Diversity and Classification Flashcards
The way in which living organisms are divided into groups
Classification
The scientific practice of grouping organisms based on shared characteristics
Taxonomy
Large groups that are divided into progressively smaller groups with no overlap between the groups
Hierarchical system
Based on evolutionary history of organisms
i.e. their common ancestry
Phylogenetic
Species…
A group of organisms with similar characteristics that can interbreed to produce fertile offspring
Did King Phillip Come Over For German Sausages
Domain Kingdom Phylum Class Order Family Genus Species
Family taxonomic rank ends in…
ae
Clarifying evolutionary relationships through:
- Genome Sequencing
- Comparing amino acids
- Immunological comparisons
Genome sequencing…
Entire base sequence of DNA can be compared to another piece of DNA to see how closely related they are - similarity of bases or not
Comparing amino acids is…
when the sequence of amino acids in a protein is coded for by the base sequence in DNA
Immunological comparison are…
when similar proteins will also bind to the same antibodies
Infertile offspring cannot undergo meiosis. Why?
Odd number of homologous chromosomes to pair up so no gametes are formed.
Give three problems in classifying organisms as distinct species
- Most species did not leave fossils
- Considerable variation with any one species
- Cannot be tested on organisms that use asexual reproduction
Why is Courtship Behaviour useful for investigating species?
It can identify members of the same species who can produce fertile offspring
Give two ways in which courtship increases the probability of successful mating?
- Enables recognition of the same species
- Indicates if they are fertile
- Formation of a pair bond
- Organism is sexually mature
Give two features that are characteristics of the kingdom Fungi
- The cell wall is made of chitin
2. They have hyphae
Give two other sources which scientists may have used to classify cheetahs and leopards in different genera
- Evolutionary history
- Fossils
- DNA base sequence comparison
- Comparison of amino acid sequences
All the organism in a habitat
Community
All the organism of one species in a habitat
Population
What two things do you need to know to calculate species diversity?
- Total number of organisms of all species
2. Total number of organisms of a particular species
High diversity =
biotic factors favour + stable environment
Rainforest/woodland > greater variety of food and habitats and plants
Low diversity =
abiotic factors favour + unstable environment
Desert/arctic > poor variety of food and habitats and plants
Sampling a community to calculate Species Diversity index we need to:
- Select a random area to grid > prevent bias
- Grid the area
- Use random table generator to gain the coordinates
- Use a quadrat > number of species counted
- Repeat x10
How does agriculture provide ideal conditions for crop photosynthesis and growth?
- Fertilisers provide minerals
- Fields irrigated so there is enough water
- Certain fast growing crop species are selected
Examples of conservation techniques used by farmers are:
- Maintenance of existing hedgerows
- Maintain ponds
- Reduce the use of pesticides
- Create natural meadows
Random sampling is used to…
ensure that every member of the population has ne equal chance of being included in the sample > avoids bias
Large samples are used…
as it minimises the influence of chance and allows a Species Diversity Index to be calculated
Standard deviation is…
the spread around the mean and can indicate reliability
Overlap = no significant difference
No Overlap = is a significant difference
