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143 Cards in this Set
- Front
- Back
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Define: Species
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A group of individual organisms very similar in appearance, anatomy, physiology, biochemistry and genetics.
Able to interbreed and produce fertile offspring |
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Define: Habitat
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The place where individuals in a species live.
Specific locality with a specific set of conditions |
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Define: Biodiversity
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The variety of life, range of living organisms to be found.
(Includes all the different plant, animal, fungi, and micro-organism species worldwide) |
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At what three levels can biodiversity be considered
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Habituation
Species specific Genetically |
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How can biodiversity be considered at the habituation level?
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Range of habitats in which different species live
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How can biodiversity be considered at a species specific level?
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The differences between species, functional differences and structural differences.
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How can biodiversity be considered at the genetic level?
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Genetic variation between individuals belonging to the same species?
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Why can we not be sure of the number of different species on earth?
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We cannot be sure we have found all the species
New species are being found all the time Evolution and speciation are continuing Many species are becoming extinct or are endangered |
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Define: Random sampling
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The study of a small random part of a habitat and then assuming it contains a representative set of species that can be applied to the whole habitat.
This will be done multiple times |
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How can you randomise your sample area?
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-Take samples at regular distances across a habitat
-Use random numbers generated by computer to plot co-ordinates within a habitat -Select co-ordinates from a map of the area and use a portable GPS system to find exact position inside habitat |
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What two methods can be used to sample plants?
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Quadrats
Transects |
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Define: Abundance
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Frequency of occurrence
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How can quadrats be used in random sampling?
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Place the quadrat at random in the habitat.
Measure abundance |
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How can abundance be measured using quadrats?
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ACFOR scale
Percentage cover using gridded quadrat Percentage cover using point frame |
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What is the ACFOR scale?
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A - Abundant
C - Common F - Frequent O - Obvious R - Rare Apply a letter to each species |
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How would you use a point frame to measure abundance?
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Lower frame into quadrat and record any plant touching the needle.
If frame has 10 needles and is used 10 times, 100 results will be recorded. So each plant recorded will have 1% cover |
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What is a transect and how can it be used to measure abundance?
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Line taken across the habitat in which samples are taken along it.
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How might a transect be used in a large habitat?
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A line transect would be use, plants touching the line recorded at set intervals.
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What is an interrupted belt transect?
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Using a quadrat at set intervals along a transect
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What is a continuous belt transect?
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Place a quadrate beside the line and move it along the line continuously providing quantitative data.
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Why is sampling so important in measuring the biodiversity of a habitat?
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To measure biodiversity, need to observe all species present, identify and count individuals.
This is not practical and so small portion of habitat is studied carefully and a sample. |
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What is the problem of sampling animals?
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They move and if presence is detected may hide away.
Therefore you must trap in order to estimate. |
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What five methods can be used to trap animals?
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Sweep netting
Collecting from trees Pitfall trap Tullfren funnel Light trap |
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Explain the method of sweep netting
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Walking through habitat with stout net, sweeping in wide arcs catching small animals.
Pooter can be used to collect animals before they fly away |
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Explain the method of collecting from trees
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Spread white sheet under tree and knock branch with stout stick.
Vibration dislodges small animals |
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Explain the method of the pitfall trap
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Small container buried in soil.
Animals fall into container Trap contain some water of paper to stop animals crawling back out. Sheltered from rain so it doesn't fill up |
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Explain the method of Tullgren funnel
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Place leaf litter in funnel
Light above drives animals downwards as litter dries out and warms up Animals fall through mesh screen to be collected in jar underneath funnel |
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Explain the method of using a light trap
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UV light to attract insects with a vessel of alcohols underneath, moths and insects eventually fall in to liquid.
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Why must we sample?
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Study how our activities affect our environment, and produce environmental impact assessment (EIA)
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Define: Species richness
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Number of species present in a habitat
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How can species richness be measured?
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Qualitative survey to estimate.
