U3 T1 Describing Biodiversity Flashcards
(39 cards)
biodiversity
the full range of different living things in a particular area or region; it can be described at various levels, including the range of different species, genetic diversity or the diversity of ecosystems present in a large area
ecosystem
a self-sustaining unit consisting of the interactions between the species in a community and the environment
species
the lowest taxon in Linnaean classification; it is always italicised and combined with genus
biotic factors
living components in an ecosystem e.g animals, plants and bacteria
abiotic factors
non-living components in an ecosystem e.g landscape, minerals and weather conditions
species richness
the no. of species present in an ecosystem
s= no. of species/sqrt(total no. of individuals)
relative species abundance
the no. of individuals present for each species in an ecosystem
% = (no. of individuals in a species/ no. of individuals for all species) x 100
percentage cover
the percentage of the quadrat that a species takes up
percentage frequency
percentage of quadrats in which a species appears
Simpsons diversity index (D =1−( ∑n(n-1)/N(N-1))
what does n and N mean?
n = no. of individuals of each species
N = totals no. of individuals at the site
abiotic limiting factors
light, temperature and chemical environment
biotic limiting factors
food, predators, diseases/parasites, competition for resources
limiting factor
is an aspect of the environment that restricts an organisms ability to live there, they can be biotic or abiotic and limit abundance and distribution
factors that affect photosynthesis
light intensity, CO2 concentration, temperature
biological classification
is a hierarchical system and based on methods or reproduction similarity of physical features
describe the Linnaean system (based on physical features)
- based on similarities of obvious physical traits
- hierarchy of taxa (Life, Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species)
- uses binomial nomenclature (using the Genus and Species)
r-selection
- very high mortality rate
- produce a large no. of offspring
- smaller body sizes
- low investments of energy in terms of care and nurture
- unstable environment
- reach maturity in early life
K-selection
- very low mortality rate
- produce a small no. of offspring
- bigger body sizes
- high investment of energy in terms of care and nurture
- stable environment
- longer life expectancy
molecular phylogeny
classification using DNA sequences and proteins to demonstrate evolutionary relationships.
5 reproductive methods
sexual or asexual
internal or external fertilisation
placental or marsupial mammal
egg laying
produce milk to feed their young
clade
a group comprising all of the descendants of a particular organism
common assumptions of cladistics
common ancestry
bifurcation
physical change
bifurcation
when a lineage splits it splits into two groups
molecular rate
estimated no. of base pair changes per nucleotide per generation of a population