topic 4C Flashcards
biodiversity
biodiversity
a measure of the variety of living organisms and their genetic differences.
genetic diversity
measure of how many variations there are in the genetic code between individuals of a particular species, or between different species.
species diversity
measures of how many different species are present in an area, and how many individuals of these species there are
habitat diversity
measure of how many different species there are in an area.
ecosystems
biological communities where organisms interact with one another and with their physical environment
species richness
he number of different species in an area
relative species abundance
he relative numbers of species in an area
biodiversity hotspot
an area with a particularly high level of biodiversity
allele frequency
the frequency with which a particular allele appears
within a population
endemic
a species that evolves in geographical isolation and is found in only one place
diversity index
a way of measuring the biodiversity of a habitat
genetic diversity
a measure of the level of difference in the genetic
make-up of a population
heterozygosity index
heterozygosity index a useful measure of genetic diversity within a
population expressed as:
number of heterozygous
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number of individuals in the population
ecology
the study of the relationships of organisms to one another
and to their physical environment
anatomical
adaptations adaptations involving the form and
structure of an organism
niche
the role of an organism within the habitat in which it lives
physiological adaptations
adaptations involving the way the body of the organism works, including differences in biochemical pathways or enzymes
behavioural adaptations
adaptations involving programmed or
instinctive behaviour making organisms better adapted for survival
population
a breeding group of individuals of the same species occupying a particular habitat and a
particular niche
gene pool
the sum total of all the genes in a population at a given time
selection pressure
the effect of one or more environmental factors that determine whether an organism will be more or less successful at surviving and reproducing; selection pressure drives speciation
Hardy-Weinberg equilibrium
the mathematical relationship between the frequencies of alleles and
genotypes in a population; the equation used to describe this relationship can be used to work out the
stable allele frequencies within a population
gene flow
gene flow the migration of either whole organisms or genetic material into or out of a population and into
another population, tending to make different populations more alike, but changing the allele frequencies within each individual population all the time
speciation
the formation of a new species
adaptive radiation
a process by which one species develops rapidly
resulting in several different species which fill different ecological niches
allopatric speciation
speciation that occurs when populations
are physically or geographically separated and there can be no
interbreeding or gene flow between the populations
hybridisations
the production of offspring as a result of sexual
reproduction between individuals from two
different species
marsupials
mammals that give birth to very immature young and
then protect them in pouches
monotremes primitive
mammals that lay eggs and feed their offspring with milk from mammary glands
placental mammals
mammals that provide for the developing fetus
during gestation through a placenta
sympatric speciation
speciation that occurs between populations
of a species in the same place; they become reproductively separate
by mechanical, behavioural or seasonal mechanisms; gene flow continues between the populations to some extent as speciation occurs
population bottleneck
the effect of an event or series of events
that dramatically reduces the size of a population and causes a
severe decrease in the gene pool of the population, resulting in large
changes in allele frequencies and a reduction in genetic diversity
founder effect
the loss of genetic variation that occurs when a small
number of individuals become isolated, forming a new population
with allele frequencies not representative of the original population
conservation
maintaining and protecting a living and changing environment
ex-situ conservation
the conservation of components of biological diversity (living organisms) outside
their natural habitats
in-situ conservation
the conservation of ecosystems and natural habitats, and the maintenance and
recovery of viable populations of species in their natural surroundings
captive breeding
programmes programmes where individuals of an endangered species are bred in zoos
and parks in an attempt to save the species from extinction, and if possible to reintroduce them to their
natural wild environment
Why are nitrates ions needed in a plant? What happens if deprived of it?
they are needed to make amino acids and therefore make proteins, also makes DNA and hormones. if there’s a lack of nitrates older leaves turn yellowing die, also stunt growth.
why are magnesium ion needed in a plant, what happens if deprived from it.
needed to produce the green pigment (chlorophyll), used to trap light for photosynthesis, also its needed to activate some plant enzymes. if there’s lack if plant can’t make enough chlorophyll it willl eventually die, also yellow areas start to develop, on older leaves and growth is slowed.
why are calcium ion needed in a plant, what happens if deprived from it.
in the middle lamella it will combine pectin to make calcium pectate, which holds cells together, also important in the permeability of membranes. If they lack, the plants stop growing points die and younger leaves are yellow and crinkly.