Make observations with the habitat and record all species seen. |
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Define: Species evenness
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The number of individuals in a species found in a habitat
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How can species evenness be measured?
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Quantitative surveys:
Surveying frequency of plants or Measure the density of animals in a habitat |
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How can you survey the frequency of plants in a habitat?
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Use random sampling techniques then count the number of plants of each species per unit area or measure percentage cover.
Large plants -> Count number of individuals Small plants -> Percentage cover |
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How can use measure the density of animals in a habitat?
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Large animals -> count individually
Smaller animals -> capture using sampling methods and use mark-and-recapture technique. |
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What is the mark and recapture technique?
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-Capture a sample of animals and mark in a way that causes no harm.
-This will be C1 -Capture a second sample, new animals label C2 and recaptured animals C3 total population = (C1 * C2)/C3 |
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What is n in Simpson's diversity?
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Number of individuals of a particular species (or % cover for plants)
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What is N in Simpson's diversity?
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Total number of all individuals of all species (% cover for plants)
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What does a high value in Simpson's diversity show?
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A diverse habitat.
A place of many different species and organisms. Small change will probably not have a huge effect. |
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What does a low value in Simpson's diversity show?
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Habitat dominated by few species.
A small change to environment could damage or destroy the whole habitat |
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Define: Natural Classification
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The process of sorting living things into group by grouping things according to how closely related they are.
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Define: Taxonomy
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The study of the principles of classification
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Define: Phylogeny
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The study of evolutionary relationships between organisms
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How is phylogeny used in classification?
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Allows placement into evolutionary trees, and therefore the ability to see how closely two species are related and also how recently they shared a common ancestor in the past -> this is used as a basis for natural classification
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What are the eight taxa of classification?
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Domain
Kingdom Phylum Class Order Family Genus Species |
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How do different are individuals at higher ranks of the taxa?
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Can be very great
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What happens as you go down the taxa?
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Diversity between individuals decreases and it becomes increasingly difficult to separate closely related species.
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Define: Binomial system
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Uses two names to identify each species:
The Genus The Species name |
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Why do we use the binomial system?
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Common name does not work well because
-Same organism may have different name in different parts of one country -Overuse of one name in different countries |
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What two answers are usually found in a dichotomous key?
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Yes and no
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What makes a good dichotomous key?
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One fewer questions than the number of species it has to identify
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What three groups did Aristotle divide animals into?
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Lives and moves in water
Lives and moves on land Moves through the air |
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What was the main basis of early classification?
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Anatomy and appearance
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What did the original animal kingdom include that has now bee taken out?
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Single celled organisms that had animal like features
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How is biochemistry now used in classification?
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Cytochrome c
DNA |
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What is cytochrome c used in?
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Process of respiration
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How can cytochrome c be used in classification?
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All living organisms except chemosynthetic prokaryotes have cytochrome c.
Not identical in all species. Amino acids in CC can be identified If sequences just slightly different -> closely related If sequence is very different -> species are not so closely related |
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How can DNA be used to classify species?
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Comparison of DNA sequences, the more similar the sequence, the more closely related they are.
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What are the three domains?
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Archaebacteria
Eubacteria Eukaryotae |
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Where did the two domains, Eubacteria and Archaebacteria, originate?
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The prokaryotae kingdom
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What makes a good dichotomous key?
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One fewer questions than the number of species it has to identify
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What three groups did Aristotle divide animals into?
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Lives and moves in water
Lives and moves on land Moves through the air |
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What was the main basis of early classification?
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Anatomy and appearance
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What did the original animal kingdom include that has now bee taken out?
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Single celled organisms that had animal like features
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How is biochemistry now used in classification?
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Cytochrome c
DNA |
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What is cytochrome c used in?
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Process of respiration
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How can cytochrome c be used in classification?
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All living organisms except chemosynthetic prokaryotes have cytochrome c.
Not identical in all species. Amino acids in CC can be identified If sequences just slightly different -> closely related If sequence is very different -> species are not so closely related |
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How can DNA be used to classify species?
