
What is the definition of ecosystem
A community of organisms living in a particular habitat and their interactions with each other and their shared environment.
What is the definition of community
Populations of different species living together in one area
Habitat
The place where an organism lives.
What is the definition of population
The tot number of individuals from the same species living in one area.
What is the definition of species
A group of organisms that can interbreed to produce fertile offspring.
What is the definition of a carnivore l
An organism that consumes only animal material
What is the definition of biodiversity
The total variety and abundance of different species present in an ecosystem
What is the definition of a producer
A (green plant) organism that makes their own food source through the process of photosynthesis.
What is the definition of a consumer
An organism that eats other organisms to obtain a food source.
What is the definition of a herbivore
An organism that consumes only plant material.
What is the definition of a omnivore
An organism that consumes both plant and animal material
What is the definition of a predator
An organism that hunts and kills other animals for food
What is the definition of prey
An animal that is hunted and killed by predators
What does a food chain show
The feeding relation ships between different organisms in an ecosystem and the direction of energy flow
What does a food web show
All feeding relationships that exist within an ecosystem
What does a stable ecosystem look like ?
A stable ecosystem has a wide variety of organisms living and interacting with each other, high levels of biodiversity.
(Loss of biodiversity can have a huge impact on the stability of an ecosystem)
What is the definition of a niche
The role that an organism plays
-the resources it requires to survive
-how it interacts with other organisms in the community.
What is the definition of competition
-Occurs when resources required for survival are available in short supply.
-One species is successful while others/the other is unsuccessful
What are the two types of competitor
Intraspecific and interspecific
What is intraspecific competition
Involves members of the same species, they compete for the exact same resource and has a higher level of intensity.
What is interspecific competition
Involves members of different species, compete for a few of the same recourses and has a lower level of intensity
What are 4 recourses that plants compete for to ensure their survival within an ecosystem
-water
-light
-soil space
-soil minerals
What are 4 resources that animals compete for to ensure their survival within an ecosystem
-water
-food
-territory
-Mates/the ladies
What does the term distribution mean
The spread of living organisms over an area affected by biotic and abiotic factors
What are biotic factors
Biotic factors are factors relating to the living component of an ecosystem which affect the distribution of organisms
What are five examples of biotic factors
-competition for recourses
-food availability
-predation
-disease
-grazing
What are abiotic factors
Abiotic factors are factors relating to the non-living components of an ecosystem which affects the distribution of organisms
What are four examples of abiotic factors
-temperature
-light intensity
-soil moisture
-pH
How do you measure the abiotic factor of light intensity?
Equipment Used is a light meter, possible source of error is shading the light meter, limitation of error is pointing the sensors directly at the light source
How do you measure soil moisture
Equipment used is a moisture meter, possible source of error is cross-contamination between samples and limitation of this error is cleaning the probe between readings
How do you measure temperature
Equipment used is a thermometer, possible source of error is inadequate time to read temperature and limitation of error is allowing the dial to settle before taking a reading.
How do you measure a soil pH
Equipment used is a ph Meter, possible source of error is cross-contamination between samples, limitation of error is cleaning the probe between readings.
What does the change in the size of population of one (or more) species affect
The survival chance of all other organisms within the ecosystem
What factors affect the levels of biodiversity
-biotic factors
-abiotic factors
-human activities
-natural hazards
What are six examples of human activities that affects the levels of biodiversity
-habitat destruction
-deforestation
-over fishing
-climate change
-intensive agriculture
-chemical and sewage spills
These actives influence changes in biotic/abiotic factors.
What are five examples of natural hazards which affect levels of biodiversity
-forest fires
-earthquakes
-tsunamis
-floods
-volcanic activity l
What is and what for is quadrat used for
A quadrat is a square frame with a known area
Used to estimate the number of plants or slow moving animals in a given area.
What are 3 errors and their limitations when using a quadrat
1)Using a small sample size - set up several quadrats to ensure the results are reliable, increase sample size
2) sample site may be specifically chosen-throw quadrants at random to ensure results are not biased.
3) counting organisms more than once-follow simple counting rules to ensure each organism is only counted once
What is a pitfall trap
-A pitfall trap is a cup placed level with the ground and covered with leaves.
-Used to estimate the number of small, active animals in a given area
What are three possible errors and limitations when using a pitfall trap
Using a small sample size-set up several pitfall traps to ensure reliable results
Trapped organisms may be eaten by predators - camouflage the pitfall traps using foliage
Trapped organisms may escape - check the contents regularly
What determines the type of organisms identified
The type of environment
What is ah indicator species
A species that by their presents/absence indicate levels of environmental quality.
They can indicate levels Of water pollution/air pollution.
What is a biological key used for
Biological keys are used to identify different organisms based on their physical appearance.
What is a transect line
Allows you to sample At regular intervals not random)
what factors affect levels of distribution within an ecosystem
biotic and abiotic factors
