Biological Keys

Identifying the unknown

Separate this lab equipment into two groups using their physical properties.

Goggles Test tube holder

Bunsen burner Beaker

Biological keys

Lab equipment

Made of metal Made of non metal

Made of two different metals Made of only one metal Has a scale Has no scale

Bunsen burner Test tube holder Beaker Goggles

Separate these plants into two groups

1 2

3 4

Biological keys

Plants

Plants with flowers Plants with out flowers

Plant with pink flowers Plant without pink flowers Plant with thick leaves Plant without thick leaves

4 3 1 2

Biological Keys

Horse Crab

Fish Worm

Biological Keys – branch diagrams

Animals

Has legs Has no legs

Has 4 legs or less Has more than 4 legs Has fins Has no fins

FishHorse crab worm

Branching keys using information from a table

Pupil Hair Colour Freckles Glasses

John Black Yes Yes

Alan Black No Yes

David Brown No No

Peter Black Yes No

Biological keys

Pupils

Wears glasses No glasses

Has freckles No Freckles

John Alan

Brown hair Doesn’t have brown hair

David Peter

Identifying the unknown

A = Toothed wrack B = Bladder wrack C = Egg wrack D = Flat wrack

A = Clam

B = Periwinkle

C = Tower shell

D = Razor shell

Organisms

Legs/no legs Shell/no shell Feelers/no feelers Varies in width/same

width Line down body/no

line down body Saddle/ no saddle

Organisms keyOrganisms

No legs Has legs

BHas feelers Has no feelers

Has a saddle Has no saddle

A E

Body same width Body varied width

Has a centre line Has no centre line D

C F

Leaves

Leaflets(A,B&F)/no leaflets

Leaflets fan shaped (B)/not fan shaped

4 pairs of leaflets (F)/more than 4 pairs of leaflets (A)

Smooth edge (D)/ no smooth edge

Lobes (C)/ no lobes Serrated edge (E &H)/ no

serrated edge

Leaves keyLeaves

Has leaflets Has no leaflets

Paired leaflets No paired leaflets

4 leaflet pairs More than 4 leaflet pairs

F A

Has lobes Has no lobes

Has smooth edge No smooth edge

D Has serrated edge Has no serrated edge

H G

B Has rounded lobes Has pointed lobes

C E

Paired Statement Keys

Paired statement keys work in the same way as branching keys.

At each stage you are given a choice.Make the appropriate choice and go to

where you are asked to go.Again, if the organism is present, you

should end up with a name for it.

Paired Statement Key1. Single leaf go to 2

Several leaflets go to 6

2. Leaf with prickles HOLLY

Leaf with no prickles go to 3

6. Leaflets in fan shape HORSE CHESTNUT

Leaflets in pairs go to 7

3. Leaf edge with lobes go to 4

Leaf edge with no lobes go to 5

4. Lobes sharp pointedSYCAMORE

Lobes rounded OAK5. Leaf with smooth edge BEECH

Leaf with serrated edge ELM

7. Leaf edge serrated ROWAN

Leaf edge plain ASH

Keys

The paired statement key is more manageable as it tends not to spread itself out as much.

The branching key is more pictorial and usually easier to use.

Try building your own keys for the following organisms. (Branching and Paired Statement!)

Tulip Cockle Sycamore

Dandelion

Giraffe Gold finch Mackerel Seaweed

Spider Sea Urchin

Venus Fly Trap Cockatoo