Name _____________________________
Biology – Block ______
Date _________________
DICHOTOMOUS KEY for the
9 Major Phyla of the Animal Kingdom
1.
A. Asymmetrical, little obvious structure. Body wall has many pores, usually soft to touch . . . .
. .Porifera
B. Has symmetry, and shows definite structures ……………………………….............go to 2
2.
A. Radial symmetry. . . . . . . . . . . . . . . ………….. . . . . . . . .. go to 3
B. Bilateral symmetry or worm-like, or has a shell . . …….. . . go to 4
3.
A. Body soft, may have stinging tentacles…………………………………….………...Cnidaria
B. Body hard and spiny………………………………………………….. . . . . . .Echinodermata
4.
A. 3 or more pairs of appendages, or no appendages (snakes not included)…….. go to 5
B. 2 pairs of appendages, most have backbone………. . . . . . . . . . . . . . . .Chordata
5.
A. Body with jointed appendages & exoskeleton . .. . . . . . . . . . Arthropoda
(like a knight in a suit of armor)
B. Body without jointed appendages . . .. . . . . . . . . . . . . . . . . . . . . . . go to 6
6.
A. Body soft, flattened & worm-like . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Platyhelminthes
B. Body otherwise . . . . . .. . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . go to 7
7.
A. Body with noticeable segments (rings), worm-like . . . . . . . . . . . . . . . . .Annelida
B. Body not obviously segmented . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . go to 8
8.
A. Body long, slender, and smooth, worm-like . . . .. . . . . . …. . . . . . . . .Nematoda
B. Body enclosed in shell and/or with tentacles and/or paired eyes or antennae. . . .Mollusca
Animal Classification Lab – DATA
Directions: 1. Work backwards and identify the characteristics for each animal phylum. 2. Identify
the phylum for each specimen. Write the name of the animal in the corresponding specimen space.
Some rows will have more specimen than others.
Phylum
Characteristics
Specimens
Porifera
Cnidaria
Platyhelminthes
Nemotoda
Annelida
Arthropoda
Mollusca
Echinodermata
Chordata
Name:_____________________________________________Period__________Date__________________
Questions:
1. All of the organisms you saw today belong in Domain ________________________ and
Kingdom ___________________________. You saw five different organisms that belong to
Phylum Chordata. These organisms all belong in separate classes. Which class does each
animal belong to?
Organism
Class
Fish--------------------------- Fish
Frog-------------------------Turtle-----------------------Sparrow--------------------- Birds
Fetal pig---------------------
2. According to the pie graph, which phylum contains the most diverse and successful animals
on the planet? Why do you think they are the most successful?