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Comparison of DNA sequences, the more similar the sequence, the more closely related they are.
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What are the three domains?
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Archaebacteria
Eubacteria Eukaryotae |
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Where did the two domains, Eubacteria and Archaebacteria, originate?
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The prokaryotae kingdom
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What are the differences between the domain Eubacteria and the two domains Archaebacteria and Eukaryotae?
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Structural differences:
Different cell membrane structure Flagella with different internal structure Different enzymes for RNA building No proteins bound to their genetic material Different mechanisms for DNA replication and building RNA |
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What are the similarities between the two domains Archaebacteria and Eukaryotae?
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Similar enzymes for building RNA (RNA polymerase)
Similar mechanisms for DNA replication and building RNA Production of some proteins that bind to their DNA |
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Outline the characteristic features of Prokaryotes
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No nucleus
Loop of 'naked' DNA not arranged in linear chromosomes No membrane bound organelles Smaller ribosomes than others Respire on mesosomes Cells smaller than those of eukaryotes Free-living of parasitic |
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Outline the characteristic features of Protoctists
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Eukaryotes
Mostly single-celled Mostly free-living Some photosynthesis, some ingest prey, some feed using extracellular enzymes some are parasites Do not qualify to belong to any other kingdom |
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Outline the characteristic features of Fungi
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Eukaryotes
Have a mycelium consisting of hyphae Walls made of chitin Cytoplasm is multi nucleate Cause decay of organic matter |
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Outline the characteristic features of Plants
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Eukaryotes
Multicellular Cells surrounded by cellulose wall Autotrophic nutrition Produce multicellular embyos from fertilised eggs |
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Outline the characteristic features of Animals
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Eukaryotes
Multicellular Heterotrophic nutrition Usually able to move Fertilised eggs develop into ball of cells -> blastula |
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Define: Variation
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Presence of variety of differences between species
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What can variation be found?
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Anywhere, even within a species
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What three types of variation are there?
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Genetic variation
Continuous variation Discontinuous variation |
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What kind of variation can be found within a species?
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Eye, hair and skin colour
Nose, chin ear shape etc |
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Define: Genetic variation
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Caused by differences between the genes and the combination of genes or alleles
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Define: Continuous variation
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Variation in which there is a full range of intermediate phenotypes between two extremes
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Define: Discontinuous variation
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There are discrete groups of phenotypes with no or very few individuals in between
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Define: Phenotype
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Any observable characteristic or trait of an organism
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What are three examples of continuous variation?
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Height in humans
Length of leaves on an oak tree Length of stalk of toadstool |
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What are three examples of discontinuous variation?
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Sex
Flagella or no flagella (bacteria) Human blood groups |
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What are the genetic causes of variation?
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The combination of alleles we inherit are not the same as that in another living thing (except identical twins)
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What are the environmental causes of variation?
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Amount and type of food we eat
Amount of exposure to sunlight Conditions of environment i.e windy, branches grow away from win etc |
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How are environmental and genetic variations interlinked?
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Changes in environment affect genes that are active, bringing about visual changes
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Define: Adaption
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Feature/variation that enhances survival and long term reproductive success.
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How can adaptations help organisms cope with environmental stresses?
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-Help find enough food or photosynthesise well
-Find enough water -Gather enough nutrients -Defend itself from disease and predators -Survival physical conditions of environment i.e change temp -Respond to changes in environment -Still have enough energy to reproduce successfully |
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What are the three types adaptations which enhance survival?
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Behavioural
Physiological/biochemical Anatomical |
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How do behavioural adaptations help enhance survival?
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A behaviour adaptation is an aspect of the behaviour of an organism that helps it to survive the conditions it lives
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How do physiological/biochemical adaptations help enhance survival?
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Ensures the correct functioning of cell processes.
I.e producing the correct enzymes to respire sugar present in environment (yeast) |
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How do anatomical adaptations help enhance survival?
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Any structure that enhances the survival of the organism is an adaptation.
