Biodiversity Flashcards
When does one ecosystem start and one end?
Life on Earth is connected through the cycling of nutrients and the transformation of energy through food webs.
Ecosystems are generally homogeneous, but some regions within an ecosystem may vary.
Define biological species concept.
Created in 1942 by Ernest Mayr.
The individual members must be able to interbreed and produce viable, fertile offspring to be classified as a particular species.
Define habitat.
An area or environment where an individual or species lives within an ecosystem.
Comment on the variety of ecosystems in Australia?
Australian ecosystems vary widely and exhibit great diversity (e.g. forest, grassland, desert, coral reef, tropical savannah, tropical rainforest, temperate rainforest, etc.)
Issues with the morphological species concept.
Structures are most appropriate to compare when characterising a species.
Amount of variation must be seen in the structures before a new species is characterised.
Define environment?
The abiotic and biotic components of the ecosystem.
Define biotic.
The living components of an ecosystem.
Define abiotic.
The non-living components of an ecosystem.
Define parasitism.
Where one species benefits at the expense of the other.
Define ecosystem?
An interacting community of populations of organisms and the physical environment in which they live.
Rules for binomial system.
Genus (first letter uppercase) then species (first letter lowercase)
Must be either italicised or underlined
Define population.
A group of individuals belonging to the sam species living in a particular area at the same time
Define morphological species concept.
A species is characterised by their form or morphology (most commonly used for fossils)
Define cladogram.
A diagram constructed using cladistics that shows the evolutionary relationship between organisms
What does Bacteria include?
Microscopic single celled organisms.
Define phylogenic trees.
Phylogenetic trees are diagrams that show relationships between organisms based on shared common ancestors.
If the entire key has two choices at each branching point, the key is dichotomous.
Describe the biodiversity of Australia.
Landscape and the types of plants and animals, including marsupials.
1 million species of plants, animals and insects
What does Protista include?
Amoebae
What are the 7 kingdoms?
Animalia, Plantae, Protista (Eukarya)
Archaea (Archaea)
Bacteria (Bacteria)
Define Taxonomist.
A scientist who studies organisms and places them into taxa
Define keystone species.
A species of relatively low abundance in a higher trophic level that allows the coexistence of a number of lower trophic level organisms in a particular area
Prevents any one of the organisms in the lower trophic levels from monopolising food, resources and space.
Allows for richer biodiversity within a restricted area.
Define dichotomous keys.
Dichotomous keys are tools used to identify organisms which involve choosing between a series of two options until an organism is identified.
What are the three types of symbiosis.
Parasitism, mutualism, commensalism
What are the 3 domains?
Eukarya
Archaea
Bacteria
Notes on genetic biodiversity.
Every individual carries large number of genes
Code for all of their inherited traits
Different individuals carry many different genes
Populations with higher genetic diversity are more resilient and more likely to survive sudden changes in the environment
How do abiotic factors acting in an area affect the biodiversity of an area?
Harsh abiotic factors decrease a regions biodiversity.
Stable or healthy abiotic factors lead to a high biodiversity in a region.
What did the voyages of discovery in the 18th and 19th century provide?
Wealth of information about the biodiversity of Earth’s plants and animals.
Lead to the development of the concept of ecosystems.
Describe the distribution of species around the world?
Organisms are not uniformly distributed across the globe.
Occur as collections of interacting populations within specific physical environments