IAG_29.docx!!!!!!!!!!!!!!!! IAG_29.docx IAG_29.docx
OpenStax Biology 2e Instructor Answer Guide
Biology
Unit 5: Biological Diversity
Chapter 29: Vertebrates
Visual Connection Questions
1. Which of the following statements about common features of chordates is true?
a. The dorsal hollow nerve cord is part of the chordate central nervous system.
2. Which of the following statements about the parts of an egg are false?
d. The amniotic cavity is filled with albumen.
IAG_29.docx 4/20/2026, 2:15:29 PM IAG_29.docx
, IAG_29.docx!!!!!!!!!!!!!!!! IAG_29.docx IAG_29.docx
OpenStax Biology 2e Instructor Answer Guide
3. Members of the order Testudines have an anapsid-like skull without obvious temporal
fenestrae. However, molecular studies indicate that turtles descended from a diapsid ancestor.
Why might this be the case?
The ancestor of modern Testudines may at one time have had a second opening in the skull,
but over time this might have been lost.
Review Questions
4. Which of the following is not contained in phylum Chordata?
b. Echinodermata
5. Which group of invertebrates is most closely related to vertebrates?
a. cephalochordates
6. Hagfish, lampreys, sharks, and tuna are all chordates that can also be classified into
which group?
a. Craniates
7. Members of Chondrichthyes differ from members of Osteichthyes by having a ________.
c. cartilaginous skeleton
8. Members of Chondrichthyes are thought to be descended from fishes that had ________.
b. a bony skeleton
9. A marine biologist catches a species of fish she has never seen before. Upon examination,
she determines that the species has a predominantly cartilaginous skeleton and a swim
bladder. If its pectoral fins are not fused with its head, to which category of fish does the
specimen belong?
b. Osteichthyes
IAG_29.docx 4/20/2026, 2:15:29 PM IAG_29.docx
OpenStax Biology 2e Instructor Answer Guide
Biology
Unit 5: Biological Diversity
Chapter 29: Vertebrates
Visual Connection Questions
1. Which of the following statements about common features of chordates is true?
a. The dorsal hollow nerve cord is part of the chordate central nervous system.
2. Which of the following statements about the parts of an egg are false?
d. The amniotic cavity is filled with albumen.
IAG_29.docx 4/20/2026, 2:15:29 PM IAG_29.docx
, IAG_29.docx!!!!!!!!!!!!!!!! IAG_29.docx IAG_29.docx
OpenStax Biology 2e Instructor Answer Guide
3. Members of the order Testudines have an anapsid-like skull without obvious temporal
fenestrae. However, molecular studies indicate that turtles descended from a diapsid ancestor.
Why might this be the case?
The ancestor of modern Testudines may at one time have had a second opening in the skull,
but over time this might have been lost.
Review Questions
4. Which of the following is not contained in phylum Chordata?
b. Echinodermata
5. Which group of invertebrates is most closely related to vertebrates?
a. cephalochordates
6. Hagfish, lampreys, sharks, and tuna are all chordates that can also be classified into
which group?
a. Craniates
7. Members of Chondrichthyes differ from members of Osteichthyes by having a ________.
c. cartilaginous skeleton
8. Members of Chondrichthyes are thought to be descended from fishes that had ________.
b. a bony skeleton
9. A marine biologist catches a species of fish she has never seen before. Upon examination,
she determines that the species has a predominantly cartilaginous skeleton and a swim
bladder. If its pectoral fins are not fused with its head, to which category of fish does the
specimen belong?
b. Osteichthyes
IAG_29.docx 4/20/2026, 2:15:29 PM IAG_29.docx
