unit 2.1 - Biodiversity Flashcards
What does the term phylogenic mean?
Evolutionary relatedness
What are taxa?
Levels of classification
What are the different taxa?
Domain - Did
Kingdom - King
Phylum - Phillip
Class - Come
Order - Over
Family - For
Genus - Good
Species - Soup?
Why do we need phylogenetic classification?
- Allows us to infer evolutionary relationships.
- If a new animal is discovered with similar features to a taxa we can predict it’s characteristics using this method
- When describing the health of an ecosystem or the rate of extinction in the geological record, conservations often find it useful to count families than species
What is a domain?
The largest taxon and all living things belong to one of the three domains
What are the 3 domains and their features?
Eubacteria - familiar bacteria e.g E. coli and Salmonella. They are prokaryotes
Eukaryota - includes plantae, animalia, fungi and protoctista. They are all eukaryotic organisms.
Archaea - bacteria that have unusual metabolism e.g some produce methane. They live in marginal habitats and are also prokaryotes
What do domains contain?
Kingdoms
What are the 5 main kingdoms and their features?
- Prokaryota - All bacteria, cyanobacteria, microscopic, single celled organisms with no membrane bound organelles. The cell wall is made out of peptidoglycan or murein
- Protocista - Eukaryotic organisms, single celled, no tissue differentiation.
- Fungi - Heterotrophic eukaryotes with cell wall made from chitin. They reproduce through spores
- Planta - Multicellular eukaryotes, photosynthetic, cellulose cell walls.
- Animalia - Multi cellular eukaryotes, heterotrophic, no cell wall, nervous coordination
What are homologous structures?
- Have a similar arrangement of component parts and a similar developmental origin but different functions e.g the pentadactyl limb - flipper for swimming, wing for flying
What are analogous structures?
- Have a corresponding function but different development origins e.g flipper on a whale or the fin on a shark
What is sexual dimorphism?
Differences in size or appearance of sexes in an animal species e.g mane on a male lion but not on a lioness
How can scientists define a species?
Morphologically - if two organisms look similar they are likely to be the same species
Reproductively - if two organisms can interbreed to produce fertile offspring
What does the term biodiversity mean?
- Number of species or species richness
- Number of individual organisms within each species
What can cause a decrease in biodiversity?
- Succession - organisms change their habitats to make it more suitable for other species
- Human impacts
- Weather
- Disease
- Competition
- Predation
- Availability
- Natural disasters
What is causing the main decrease biodiversity?
Human destruction of habitat is the single greatest threat to biodiversity on the planet
Human activity has made the environments less hospitable to living organisms
What does extinction mean?
Loss of species
Why do we need to protect plants and animals? [4]
- Potential food sources
- Essential raw materials such as cotton, rubber and wood
- Useful chemicals and pharmaceuticals
- Disease resistant genes that can be GMed
What is the calculation for the Simpsons index?
1 - number of each species <divide> total number of organisms
1 - n(n-1)/N(N-1)</divide>
What is a SNP?
One base in the DNA differs
Single Nucleotide polymorphism
What are HVRs and STRs?
Regions of DNA that vary in length, about 20-40 base sequences long often repeated
Hyper Variable Regions + Short Tandem Repeats
What does it mean when a population has a lot of SNPs and HVRs?
More differences indicate a greater biodiversity
What is genetic or DNA profile or fingerprints?
A pattern unique for each individual, related to the base sequence of their DNA
What is adaptive radiation?
The formation of new species from a single common ancestor
What is an anatomical trait?
Give an example in animals and plants
Adaption of a part of an organisms anatomy.
- Sharks and dolphins have streamlined bodies
- Plants have flowers with honey or nectar guides called beelines
