Quiz 2 - Deuterstomes

Question 1

What is the earliest fossil of exhinoderms and deuterstomes found in the ediacaran

Answer 1

Arkarua

Question 2

What dominated the ediacaran fauna? What about the cambrian?

Answer 2

Sponges and diploblasts

Cambrian - arthropods

Question 3

What is the first accepted deuterstome fossil

Answer 3

Vetulicolians

• segmentation, bipartite, gill slits

Question 4

Homalozoans were early deuters .. in the mid cambrian and devonian - they had…

Answer 4

Gill slits, post anal tail, lacked radial symmetry

Question 5

What were the deuterstomes close to hemichordates with a bipartite body, and segmented tail?

Answer 5

Velulocystida

Question 6

What were similar to the velulocystids (close to hemichordates)?

Answer 6

Stylophorans

Question 7

What were the two interpretations of early echinoderms

Answer 7

Enchino w early feeding arm

Or

Echino pre-radial w hemichordate stalk

Question 8

The yanjiahella was found between the….

Answer 8

Echino and hemichordate

Question 9

What was the earliest accepted hemichordate from the lower cambrian

Answer 9

Yunnanozoon

Question 10

What was the fossil with a notochord and segmented musculature?

Answer 10

Pikaia

Question 11

What was the chordate fossil that lacked a cranium?

Answer 11

Haikouella

Question 12

What belongs to the ambulacraria?

Answer 12

Echinoderm

Hemichordate

Question 13

What phyla of ambulacraria are exclusively marine, benthic, macroscopic?

Answer 13

Echinoderms

Question 14

What is different between the forms of paleozoic echinos and modern echinos?

Answer 14

Paleo - sessile

Modern - motile

Question 15

What is the most ancient class of echinos

Answer 15

Crinoidea

Sea lillies and sea feathers

Question 16

Describe the sea lillies and sea feathers… what class? Where are they found? How to they use their tube feet?

Answer 16

Crinoidea - ancient class

All benthic

Tube feed for suspension feeding

Question 17

What class do sea stars belong to

Answer 17

Asteroidea

Question 18

What is benthic, found at all depths, pentaradial, predatory and scavenger?

Answer 18

Asteroidea - sea stars

Question 19

What class do brittle stars belong to?

Answer 19

Ophiuroidea

Question 20

What species are found in class echinoidea?

Answer 20

Sea urchins and sand dollars

Question 21

For sea urchins and sand $, what gives them their pentaradial symmetry

Answer 21

Fused skeletal ossicles

Question 22

What is the regular form of echinoidieans?

Answer 22

Sea urchins

Long movable spines
Move w tube feet + spines
Pedicellariae for cleaning and defense

Question 23

What is the irregular form of echinoidieans?

Answer 23

Sand $ form

Short spines for locomotion + free sediment, secondary bilateral symmetry for digging and burrowing

Question 24

What class are sea cucumbers in?

Answer 24

Holothuroidea

Question 25

How did sea cucumbers get bilateral symmetry

Answer 25

Secondarily

Question 26

How to cucumbers eat

Answer 26

Suspension feed / deposit feed using tentacles + mucus

Question 27

How to cucumbers move?

Answer 27

Ventral tube feet + body muscles

Question 28

What are hemichordate

Answer 28

Marine Benthic Macroscopic Motile or sessile

Question 29

What are the 5 classes of sea stars

Answer 29

``` Crinoidea (sea lillies + feathers) Asteroidea (sea star) Ophiuroidea (brittle) Echinoidea (urchins + sand $) Holothuroidea (cucumbers) ```

Question 30

What are the two classes of hemichordates?

Answer 30

Pterobramchia Enteropneusta (acorn worms)

Question 31

Describe pterobranchia

Answer 31

Tube dwelling colonial animals Looks like bryozoans, superficially Tripartite body

Question 32

Describe enteropneusta

Answer 32

Acorn worms Solitary, sediment dwelling Tripartite Feed on sediment particles

Question 33

What are the characteristics of ambulacraria

Answer 33

Tripartite bodies (and coeloms) Axial complexity Larval forms free swimming, bilateral, soft bodied, ciliated

Question 34

What surrounds the viscera (internal, organs) and contains the watery coelomic fluid (Ambulacraria)

Answer 34

Pervisceral coelom

Question 35

All ambulacraria classes have lost this except for the crinoids.. what is it

Answer 35

Hydrocoel

Question 36

What makes the WVS in ambulacraria

Answer 36

Isolated portion of coelom

Question 37

Hemichordate have a proboscis, stalk and collar... what is the protocoel?

Answer 37

Space insider proboscis mostly muscles fibers

Question 38

What is the difference in axial complexity in echinoderms and hemichordates?

Answer 38

Echinos - junction of perivisceral coelom, WVS, + hemal coelom Hemichordates - heart kidney complex

Question 39

What are the 6 characteristics of echinoderms

Answer 39

``` Endoskeleton Pedicellariae (pincers) Dermal branchiae / papulae WVS pentaradial symmetry Ambulacra grooves ```

Question 40

What is the endo skeleton of enchinoderms made up of?

