11.1 Biodiversity Flashcards
Define biodiversity
The variety of living organisms present in an area
Why is biodiversity important?
- Needed for a balanced ecosystem
- All species depend on one another
- Balanced ecosystems provide us with food, oxygen and other materials we need to survive
Where is biodiversity the strongest?
The closer a region is to the equator, the higher the biodiversity
What are the different levels of biodiversity?
- Habitat biodiversity
- Species biodiversity
- Genetic biodiversity
What is habitat biodiversity? How does it affect biodiversity?
Number of different habitats found within an area - each habitat can support many species
-The greater the habitat biodiversity, the greater the species biodiversity will be within that area
What habitat types are there in the UK? How does UK’s habitat biodiversity compare to other areas?
Meadows, woodlands, streams and sand dunes - so UK has a large habitat biodiversity
On the other hand, Antarctica is covered in ice so has a low habitat biodiversity as few species live here
How does natural countryside compare to ploughed countryside?
Natural - river, woodland, hedgerow, wild grassland - more species than ploughed fields making a single habitat
What are the two types of species biodiversity? Define them
Species richness - number of different species living in an area
Species evenness - comparison of the number of individuals of each species living in a community
(Community - all the populations of organisms in a particular habitat)
How can an area differ in species biodiversity?
An area can differ in species biodiversity even if there’s the same amount of species
E.G. a cornfield and grass meadow could both have 20 species. However, in the cornfield, 95% of the community is corn with the remaining 5% made up of other species. Species in the grass meadow will be more balanced in their populations.
Define genetic biodiversity?
The variety of genes that make up a species
What leads to genetic biodiversity?
Different versions of genes (alleles)
How can genetic biodiversity affect a species?
Genetic biodiversity can lead to different characteristics being shown
E.G. Some genes are the same for all dogs - these are genes that define the organism as a dog. Some genes have many alleles - they code for the wide variation of characteristics seen between different dog breeds, such as size or coat length
What is the benefit of genetic biodiversity?
Allows a species to better adapt to a changing environment and is more likely to result in individuals resistant to diseases
