Lophophorates

Question 1

what are the four phyla included in the lophophore group?

Answer 1

Bryozoa, Brachiopoda, Phoronida, Kamptozoa

Question 2

which phyla is the least related to the others amongst the lophophores?

Answer 2

Bryozoa

Question 3

describe a lophophore

Answer 3

• U shaped ring of 1-2 rows of ciliated tentacles
• located around mouth
• each tentacle is an extension of the gut (coelom)
• points posteriorly

Question 4

what functions do lophophores do?

Answer 4

• gas exchange (similar to ctenidia and polychaete polyps)
• food capture
• reproduction (sperm capture and spawning)

Question 5

what traits do phoronids have?

Answer 5

• no cephalization (no brain)
• epistome (lid for selective eating)
• metacoel (single coelomic space in trunk where digestive system is)
• encased in rigid chitinous tube

Question 6

Brachiopoda
where is the anus of a brachiopod relative to the mouth?

Answer 6

dorsal

Question 7

describe a lophophorate trochophore

Answer 7

• has a posterior cilia ring (telotroch, similar to annelid and molluscs)
• long tentacular structures posterior to mouth for feeding/swimming (does not form disc like velagers)
• dorsal side of larva reduces to anus in adult

Question 8

Brachiopoda
what are the two classes of Brachiopoda?

Answer 8

Articulata and Inarticulata

Question 9

Brachiopoda
what are the differences between Articulata and Inarticulata?

Answer 9

Articulata
- hinged, calcium carbonate shell
- no anus, waste exits via mouth
- internal support (brachium)
- short, non muscular pedicle used for adhering to surfaces

Inarticulata
- unhinged calcium phosphate shell
- anus is outside tentacle space
- no internal support
- long muscular pedicle used for burying

Question 10

Brachiopoda
what circulatory system do brachiopods have?

Answer 10

open circulatory (coelomic space)

Question 11

Brachiopoda
what is the difference between how water flows through a brachiopod vs a bivalve

Answer 11

brachiopod: enters through sides and out the anterior
bivalve: enters and exits through posterior (siphons)

Question 12

Bryozoa
what are the three classes of Bryozoa?

Answer 12

Stenolaemata (“narrow throated”), Gymnolaemata (“naked throated”), Phylactolaemata (“guarded throated”)

Question 13

Bryozoa
what order is within the Stenolaemata class?

Answer 13

Cyclostomata

Question 14

Bryozoa
what two orders are within the Gymnolaemata class?

Answer 14

Ctenostomata (flexible cuticle) and Cheilostomata (heavy cuticle)

Question 15

Bryozoa
what traits do Bryozoans have?

Answer 15

• no metanephridia (can diffuse instead)
• colonial structures (zooids)
• developed vascular system for colony
• nervous system

Question 16

Bryozoa
what are the parts of a bryozoan zooid?

Answer 16

cystid = rigid cuticular outer layer
polypide = lophophore + anterior end of trunk (can invert)

Question 17

Bryozoa
what are the three types of zooids found in a Bryozoan?

Answer 17

avicularium (defense)
vibraculum (sweeps around to deter other organisms)
ooecium (broods eggs from feeding zooids)

*all have lost lophophores for other structures

Question 18

Bryozoa
how do bryozoans move?

Answer 18

• vibracula (crawling)
• mucus
• muscular body wall

Question 19

what is the difference between bryozoan and kamptozoan water flow/feeding?

Answer 19

bryozoan = up-down movement
kamptozoan = bottom-up movement

Question 20

Bryozoa
what are the two larval types of bryozoans?

Answer 20

cyphonautes (cone shaped, suspension feeding)
coronates (round, do not feed)

Question 21

what differentiates a bryozoan from a kamptozoan?

Answer 21

kamptozoans have
- no coelom
- protonephridia

bryozoans have
- 3 part coeloms
- no nephridia