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 can 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, or 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 if handwritten
2) The 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 breeding
Organisms form a pair bond
Synchronise mating
What must a prospective mate be?
Mature and fertile
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?
Based 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?
Another common ancestor from which a 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 organism
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 cell walls (if applicable)
Larger ribosomes than bacteria and archaea
Membranes 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 different species and the number of individuals of each species with any one community
What is genetic diversity?
The variety of genes possessed by the individuals that make up a population of a species
What is ecosystem diversity?
The range of different habitats, from a small local habitat to the whole of the year
What is species richness?
The number of different species in a particular area of a given community
How do you measure species diversity?
Use the index of diversity calculation
What is the index of diversity calculation?
d= N(N-1)/total n(n-1)
What is the impact of agriculture?
Farmers select species for particular qualities and that make them more productive therefore the number of species and the genetic variation of alleles they possess is reduced to few that exhibit to the desired features.
Any particular area can only support a certain amount of biomass. Hence when one area is taken up by one species there is a small area available for the other species. There is a reduction in the index of species diversity .
What reduces species diversity?
- The removal of hedgerows
- creating monocultural
- Filling in ponds and draining marshes
- Overgrazing of land
- using pesticides and inorganic fertiliser
- Escape of effluent from silage stores
- Absence of crop rotation and lack of intercropping
How can you conserve the impact of agriculture’s?
- maintain existing hedgerows
- Plant hedges rather than erect fences
- Maintain existing ponds/create new ones
- Leave wet corners of fields than draining them
- Plants native trees on land with a low species diversity
- Reduce the use of pesticides
- Use organic fertilisers
- Use crop rotation (including nitrogen – fixing crop) which improves soil fertility
- create natural meadows
- Leave the cutting of verges and filled edges until after the seeds have dispersed
Why is it important to maintain biodiversity?
If biodiversity is reduced the global living system becomes increasingly unstable and then we have to rely on global systems for food and other resources
How can observable characteristics help to classify organisms?
You observe the characteristics of an organism and then group them depending on this due to these characteristics are determined by a gene with environmental influences
Why are there limitations with using observable characteristics to help us classify organisms?
The characteristics had a large number of genes which are polygenetic meaning they are not discrete from one another but rather vary continuous
Characteristics can be modified by environmental influences
How do you compare the DNA of different species
The nucleotides in the DNA can be tagged with different coloured fluorescent dyes.
The more similar the sequence of DNA nucleotide bases the most similarity in the DNA between the two species hence they are more related.
How can you compare the base sequence of mRNA of different species?
In the same way as comparing the DNA sequence
How can you compare species by the amino acid sequence in proteins?
The degree of similarity in the amino acid sequence of the same protein into species or affect how closely related to each species.
Describe the immunological comparison of proteins process
1) serum (containing the protein) from species A is injected into species B
2) serum B produces specific antibodies with specific antigen site
3) Serum is extracted from species B (containing antibodies)
4) antigens from species C correspondence to antibodies
5) The response forms a precipitation
6) The most similar antigens, the more precipitation is formed
7) The more closely the species are related
Why is random sampling important?
Reduces bias/to eliminate any human involvement in choosing samples
How can you carry out a random sample?
One) divide the study area in to quadrates
Two) number the quadrates
Three) use a random number generator
Four) take samples of those numbers stated
How can you remove chance?
Use a large sample size – the more individuals that are selected the smaller the probability that chance will influence the result
What is standard deviation?
It’s the measure of the width of the curve giving an indication of the range of values either side of the mean
How do you calculate the standard deviation?
S= Square root[Total (X - (mean)^2)/n-1]
