Chapter 34: Origin and Evolution of Vertebrates

Question 1

Single hollow nerve chords

Answer 1

runs just beneath the dorsal surface of chordata.

Question 2

What does the single hollow nerve chords differentiate into within mammals

Answer 2

brain and spinal cord

Question 3

Notocord

Answer 3

a flexible rod that form on the dorsal side of the primitive gut in the early embryo and is present in some developmental stages in all chordates

Question 4

What does the notochord differentiate into within mammals

Answer 4

spinal column that surrounds the nerve cord

Question 5

Pharyhgeal gill slits

Answer 5

connect the pharynx to the external environment; maybe called pouches in terrestrial chordates because it does not connect it to the outside Pharyhgeal gill slits connect the pharynx to the external environment; maybe called pouches in terrestrial chordates because it does not connect it to the outside.

Question 6

Post anal tail

Answer 6

extends beyond the anus, at least during embryonic development

Question 7

What are the three subphylum of chordata?

Answer 7

cephalochordate
Urochordata
Vertebrata

Question 8

What Cephalochordata is also commonly known as what?

Answer 8

Lancelot

Question 9

Describe some of the most important characteristics of the Lancelot skin? (3) and other important characteristics? (2)

Answer 9

1. no pigment
2. 1 cell layer thick
3. scaleless
4. no distinguishable head
5. pharyngeal slits used for filter feeding

Question 10

What is the common name of Urochordata?

Answer 10

Tunicate

Question 11

Urochordata are only considered chordates because of their _____ stage

Answer 11

larva

Question 12

What adult stage of chordata have a sessile adult stage with no major body cavity or segmentation?

Answer 12

Urochordata

Question 13

What clade has two or more sets of hoxgenes?

Answer 13

vertebrata

Question 14

What is the synapomorphy of cephalochordate?

Answer 14

Notochord

Question 15

What is the first clade to have a cranium?

Answer 15

vertebrata

Question 16

What are the Neuro Crest Cells that are found in Vertebrata

Answer 16

a collection of cells that appears near the dorsal margins of the closing neural tube in an embryo

Question 17

What are the Myomeres that are found in Vertebrata

Answer 17

striated muscles they are w shaped

Question 18

What is unique about the vertebrate heart?

Answer 18

2 chambered

Question 19

What is the first clade that has blood w/ hemoglobin and kidneys that remove waste product?

Answer 19

vertebrata