trilobites complete

HideShow resource information
Phylum
Arthropoda
1 of 24
Class
Trilobita
2 of 24
evolution
Evolved in cambrian + became extinct at end of the Permian
3 of 24
exoskeleton
made of chitin; provides protection and support; provides attachment for muscles; may have had sensory hairs emerging from the exoskeleton to detect chemicals/changes in the environment
4 of 24
exoskeleton morphology
made up of 3 layers. A waxy outer layer and 2 further layers of chitin and protein. The middle layer may be impregnated with calcium carbonate for increased strength
5 of 24
appendages
term for jointed legs and antennae. used for moving and feeding
6 of 24
pleuron
segment adjoining the axis. each had a pair of jointed legs, probably used for walking or swimming
7 of 24
gills
for respiration. feathery structure used for gas exchange. positioned above the legs, so it didn't drag on the sea floor
8 of 24
Cephalon morphology; Appendages-headlegs
feeding and sensory role to detect environment and feeding
9 of 24
Cephalon morphology; Antenna
to detect environment. part of sensory system
10 of 24
cephalon morphology; Glabella
formed by the presence of the stomach, which is inside the head. shape may indicate diet
11 of 24
cephalon morphology; compound eye
made up of many calcite plates, for wide-angled vision. part of sensory system
12 of 24
cephalon morphology; free cheek
part of cephalon that breaks away from the skeleton during ecdysis
13 of 24
cephalon morphology; facial suture
a line of weakness where the exoskeleton breaks first during ecdysis
14 of 24
cephalon morphology; fixed cheek
part of cephalon that remains attached to the exoskeleton at the beginning of ecdysis
15 of 24
cephalon morphology; genal angle
part of cephalon which may have spines attached. actual angle can be measured in some species
16 of 24
thoracic segment
made up of 3 articulating plates; very flexible; ability to enroll(defensive mechanism)
17 of 24
Thorax morphology
made up of thoracic segments, each possessing a pair of appendages, gills in life and a segment from the axis
18 of 24
thorax morphology; pleuron
segment adjoining axis; may also have spines extending from them
19 of 24
appendages: walking/swimming legs
for locomotion and gill attachment
20 of 24
Pygidium
fused tail piece(several segments fused together); may have spines. this may stabilise the animal
21 of 24
Benthonic
organism lives on or in the sediment substrate of the sea floor/ river bed
22 of 24
infaunal
organism lives in the sediment, usually in a burrow. many will filter feed
23 of 24
epifaunal
organism lives on the sediment substrate
24 of 24

Other cards in this set

Card 2

Front

Class

Back

Trilobita

Card 3

Front

evolution

Back

Preview of the front of card 3

Card 4

Front

exoskeleton

Back

Preview of the front of card 4

Card 5

Front

exoskeleton morphology

Back

Preview of the front of card 5
View more cards

Comments

No comments have yet been made

Similar Geology resources:

See all Geology resources »See all morphology of fossils resources »