Lec 6/7 Part b

Question 1

Urochordata

Answer 1

Sister group of vertebrates (molecular data)

Sexually and asexually reproduce

Having distinct larvae and adult stages

Question 2

Urochordata larva

Answer 2

Tadpole-like swimmer

Two types of larvae:
Filter feeder
Non-feeder

Have all five chordate features

Question 3

Urochordata adult

Answer 3

Filter feeder or ambush predator

Possess tunic covering

Heartbeat reversal periodically

Have three chordate features

Question 4

Urochordata adult types

Answer 4

Pelagic adult

Sedentary adult

Question 5

Diagnostic features of vertebrates

Answer 5

Head with sensory organs, brain, and an internal skeleton

Gills in pharyngeal slits, which become gill slits and lose their role in feeding

Muscles associated with digestive tract, including pharynx; capable of moving food through tract

Muscular heart

Erythrocytes (red blood cells) to transport oxygen in blood stream

Kidneys for regulating fluid and salt balance

Vertebral column

Fins or limbs

Question 6

Muscular heart

Answer 6

Basal chordates relied on contractions of the blood vessels)

Question 7

Vertebral column

Answer 7

Backbone, which is rudimentary in cyclostomes

Question 8

Fins

Answer 8

Not necessarily paired fins, but at least a tail fin

Question 9

Head of vertebrates

Answer 9

Head poorly distinguished from the trunk

Head protected by bony skull

Head separated from trunk

Question 10

Tripartite brain

Answer 10

Enlarged nerve cord (cerebral vesicle)

Three distinct sections (tripartite) of brain

Have 10-12 cranial nerves

Question 11

Neural crest cells and ectodermal placodes

Answer 11

True neural crest cells and ectodermal placodes are unique to vertebrates, although they may have rudimentary homologues in other chordates

Question 12

Neural crest cells form in the vicinity of the ….. in early development

Answer 12

Spinal cord

Question 13

Neural crest cells migrate ….

Answer 13

Throughout the body to contribute to the formation of many structures (eg Jaw)

Question 14

True neural crest cells and ectodermal placodes are unique to

Answer 14

Vertebrates, although they may have rudimentary homologues in other chordates (eg tunicates)

Question 15

Ectodermal placodes are

Answer 15

Tissue buds on the surface of the embryonic head that sink inward to contribute to forming sense organ and nerves (eg lateral line)

Question 16

Gill for respirations

Answer 16

Pharynx used for filter feeding

Pharynx with muscular gill

Pharynx used for feeding and respirations

Question 17

Heart

Answer 17

Tubular heart powered by vessels

Muscular heart with cardiac muscles

Heart with multiple chambers

Question 18

Carrier of respiratory gases

Answer 18

Respiratory gases transported only in interstitial fluid within vessels

Additional oxygen transported by hemoglobins with erythrocytes

Question 19

Kidney

Answer 19

Osmolar concentration within body is equal to external environment

Question 20

Hagfish kidney

Answer 20

Osmolar concentration within the body differ from external environment

Question 21

Vertebral column

Answer 21

Notochord composed of unmineralized tissue (collagen fibres)

Vertebral column composed of mineralized (bones) and unmineralized tissues

Question 22

Fins or limbs

Answer 22

Postanal tail without fin structure