I.e flagella on bacteria |
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What were Darwin's four observations of natural selection?
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Offspring generally appear the same as their parents
No two individuals are identical Organisms have the ability to produce large numbers of offspring Populations in nature tend to remain fairly stable in size. |
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Define: Natural selection
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'Selection' by the environment of particular individuals that show certain variations which will help the individual survive and pass on the variation to the next generation
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What were the consequences of the four observations listed by Darwin?
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Managed to propose a mechanism for the process of evolution.
Made it easier to believe in the theory of evolution. |
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Define: Speciation
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Formation of new species
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How long does speciation take?
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Long slow accumulation of changes
Except in bacteria which can pass through several generations in a few hours |
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How does speciation occur?
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If changes occur in part of a group but cannot spread to the whole group, these differences will eventually build up until differences are so great they cannot interbreed.
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What are reproductive barriers?
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Any factor that prevents effective reproduction between members of a species
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What are the two types of speciation?
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Allopatric
Sympatric |
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What is allopatric speciation?
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Geographical seperation between individuals of a species
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What is sympatric speciation?
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A change in species which causes individuals to be unable to breed properly.
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What evidence is available that supports the theory of evolution?
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Fossils
Biological molecules Protein variation DNA |
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How can fossils be used to support the theory of evolution?
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Fossils show the slight changes occurring over time:
Modern horse (55million years) Evolution of humans (3-4 million years) |
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Why is fossil evidence not completely reliable?
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Incomplete
Only hard parts of organism fossilised Fossils can be damaged of destroyed |
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How can biological molecules be used to support the theory of evolution?
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-One species gives rise to another, both likely to have same biological molecules.
-Two closely related species will have evolved recently from the same ancestor, likely to have identical/very similar biological molecules |
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How can DNA support the theory of evolution?
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Genes can be compared by sequencing the bases in DNA.
The more similar the DNA patter, the more closely related. |
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How does evolution work?
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-Variation occurs
-Variations giving advantages selected -Individuals with advantage survive and reproduce -Characteristics inherited -Next generation becomes better adapted. |
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How has resistance to insecticides in pests developed?
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Insects may be able to break down the insecticide using enzymes -> insecticides metabolised
Target receptor protein on the cell membrane may be modified |
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What are the impacts of insects becoming resistant to pesticides?
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-Insects take in the chemicals eaten by predator who receives large dose and pesticides eventually eaten by humans
-Unable to control the spread of outbreaks such as malaria. |
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How has resistance to drugs in microorganisms developed?
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Antibiotics taken, most bacteria killed but some survive.
People feel better and stop taking, allows surviving bacteria to survive and reproduce to create resistant strain |
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What are the impacts of microorganisms becoming resistant to antibiotics?
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"Evolutionary arms race" Medical researchers struggling to develop new and effective drugs before bacteria can become resistant.
Multiple resistant bacteria. Multiple antibiotics prescribed |
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What are the reasons for conservation of animal and plant species in terms of the economy?
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1997 economics attempted to quantify economic value:
$33 x 10^12 |
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What are the reasons for conservation of animal and plant species in terms of ecology?
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Ecosystem performs valuable processes for humans
-Regulation of atmosphere and climate -Purification and retention of water -Formation and fertilisation of soil -Recycling nutrients -Detoxification and recycling waste -Crop pollination (for food) -Growth of timber, food and fuel |
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What are the reasons for conservation of animal and plant species in terms of ethical grounds?
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All living organisms have the right to survive and live in the way they are adapted to.
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What are the reasons for conservation of animal and plant species in terms of aesthetic reasons?
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Feeling of joy and well being when observing variations of nature
Studies show recovery in injured/stressed more rapid when exposed to pleasing natural environmental conditions. |
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What are the consequences of biodiversity due to climate change in terms of agriculture?
