Chapter 15: Vertebrate Beginnings- Chordates

Question 1

What is a notochord?

Answer 1

flexible rod that extends the length of the body, allows lateral undulations and muscles attach to it.

Question 2

What does the Dorsal Hollow Nerve Cord form?

Answer 2

The Brain in Vertebrates

Question 3

What is Pharyngeal Gill Slits? What did they evolve for?

Answer 3

perforated pharynx, evolved for filter feeding, gives rise to a variety of structures; lead to outside animals body.

Question 4

What is an Endostyle?

Answer 4

secretes mucus that traps food particles into pharyngeal cavity, efficient for filter-feeding.

Question 5

What is the Postanal Tail? What did it evolve for?

Answer 5

evolved for propulsion in water; located behind anus.

Question 6

What the two siphons in Subphylum Urochordata? What do they do?

Answer 6

Incurrent- water enters
Excurrent- water exits

Question 7

What are three features of chordates that are also seen in non-chordate invertebrates?

Answer 7

All Bilateral symmetry, all coelomates, all have cephalization.

Question 8

List the three subphyla included in Phylum Chordata.

Answer 8

Urochordata, Cephalochordata, Vertebrata