Answer 40

Skeletal ossicles | Calcium carbonate makes the stereom

Question 41

How does the endo skeleton of holothuroidea differ from other echinos?

Answer 41

Lost bulky plates, but have microscopic plates instead

Question 42

Describe what the pedicellariae do in enchinos

Answer 42

Dorsal side 3-forceps like extensions, cut off larvae / pinch Looks like long stalk w bulbous head w 3 valves

Question 43

The pedicellariae are found where

Answer 43

Base of spine

Question 44

What do the 3 valves of pedicellariae do?

Answer 44

Act like jaws that snap at anything the touches their sensor

Question 45

What is the dermal branchiae

Answer 45

Thin folds of body wall Extend btw ossicles Used for gas exchange

Question 46

What is the function of papulae / dermal branchiae

Answer 46

Gas exchange/ respiration Thought of like gills on the skin of echinos - thin fold of the body wall, extend btw ossicles

Question 47

The WVS of echinos extends from the body surface as a series of tentacles projecting... what are these projections / extensions

Answer 47

Tube feet / podia

Question 48

What were tube feet originally evolved for?

Answer 48

Feeding first, then locomotion

Question 49

How do the tube connect to the outside?

Answer 49

Via the madreporite

Question 50

What is the function of polian vessicles?

Answer 50

Maintain internal pressure

Question 51

The radial canals extend down what...

Answer 51

Down the ambulacral grooves

Question 52

Where to lateral canals lead to?

Answer 52

Tube feet

Question 53

How to tube feet extend from the echino?

Answer 53

Hydrostatic pressure via ampullae Ampullae move water into tube feet

Question 54

List the different parts of echino WVS

Answer 54

Podia / tube feet Connects to the outside via madreporite Polian vessicle - internal pressure Radial/ring canals - extend down ambulacra Lateral canals - lead to tube feet Ampullae - pull water into tube feet Tube feet extend via hydrostatic pressure

Question 55

What is pentaradial symmetry in echinoderm linked to?

Answer 55

Sessile lifestyle of ancestor

Question 56

What is different about the symmetry of sea urchins and sand dollars (Ophiuroidea)

Answer 56

Superimposed bilateral symmetry on pentaradial symmetry

Question 57

How is pentaradial symmetry developped in echinos upon metamorphosis

Answer 57

Metamorphosis of echinos makes larva The left side of larva develops into adult + makes oral side Right side is absorbed

Question 58

How to asteroideans develop the WVS + canals

Answer 58

Coelom cavity makes a U shape Coelomic parts separate Form WVS + canals

Question 59

How do echinos develop What are the 2 larval stages

Answer 59

1 - ciliated bands cover bipinnarial function in locomotion + feeding 2 - brachiolaria Larva grows 3 adhesive arms + sucks to attach to surfaces Larva then metamorphosis

Question 60

What classes have ambulcra grooves restricted to the oral surface

Answer 60

Crinoids Asteroidea Ophiuroidea

Question 61

What classes have ambulcra grooves that extend oral to aboral, and lack arms

Answer 61

Echinoidea | Holothuiroidea

Question 62

What did echinos likely descend from?

Answer 62

Bilateral ancestors that evolved radially for a sessile lifestyle

Question 63

What fossils lacks 5 fold symmetry but has spiral grooves indicative of ambulacral groove

Answer 63

Heliocoplacus

Question 64

What extinct class of echinos was sessile with thick stalk + plates that had pentaradial symmetry

Answer 64

Edrioasteroidea

Question 65

What were the oldest group of echinos that had starfish and brittle star characters

Answer 65

Asterozoans

Question 66

What was the hemichordate fossil that looked like tiny saw blades with tubes similar to pterobranchia

Answer 66

Grapolithina (extinct)

Question 67

What are some characteristics of hemichordates similar to chordates

Answer 67

Branchial opening (gill slits) that open into the pharynx Stomochord Dorsal nerve chord + smaller ventral nerve chords Tripartite body