Chapter 10 - Biodiversity Flashcards
what is classification
the organisation of living organisms into groups
what will all members of a species have in common
they are breed to produce fertile offspring
what is the name given to the current system of naming organisms
the binomial system
what did Linnaeus do
Devised a universal system of naming organisms
what languages are the names of organisms written in
greek or latin
what is the first name of an organism
the generic name of the genus
what is the second name of an organism
the specific name or the species
what are the three rules that apply when writing the names of organisms
1- must be underlined in handwritten
2- first letter of the genus should be a capital letter
3- if the species is unknown it can be written as sp
what is biodiversity
the variety of living organisms in an area
what is a habitat
the place where an organism lives
what is a community
all the populations of different species in a habitat
how can members of the same species identify each other
they resemble each other either biochemically or physically
what are the four main advantages of courtship
- members of the same species can recognise each other
- organisms identify a mate capable of freeing
- organisms form a pair bond
- synchronise mating
what must a prospective mate be
mature and fertiles
why is it important to ensure mating only occurs between members of the same species
so that fertile offspring are produced
why is it important to synchronise mating
to ensure the maximum probability of the sperm and egg meeting is achieved
what do males use courtship for
to determine if the female is receptive to mating because females only release eggs at certain times
what is taxonomy
the science of classification
what will organisms of the same species exhibit
similar courting behaviour
what is artificial classification
base on physical characteristics and their functions rather than evolutionary origins
what is phylogenetic classification
based upon the evolutionary relationships. it divides organisms into groups using shared features they have received from ancestors and arranges these groups into a hierarchy
what is a hierarchy
a group contained within a larger group but with no overlap
what does the first point on a phylogenetic tree show
a common ancestor of all family members
what do the branches on a phylogenetic tree show
A common ancestor from which different group diverged
how to tell if two species on a phylogenetic tree are closely related
they diverged away from each other recently
what is each group in taxonomy called
a taxon
what is phylogeny
the study of the evolutionary history of groups of organisms
what are the three domains
archaea, bacteria, and eukarya
characteristics of domain archaea
newly discovered cell types included 1 kingdom - the archaebacteria
how do archaea differ from bacteria
their genes and protein synthesis mechanisms are closer to that of eukaryotes
no murein in cell walls
a more complex form of RNA polymerase
characteristics of domain bacteria
1 kingdom - the eubacteria
what are eukarya
a group of organisms Made up of multiple eukaryotic cells
what are phyla
the largest groups in each kingdom
characteristics of eukarya
membrane bound organelles
no murein in cells walls
larger ribosomes than bacteria and archaea
membrane containing fatty acid chains attached to glycerol by ether linkages
characteristics of domain eukarya
4 kingdoms- protista, Animalia, plantae and fungi
what is species diversity
the number of individuals of each species in a community
what is ecosystem diversity
the range of different habitats
what is species richness
the number of different species in a particular area at a given time
what is local biodiversity
the variety of different species in a small habitat
what is global biodiversity
the variety of species on earth
what is ecosystem diversity
the range of different habitats within one particular area
what impact does agriculture have on biodiversity
natural ecosystems develop from complex communities.
agriculture ecosystems are controlled by humans.
farmers select the most productive crops.
the number of species and number of alleles they posses decreases.
