B7-Ecology AQA set Flashcards
What is classification?
The science of grouping organisms into taxons where those with similar characteristics are grouped together
Who suggested the five kingdoms?
Carl Linneaus
What are the five kingdoms?
- Animals
- Plants
- Fungi
- Protists
- Bacteria
Name the classification system in order:
Domain Kingdom Phylum Class Order Family Genus Species
What is a species?
A group of similar organisms that can successfully breed together and produce living fertile offspring
How are species identified?
By a Binomial Name
Who introduced the three domains?
Carl Woese
What enabled Carl Woese to introduce the three domains?
The improving methods of testing and viewing organisms with microscopes and the consequent changing of classifications
What are the three domains?
- Eukarya
- Prokarya
- Archaea
What does the Eukarya domain contain?
Organisms with cells that contain a nucleus
What does the Prokarya domain contain?
Organisms that lack a nucleus
What does the archaea domain contain?
Primative bacteria found living in extreme environments
Why have classification systems changes over times?
Due to the improvements in biochemistry and microscopy
What information do scientists use to draw phylogenetic trees?
Classification information- observable features, biochemicals (e.g. DNA)
Fossil records
What is the alternative name for the phylogenetic tree?
Evolutionary tree
Compare the major features of organisms from the plant and animal kingdom
- Animals can move their whole bodies from place to place whereas plants cannot move their whole bodies about
- cells of plants have a cellulose cell wall however the cells of animals do not have a cell wall
- plants can carry out photsynthesis to produce food whereas animals have to eat food
What do the community of organisms within an ecosystem do?
Interact with each other in a variety of ways
What is an ecosystem?
It’s the interaction of all organisms and non-living organisms , within a community including both biotic and abiotic
What is a community?
All the different populations of different organisms in an ecosystem with their own habitats
What are biotic factors?
Living
What are abiotic factors?
Mon-living
Give required examples of biotic factors:
- New pathogens
- Competition
- Predation
- Food supply
- Parasitism
Give required examples of abiotic factors:
- Wind intensity
- Soil pH
- Light intensity
- Mineral content
- Oxygen levels (aquatic animals)
- Moisture levels
- Wind direction
- Temperature
- CO2 levels (plants)
What do biotic and abiotic factors affect?
The population sizes of organisms
What does each organism rely upon others for in a community?
- food
- habitat/shelter
- pollination
- seed dispersal
What is a stable ecosystem?
Where there is a balance in population sizes due to interdependence
What do plants compete with eachother for within a community or habitat?
- light
- mineral ions
- water
- space
What do animals compete with eachother for within a community or habitat?
- territory
- food
- mates
What is the theory behind natural selection?
The most successful competitors are those that are best adapted , so will survive, breed and pass these adaptations onto the next generation
What is an adaptation?
A feature of a living organism that enables it to survive in its natural habitat. Often they provide a selective advantage
What are extremophiles?
Organisms (commonly bacteria and archaea) that are adapted to extreme hostile environments
What are some examples of extrme hostile environments?
- High temperatures
- High salt levels
- High pressure
What are the three types of adaptations?
- Structural
- Behavioural
- Functional (biochemical)
How are larger animals adapted to colder environments
They have a smaller surface area to volume ratio so they lose less heat energy
Where does energy in ecosystems originally come from?
The Sun
How is energy transferred in an ecosystem?
From plants to animals and then animals to animals before being lost to the environment
What does a food chain represent?
The flow of energy
How is energy lost at each trophic level?
Loss through respiration (e.g. heat)
Production of faeces and urine
What is the largest typical length of a food chain? Why?
5 organisms because so much biomass/energy is lost from the food chain at each stage, through uneaten material, waste products, faeces, energy for movement and keeping warm
What is the most energy efficient diet? Why?
Vegetarian as the most energy is consumed since it is direct from a producer
Whats the relationship between the number of predators and prey?
If the number of predators increases, inevitably the number of prey falls and vice versa. In nature, this occurs in regular cycles
What are the properties of a producer?
- Largest mass
- First trophic level
- Most energy
- Photsynthetic
What are the properties of a primary consumer?
- Herbivore
- Second trophic level
- Prey
What are the properties of a secondary consumer?
- Prey
- Predator
- Third trophic level
- Carnivore