Topic 3.3 Biodiversity Flashcards
Species definition
A group of organisms that can reproduce with each other to produce fertile offspring.
Biodiversity definition
The measure of the variety of living organisms in a habitat and their genetic diversity.
Abiotic factors
-Air
-Temperature
-Minerals
-Salinity
-Light intensity
-Soil pH
-Water
-Humidity
-Turbidity
-Soil composition
Biotic factors
-Predation
-Food availability
-Competition
-Mutualism
-Parasitism
-Disease
Species richness
The number of different species in an area.
Species evenness
Relative numbers of different types of organisms (calculate the proportions of each species as a percentage of the total abundance).
Index of diversity
Species richness and abundance are both taken into account in a formula
The Simpson’s Diversity Index formula
d= diversity index
N= total number of organisms
n= total number of organisms of each species
Σ= sum of
What might cause e biodiversity measurements to vary across the world?
-Natural events (eg. floods)
-Climate change (eg. severe drought)
-Abiotic factors
-Human activities (eg. deforestation)
-Time of day sampled
-Areas with higher photosynthetic rate
-Time of year sampled
Endemic species
A species is classified as endemic to an area if it is found nowhere else in the world.
To be classified as a hotspot area it must have 1500 endemic species.
Genetic diversity
The total number of different alleles in the gene pool of a population.
The greater the number of different alleles within a population, the greater the genetic density of that species.
Gene pool
Refers to the combination of all genes (including alleles) present in a reproducing species.
A large gene pool has extensive genomic diversity and its better able to withstand environmental challenges.
Describe the link between genetic diversity and species survival
-Traits that make them resilient
-Drop in genetic diversity can lead to extinction
-Genetic bottleneck occurs when a population is greatly reduced in size
-The greater the genetic diversity, the more likely the species will be able to adapt to environmental change.
Ethical
-Denying future generations to use renewable recourses if biodiversity is destroyed
-Nature is a source of pleasure for some
-Human activities could cause mass extinction due to global climate change
-If biodiversity is lost when a species becomes extinct, unique combinations of DNA are lost.
Economic
-Ecosystems provide us with fibres for clothing
-Ecosystems help maintain air quality
-A healthy ecosystem is important for human health and wellbeing
Provisioning services
-Food
-Medicines
-Fuel
-Fibres for clothing