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-Higher carbon dioxide levels, altering photosynthesis
-Higher temp -> inc. growth rate -Longer growing seasons -More evaporation of water, more precipitation. -Change in distribution of precipitation -Loss of land, rise in sea levels -Increased salinity of soil -Selectively bred crops no longer suited to conditions |
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Explain the agricultural benefits of maintaining biodiversity
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Decline in biodiversity = genetic diversity declines
Organisms evolved over thousands of years adapted to overcome problems of environment -> use to breed new crop varieties to cope with climate change. New medicines to be found in plants. Vaccines developed from microorganisms |
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What are the consequences of biodiversity due to climate change in terms of disease?
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-Crops in new areas encounter new diseases and pests, not adapted to resist.
-Longer growing season, more time for pests in increase in number -More species of pests and disease may be able to overwinter successfully causing greater infestations earlier in year -Tropical diseases may become problem in Europe. |
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Define: Conservation in situ
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Minimise human impact on natural environment and protecting natural environment
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What are the advantages of conservation in situ?
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-Permanently protects biodiversity
-Facilitates scientific research -Possible to restore ecological integrity of area -Secures environmental future |
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What are the disadvantages of conservation in situ?
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Difficult to persuade some countries that legislation is needed
Difficult to enforce legislation. Tourists feeding protected animals or leaving litter Protected animals coming out of reserve |
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Define: Conservation ex situ
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Conserving endangered species by activities take place out of normal environment
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What are the advantages of conservation ex situ in animal species?
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Concentrate on breeding endangered species.
Protected from predators Health can be maintained Can use modern techniques to preserve large amounts of genetic material |
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What are the disadvantages of conservation ex situ in terms of animals?
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-Not kept in natural environment
-Many fail to breed successfully -Space is limited, restricts genetic diversity -Leads to lack of variation -Animals have to survive reintroduction |
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What are the advantages of conservation ex situ in terms of plants?
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-Stored in huge numbers in a small space
-Often bred asexually -Produced in large numbers so little disturbance to ecosystem |
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What are the disadvantages of conservation ex situ in terms of plants?
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-Any collection causes some disturbance
-May not hold representation of genetic diversity -Asexual reproduction limits variation |
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What is a seed bank?
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Collection of seed samples that remain viable for decades.
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What use do seed banks have?
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Benefits include food and building materials for local communities
Disease resistant crops Habitat reclamation and repopulation |
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How are seeds preserved?
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Decrease moisture
Decrease temperature |
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How are tests for viability of seeds carried out?
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-Plant seeds in petri dishes
-Monitor conditions of seeds -Measure germination rate and success of germination |
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What is CITES?
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Convention of International Trade in Endangered Species of Wild Fauna and Flora.
International agreement to ensure international trade in specimens of wildlife does not threaten their survival. |
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What are the aims of CITES?
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Regulate and monitor international trade in selected species of plants and animals.
Ensure that international trade does not endanger survival of populations in the wild Ensure that trade in artificially propagated plants is allowed, subject to permit Ensure that some slightly less endangered wild species may be traded subject to permit as agreed between the exporting and importing countries |
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What us the CBD?
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Rio Convention on Biodiversity
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What are the aims of the CBD?
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Conservation of biological diversity.
Sustainable use of its components Appropriate shared access to genetic resources Appropriate sharing and transfer of scientific knowledge and technologies Fair and equitable sharing of benefits arising out of the use of genetic resources |
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Define: Environmental Impact Assessment
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Procedure to assess the likely significant effects that a proposed development may have on the environment
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What are the reasons for carrying out an EIA?
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Avoid or minimise any significant adverse affects on the biological diversity of an area
Ensure that any potential environmental consequences of a development are taken into account Promote the exchange of information, consultation and notification of any development that might affect another partner state. Promote arrangements for emergency response to activities or events that present a grave and imminent danger to biological diversity |
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What are the three criteria assessed in an EIA?
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Size of development
Environmental sensitivity of location Types of impact expected |
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What are the three stages of procedure for an EIA?
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Developer compiles an environmental statement including assessment of local biodiversity and effect development may have
Environmental statement publicised Authority takes it into account when making a planning decision |