for economic reasons the yield must be large
any one area can only support a certain amount of biomass
if most of an area is taken up by a crop there is little room for anything else
these organisms must outcompete the crop for nutrients, light and space which rarely occurs
direct practises which have reduced biodiversity 4
- removal of hedgerows
- creating monocultures
- filling ponds and draining marsh and other wetland overgrazing of land
why has the overgrazing of land reduced biodiversity
it prevents the regeneration of woodland
why have monocultures reduced biodiversity
fewer organisms can be supported
why has hedgerow and woodland removal reduced biodiversity
species lose habitats and food sources
ways in which food production has increased 4
genetic modification
use of pesticides and herbicides
changes in farm practices
technology
why do pesticides reduce biodiversity
not only does it kill the insect themselves, but it also remes a food source for the food chain
indirect practices which have reduced biodiversity 3
use of pesticides and inorganic fertilisers
the absence of crop rotation
escape of effluent from silage stores into water stores
how has the eu helped matin biodiversity
offering farmers grants to return to a natural meadow
3 examples of conservation schemes
legal protection for endangered species
creating protected areas which further restrict development
environmental stewardship scheme encourages farmers to conserve biodiversity
how are people trying to maintain biodiversity 5
- maintain and create hedgerows and ponds
- leave wet corners of fields
- reduce the use of pesticides and inorganic fertilisers
- use of nitrogen fixing crops to improve soil fertility rather than fertilisers
- create natural meadows and replant native trees
how can observable characteristics help to classify organisms
characteristics are influenced by the genes an organism has, so organisms with similar characterises have similar DNA
what are there limitations with using observable characteristics help us to classify organisms
lots of characteristics are either influenced by environmental factors or by a number go genes
how can comparing mRNA sequences help us to classify organisms
mrna is coded for by dna complementary base pairing so by comparing two strings of mrna we can also compare two sequences of dna
how can amino acids help us to classify organisms
a sequence of amino acids is coded for by mrna so also dna. this means that we can compare the amino acid sequence for the same protein in two species and count the number of similarities or different in order to see how similar they are
how can proteins be used to test the similarity between two organisms
if two proteins and therefore two organisms are similar they will bind to the same antibody, so you can’t eat to see how well two proteins bind to the same antibody
how can dna be used to test the similarity between two organisms
modern technology has allowed us to determine the entire base sequence of an organisms dna
we can compare the dna of members of one species to that of members of another species in order to see how similar they are.
closely related species will have a higher percentage of similarity in their da base order
when a species gives rise to another species through evolution how would we expect their dna to differ
initially it would be very similar
however, over time, mutations would develop and the nucleotide sequence in the new species would change over time
problems with dna sequencing to classify organisms
not all dna is functional and codes for proteins
what does a percentage similarity table show you
how similar two organisms are- if the two are very similar the percentage will be higher
how can you tell that two organisms are very similar by looking at their dna
the more similarities between the sequences the more similar the two are
how can antibodies and antigens be used to compare organisms
serum albumin from species a is injected into species b
series b produces antibodies complementary to the antigens in the albumin of species a
serum from species b is mixed with serum from species c
the antibodies in serum c reposed to their corresponding antigens in serum b
these antibodies form a precipitate
the more preicipate forms the close two species are relates
what is interspecific variation
when one species differs form another
what is intraspecific variation
when organisms in the same species differ form each other
what is variation
the differences that exist between individuals
what two factors is variation caused by
genetics and the environment
what are the two reasons that a sample might not be representative
sampling bias
chance
method of random sampling
1- divide the study area into a grid of numbered lines
2-use a random number generator to obtain a series of coordinates
3- take samples at the intersections of these coordinates
how to minimise the chances of our data not being representative
use a large sample size
analyse the data collected
why does using a larger sample size reduce the chances of our data not being representative
anomalies will have less influence over the result
the data is more reliable
what is skewed distribution
when it is shifted slightly to one side
how to calculate the mean
total of all values / number of values
what is the mode
the most common value
what is a normal distribution curve
a bell shaped curve that is symmetrical about the mean
what is the median
the middle value
why is the mean useful
you can easily compare one sample with another
why is the mean not very useful
it gives you no information about the range of the data values
what is standard deviation
how much the values in a single sample vary
how to find standard deviation from a graph
it is the point where the curve changes from being convex to concave
how much of the data lies between one standard deviation
68%
how much of the data lies between two standard deviations
95%
when there is no information on the number of significant figures to use what should you do
use the same number as the data given to you ni the question
how to draw error bars on a graph
they extended one standard devariton above and below the mean
