Biodiversity Flashcards
Define habitat
Place where a community of organisms normally lives
Define community
All populations of different organisms interacting at a particular place at the same time
Define ecosystem
All living and non-living components in an area
Define biodiversity
Number and variety of organisms in an area
Range and variety of genes, species and habitats in a particular area
Define species diversity
Number of different species and number of individuals of each species in a community
Define genetic diversity
Different genes possessed by individuals of the same species
Define ecosystem diversity
Number a different hábitats in an area
What types of diversity sre there
Species
Genetic
Ecosystem
Bio
What do individuals of the Same species have in common
Both occupy same ecological niche
Breed to produce fertile offspring
They are similar
What is the system of naming organisms called
Binomial system
Describe the binomial system
Given generic name (genus) and specific name (species)
How do you name an organism if you don’t know its species but do know its genus
Name genus and then add sp.
Why is the binomial system used
Prevent confusion and allows a universal language to be used
How do similar courtship behaviours indicate two organisms are genetically similar
Courtship behaviours are determined by genes and show similar biochemical and physical processes
How does courtship behaviour allow for successful mating?
Allows recognition and identification of organism of same species
Allows bond pair to form (raise offspring)
Indicates sexual maturity and fitness
Allows synchronisation of mating (egg and sperm more likely to meet)
Define classification
Grouping of organisms
Why is classification important
Allows clarity and better communication
Define taxonomy
Theory and practise of classification
What are the two types of classification
Artificial and phylogenetic
Describe artificial classification
Based on physical, convinient features.
Features of same function but different evolutionary origins (analogous characteristics)
Describe phylogenetic classification
Using evolutionary relationships
Using homologous features determined by genes passed on by ancestors (same evolutionary origin despite function)
Uses hierarchy
Name the taxonomic ranks (taxa)
Domain Kingdom Phylum Class Order Family Genus Species
Name the domains in phylogenetic classification
Archea
Bacteria
Eukarya
Describe the bacterial domain
70s ribosomes No histones No membrane bound organelles Murein cell walls Circular DNA Unicellular
Describe the archea domain
70s ribosomes
Genes and protein Synthesis more similar to eukaryota
No Murein in cell walls
More complex RNA polymerase compared to bacteria
Ether links in lipids
Unicellular prokaryotes
Describe the eukaryotic domain
No Murein in cell wall if present Histones bound to DNA Membrane bound organelles 80s ribosomes Ester links in lipids Multicellular
Define phylogeny
Classification of organisms based on evolutionary relationships
How is phylogeny usually depicted
Using a phylogenetic tree
What evidence is used in a phylogenetic tree
Fossil records DNA Homologous structures Karyotype Anatomy
Define Karyotype
Shape and number of chromosomes
What are the two ways of measuring diversity
Species richness and diversity index
What is used to calculate the diversity of a community using no of species and individuals
Simpson diversity index
Why is the diversity index better than species richness
Takes into account how many individuals there are of each species
Takes into account dominant species
Provides quantitative data
What does a diversity index of 1 indicate
No diversity
Compare the biodiversity of a harsh and a less harsh environment
Harsh= low biodiversity, less stable and dominated by climatic factors
Less harsh= high biodiversity, stable and dominated by organisms
What is meant by dominated by climatic factors
Climate has a greater effect on the ecosystem than organisms do
What are the two types of ecosystem. Give characteristics
Natural= high BD mad complex
Agricultural = one main crop and low BD
Describe an agricultural ecosystem
Pesticides are used which reduces presence of species able to outcompete the crop
Plants compete for resources such as mineral ions and water
Reduced gene pool as all have desired characteristics (profitable)
What is a monoculture
When all crops grown are of Same variety
How has food production been increased
Use of pesticides and fertilisers
Increased use of biotechnology
Better farming practises
Monoculture
Larger farms
How is biodiversity reduced
Use of pesticides Removal of hedgerows Monoculture Filling in ponds Overgrazing No intercropping or crop rotation with nitrogen fixing crops Escape of silage
