Trilobites

Question 1

trilobites range

Answer 1

cambrian - permian

Question 2

trilobite PHYLUM

Answer 2

anthropoda

Question 3

trilobites CLASS

Answer 3

trilobita

Question 4

trilobites head

Answer 4

cephalon

Question 5

trilobites middle

Answer 5

thorax

Question 6

trilobites tail

Answer 6

pygidium

Question 7

what is the exoskeleton of a trilobite made of

Answer 7

chitin

Question 8

what were trilobite legs called

Answer 8

appendages

Question 9

what was the free cheek of trilobites

Answer 9

part of the cephalon that breaks away from the skeleton during ecdysis

Question 10

what is ECDYSIS

Answer 10

moulting/shedding skin

Question 11

what were antenna in trilobites

Answer 11

to detect environment

Question 12

what is glabella in a trilobite

Answer 12

part of cephalon (head) which may indicate diet

Question 13

what iis a trilobite compound eye

Answer 13

an eye made up many calcite plates for vision

Question 14

what is a trilobite facial suture

Answer 14

line of weakness along which the exoskeleton breaks away during ecdysis

Question 15

what is the trilobite fixed cheek

Answer 15

part of cephalon(head) that stays attached to skeleton at the START of ecdysis

Question 16

what is the trilobite pygdium

Answer 16

tali - may have spines
used to stabalise the animal
made of fused segments

Question 17

what is the trilobite genal angle

Answer 17

part of cephalon (head) which may have spines attached

Question 18

what is trilobite axis

Answer 18

central lobe running down the length of the trilobite extension

Question 19

what were features of benthonic trilobite

Answer 19

many pleura - many legs for walking
crescent shaped eyes - can see above in all directions - lived on sea floor
large and not streamlined - did not swim

Question 20

what is an example of a benthonic trilobite

Answer 20

calymene

Question 21

define epifaunal

Answer 21

bottom dwelling - living on top of substrate or sediment

Question 22

define infaunal

Answer 22

living in the sediment, burrowing

Question 23

what were the features of planktonic trilobites

Answer 23

small - stay afloat in water
no/small eyes - animal did not hunt, either filter fed or ate organic rich sediment
inflated glabella - floatation mechanism
few pleura - few legs maybe paddle mechanism

Question 24

what is plueron in a trilobite

Answer 24

a segment adjoining the axis

Question 25

what is an example of a PLANKTONIC trilobite

Answer 25

Agnostus

Question 26

what are the features of a NECKTONIC trilobite

Answer 26

eyes on stalk - can look all directions including below
inflated glabella - floation device
very small - floating
numerous separated pleura - many legs to swim - separate to aid buoyancy

Question 27

what does PLANKTONIC mean

Answer 27

floating in the water column

Question 28

what BENTHONIC mean

Answer 28

live on or in sediment or substrate

Question 29

what does NECKTONIC mean

Answer 29

actively swimming in water column

Question 30

what is an example of a NECKTONIC trilobite

Answer 30

deiphon

Question 31

what are the features of BURROWING trilobite

Answer 31

no eyes (blind) - no hunting, food source organic rich sediment
wide cephalic fringe - spread mass on soft sediment/burrow
extended genal spines - spread mass, defence
pitted cephalic fringe - sensory hair holders in life to detect prey or water currents

Question 32

example of BURROWING trilobite

Answer 32

trinucleus