phylum chordata

Question 1

what organisms are the phylum chordata closely related to?

Answer 1

echinoderms

Question 2

what are the two subphylum in the phylum chordata?

Answer 2

cephalochordata and urochordata

Question 3

what are the derived characteristics of chordates? (4)

Answer 3

1) presence of a notochord
2) dorsal, hollow nerve tube
3) pharyngeal slits or clefts
4) post anal tail

Question 4

why is the presence of a notochord important?

Answer 4

provides support for the body, forms part of gelatinous disks b/w vertebrates in humans

Question 5

what organism does the subphylum cephalochordata contain?

Answer 5

lancelets

Question 6

describe the phylogeny of lancelets and the presence of derived characteristics in these organisms

Answer 6

basal group of living chordates, contain all 4 derived characteristics

Question 7

in lancelets, what do their pharyngeal slits act as?

Answer 7

sieve that separates food from water

Question 8

what organism is in the subphylum urochordata?

Answer 8

tunicates (sea squirts)

Question 9

compare the larvae with the adult tunicates

Answer 9

all characteristics are visible in the larva, adults only maintain the pharynx

Question 10

what is the outer covering of tunicates called?

Answer 10

tunics