What methods of conservation are there
A shaped hedgerows Cut verges after flowering Don't drain fields Intercropping instead of herbicides Crop rotation with nitrogen fixing crops Use organic fertilisers Plant trees in areas of low BD Create ponds Use GM instead of pesticides Create natural meadows and use Hay not grass for silage Produce conservation headlands
Why are hedgerows so important
Prevent soil erosion Provide wide break Provide shelter from predators Diverse habitat Shade and food
Why are rains forests so diverse
Large range of plant species = more variety of food and more habitats
Why does deforestation occur
Acid rain Cattle Houses Road making Crops Oil and mining
What are the consequences of deforestation
Soil erosion
Land slides
Low BD
Global warming
Why should we conserve the rainforest
May contain medicine we haven’t discovered
Regulate climate
How is diversity observed within a species
Differences in observable characteristics
What causes diversity within a species
Genetic variation and environmental influences
Why are observable differences in a specific characteristic not always the best way to determine genetic difference
Many characteristics are polygenic and environmental factors will play a role
Define polygenic
A characteristic that is determined by multiple genes
What are the different ways of investigating diversity
Observable characteristics DNA base sequences MRNA base sequence Amino acid sequence Immunological proteins
How are genes compared using DNA base sequencing
DNA extracted
Gene isolated
Sequenced and compared
Why do two species have different DNA base sequences of the same gene
Before speciation they had the same bases
Overtime mutations to gene accumulate
Eventually they are very different
Why can the Amino acid sequence of a particular protein be used to investigate diversity
Proteins are coded for by bases on DNA so similar proteins = similar DNA
Why is DNA base sequencing more reliable than comparing amino acid sequences
DNA is degenerate so same Amino acid may be coded for by multiple triplets.
So may be wide variation in possible base sequences of gene
Why can Immunological comparison be used to investigate diversity
Antidodies are coded for by DNA (they are proteins) and have specific shape depending on DNA.
Similar genes =similar 3D structure = antigen antibody complex forms
Describe how Immunological comparisons are made
You want to compare species A and C
Extract albumin of A and place in Species B.
Species B will produce antibodies to proteins in A.
Collect antibodies and purify and add to blood of C.
Antigen antibody complexes will form.
More similar genes = more similar 3D shape of antigens = more complexes= more precipitate
What is albumin
Soluble proteins extracted from blood
Define interspecific variation
Variation between individuals of different species
Define intraspecific variation
Variation between individuals of same species
Explain the difference between population and sample
Population = all members
Sample= smaller group within population that is representative
Define random sampling
Picking a sample from a population without bias
Suggest how you can take a random sample
Divide up an area into atleast 10 quadrats and use a random number generator to choose 5 coordinates.
Choose all organisms in quadrat
Why might a sample not be representative
Sampling bias
Chance
How can chance be minimised
Use a large sample size
Data analysis (determine whether comparison is due to chance)
Repeats and means
How can bias be minimised
Use random sampling
Why does having a large sample size solve the problem of chance
Reduces the effect of anomalies
Describe the shape of normal Distribution
Bell shaped
Varies in max height and width
Mean=median= mode
Data is spread evenly around mean
What is the advantages and disadvantages of using the mean
Takes into account all values
Doesn’t show range
What is the advantages and disadvantages of standard deviation
Takes into account all data
Shows how spread around mean
Reduces influence of extremes
What can we use the SD for
To determine how statistically significant the deference between two variable is
To determine how reliable the mean is
What % of data is within 1 SD in normal Distribution
68%
What % of data is within 2 SD in normal Distribution
95
What % of data is within 3 SD in normal Distribution
98
What’s the difference between range and error bars
Range bars are not symmetrical and span from highest to lowest value
Error bars are symmetrical and range from +1 SD and - 1 SD, doesn’t take into account extremes
What is SRCC
A measure to determine how correlated two variables are
What is the student t test
A measure to compare means
What is the chi squared test
Measure to compare sample to expected
