1. Cambridge IGCSE Biology
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Cambridge IGCSE Biology
Classification and Keys

2. You will need to be able to:
Define and describe the binomial system of naming species
Use a dichotomous key to identify an unknown organism

3. Biological classification:
Kingdom
Phylum
Class
Order
Family
Genus
Species
Animalia
Chordata
Mammalia
Carnivore
Felidae
Panthera
pardus
Taxonomic
ranks
Panthera pardus

4. The binomial system gives organisms a two word name showing the genus and species
Panthera leo
Panthera tigris
Panthera pardus

5. There are other classification systems:
Cladistics: Based on similarity and differences between DNA and RNA sequences
AACA
AGTA
AAAA
AGAA
AGGA
Extended

6. You will need to be able to:
Define and describe the binomial system of naming species
Use a dichotomous key to identify an unknown organism

7. Keys use a series of questions to identify unknown organisms
Identify the fungus
frill
cap
Stalk does not have a frill go to 2 Stalk has a frill go to 3
Stem is brown Fungus A Stem is yellow Fungus B
Cap has spots go to 4 Cap does not have spots Fungus C
Cap is red Fungus D Cap is brown Fungus E

8. Now you should be able to
Define and describe the binomial system of naming species
Use a dichotomous key to identify an unknown organism

9. Cambridge IGCSE Biology