B4 Flashcards
What is an ecosystem?
All the living organisms and physical conditions in an area
What is a community?
The organisms within the ecosystem
What is a habitat?
Where the community of an ecosystem live
What is the population?
The total number of organisms of each species
What are the 3 groups of organisms in a community?
Producers
Consumers
Decomposers
What are producers?
Organisms that make their own food by photosynthesis- all plants and algae
What are consumers?
Organisms that cannot make their own food - they have to eat other organisms for energy - all animals
What are decomposers?
A speak o group of consumers that get energy by feeding on dead or decaying material
What is the biomass?
The mass of living material present
What is a trophic level?
Each step in the food chain
What is a food web?
Multiple food chains linked together
What 2 factors affect an ecosystem?
Biotic factors
Abiotic factors
What is a biotic factor?
Living factors such as trees, squirrel and hedgehogs - the number of these organisms also counts
What is an abiotic factor?
Non-living factors such as rainfall and temperature and oxygen availability
In terms of factors, what is competition?
The most common biotic factor
How does light intensity affect communities?
Light needed for photosynthesis so lower light intensity causes leaves to be larger
How does temperature affect communities?
It affect the enzymes that control metabolic reactions - plants and cold-blooded animals develop more rapidly in warmer temperatures as their metabolism will be better (warm blooded animals are not affected as much)
How does moisture level affect communities?
Lack of water usually means death for most organisms as water is a main component of blood plasma - lack of water causes plants to wilt.
How does lack of water affect plants?
They wilt because water is needed for to keep their cells turgid, which keeps plants upright - also needed for photosynthesis
How does soil pH affect communities?
Some plants grow better in acidic soil (ferns and rhododendrons)
Some plants grow better in alkaline soil (cucumbers and cauliflower)
What is competition?
Plants and animals need a number of different materials from their surroundings - they have to compete for these resources
What do plants need to survive?
Light
Water
Breeding partners
Space (territory)
Shelter
What do animals need to survive?
Food
Water
Breeding partners
Space (territory)
Shelter
What is interdependence?
How different organisms depend on each other within a community
What are ecological relationships?
The interactions between organisms
What are the 3 types of ecological relationships?
Predation
Mutualism
Parasitism
What is predation?
The name of the relationship between predator and prey - the size of the both populations directly affect each other
What is mutualism?
A mutualistic relationship between two organisms when both of the get benefits from the relationship
What is an example mutualism?
Oxpeckers that live on buffaloes - eat ticks and fleas on the buffalo’s skin - they get food while the buffalo gets free of irritation and potential disease
What is parasitism?
When only one organism in the relationship gains but the host suffers.
What is a parasite?
The organisms that get the benefits of a parasitic relationship
What is the host?
The organism that suffers in a parasitic relationship
What are examples of parasitism?
Mosquitoes and humans
Tapeworms in an animal’s digestive system
What is a pyramid of biomass?
The flow of biomass in a community