4.1.2 BIODIVERSITY Flashcards
Polymorphic genes
A gene that has more than one
allele
Captive breeding
Breeding endangered species in
zoos and other facilities to build a
healthy population of the animals
Reduces genetic diversity
Physiological
adaptation
Changes in the processes within an
organism
Antigenic
variability
When pathogenic DNA mutates
causing a change in shape of
antigen
previous immunity is no longer
effective as memory cells don’t
recognise new shape of antigen.
specific antibody no longer binds to
new antigen
Epidemic
When a disease spreads rapidly on
a national level
Pandemic
When a disease spreads rapidly on
a global level
Antibiotic
resistance
When a bacterium is no longer
killed by a particular antibiotic as it
has developed resistance to it.
This is often caused by a mutation
in the bacterium or receiving a copy
of an antibiotic resistance gene
from another bacteria - horizontal
transfer.
Personalised
medicines
This is known as pharmacogenetics
By analysing your DNA, it can be
possible to identify drugs that
individuals will respond better to
Synthetic biology
Using bacteria as medicine factories
It can also be used to research
chemical pathways and mechanisms
so that tissue engineering and
replacement may be possible and
regeneration of medicines.
Includes examples such as the
genetic engineering of bacteria to
make human insulin
Habitat
The range of physical, biological
and environmental factors in which
a species can live
Environment
The abiotic (non-living) factors in
an area
Gene pool
All the allleles in a population at a particular time
Genetic diversity
The number of different alleles in a
population
Gene flow
Sharing of alleles from one
population to another
Habitat diversity
A measure of the range of habitats
Species diversity
The number of different species
within an area and their abundance
to indicate biodiversity
This involves both species richness
and species evenness
Species richness
A measure of the number of
different species in a community
Specie evenness
The relative abundance of each
different species within a
community
Community
A measure of species diversity
An index of diversity combines both
the number of different species and
the population size of each within a community
D = diversity
N = the total number of organisms of ALL species
n = total number of organism of a particular species
Random sampling
Avoids bias and makes sure that all
individuals are equally as likely to be
included in any sample
Method for random quadrat sampling…
Two tape measures at right angles
to each other
Random number generator to
generate two numbers to serve as
coordinates on the grid
Place your quadrat at the
coordinates and record the data
Representative
sample
Large sample
Randomly sampled
Non-random
sampling
Opportunistic
Systematic
Stratified
Stratified
Populations or habitats can be
separated into groups to sample
from
Random samples are taken from
within each group (or strata)
Opportunistic
Sampling organisms which are
conveniently available
Involves bias
Unlikely to result in a sample that
accurately represents the
population
Systematic
Identifying different areas within a
habitat to sample
Often involves a belt transect
Used when there is a change in the
distribution of species within the
habitat and you want to investigate
the impact of the change on
biodiversity
Recording species
present in a quadrat
Density
Frequency
Percentage cover
Sampling
techniques for
animals
Sweeping nets
Pitfall traps
Pooters
Impact of
Agriculture on
Biodiversity
Clearing land for agriculture results
in the destruction of habitats
Chemical pesticides or fertilisers
disrupt habitats
Reducing the number of habitats
and food sources decreases
biodiversity
Reasons to
maintain
biodiversity
Ecological reasons- removing
natural habitats leads to food chain
disruptions
Economic reasons- deficient soil
can reduce the ability to grow crops
and make a profit, ecotourism
Aesthetic reasons- being around
nature and animals enriches
people’s life
Conservation
methods
In situ- within the natural habitat
Ex situ- not within the natural
habitat
Biodiversity
A measure of the range of habitats
From a small local habitat to the
entire Earth
A measure of species diversity
A measure of genetic diversity
Farming
techniques that
reduce biodiversity
Destruction of hedgerows
Selective breeding
Monocultures
Over-grazing
Filling in ponds and draining
wetlands
