Key Area 3.1 - Ecosystems Flashcards
Define the term ecosystem
A natural biological unit made up of both living and non living parts
Identify abiotic parts of an ecosystem
- Sunlight and water
- Air and wind
- Rocks and soil
Identify biotic parts of an ecosystem
- Plants and algae
- Animals
- Micro-organisms such as bacteria and fungi
Identify the components that make up an ecosystem
Habitats
Populations
Communities
Describe the term population
All the members of one species that exist in an ecosystem
Identify the interactions of species with other species in the community
Competition and predation
Define the term producer
An organism that can make its own food by photosynthesis
Includes plant and algae
Define the term consumer
An organism that feeds on other organisms for energy
Define the term herbivore
An animal that feeds only on producers (plants and algae)
Define the term carnivore
An animal that feeds only on other animals
Define the term omnivore
An animal which feeds on both plants and other animals
Define the term predator
An animal that hunts other animals for food
Define the term prey
A type of animal that is hunted for food
Define the term food chain
A diagram that shows the feeding relationships of organisms living together in an ecosystem
At each level in a food chain 90% of energy is lost as:
Heat
Movement
Faeces
10% of the energy is used for growth
Give an example of a food chain
Antarctic food chain
Phytoplankton - shrimp - squid - weddell seal - killer whale
Describe what happens in a food chain
They start with producers (green plants) that change light energy to chemical energy (food) through photosynthesis
When an organisms eats another organism, energy is transferred
This transfer of energy can be represented as a food chain.
What do the arrows in a food chain indicate.
The direction of energy flow
Define the term species
A group of organisms that can interbreed to produce fertile offspring
Define the term biodiversity
The range of different species in an ecosystem
Identify human impacts on biodiversity
Air pollution
Water pollution
Deforestation
Overfishing
Define the term habitat
An area of an ecosystem where an organism lives
Eg. Riverbank, pond water, soil
Define the term community
All the different populations of organisms that live in a habitat
Includes: plants, animals and micro-organisms (such as bacteria and fungi)
Define the term food web
Food chains are linked together as food webs to show how energy flows from one organism to another
Describe what happens in a food web
Always start with producers
Herbivores feed on producers and are known as a primary consumer
Animals that feed on primary consumers are known as a secondary consumer
Animals found at the top of food chains are known as tertiary consumers or top predators
Define the term niche
The role that an organism plays in an ecosystem
What does the niche of an organism include?
The use it makes of the resources in an ecosystem (light, temperature and nutrient availability)
Also includes interactions with other organisms in the community through competition, parasitm and predation
Define why competition occurs
When resources are in short supply and organisms struggle for the same resources
Define the term interspecific competition
Competition which occurs between members of different species
Define the term intraspecific competition
Competition which occurs between members of the same species
This is more intense than interspecific competition
