Chapter 34 - Vertebrates Flashcards
1) Chordate pharyngeal slits appear to have functioned first as:
A) the digestive system's opening. B) suspension-feeding devices. C) components of the jaw. D) gill slits for respiration. E) portions of the inner ear.
B) suspension-feeding devices.
Which of the following statements would be least acceptable to most zoologists?
A) The extant lancelets are contemporaries, not ancestors, of vertebrates.
B) The first fossils resembling lancelets appeared in the fossil record around 530 million years ago.
C) Recent work in molecular systematics supports the hypothesis that lancelets are the most recent common ancestor of all vertebrates.
D) The extant lancelets are the immediate ancestors of the fishes.
E) Lancelets display the same method of swimming as do fishes.
D) The extant lancelets are the immediate ancestors of the fishes.
Which extant chordates are postulated to be most like the earliest chordates in appearance?
A) lancelets B) adult tunicates C) amphibians D) reptiles E) chondrichthyans
A) lancelets
A new species of aquatic chordate is discovered that closely resembles an ancient form. It has the following characteristics: external armor of bony plates, no paired lateral fins, and a suspension-feeding mode of nutrition. In addition to these, it will probably have which of the following characteristics?
A) legs
B) no jaws
C) an amniotic egg
D) endothermy
B) no jaws
How many of the following statements about craniates is (are) correct?
- Craniates are more highly cephalized than are noncraniates.
- Craniates’ genomic evolution includes duplication of clusters of genes that code for transcription factors.
- The craniate clade is synonymous with the vertebrate clade.
- Pharyngeal slits that play important roles in gas exchange originated in craniates.
- The two-chambered heart originated with the early craniates.
A) one of these B) two of these C) three of these D) four of these E) five of these
D) four of these
What do all craniates have that earlier chordates did not have?
A) brain B) vertebrae C) cartilaginous pipe surrounding notochord D) partial or complete skull E) bone
D) partial or complete skull
Lampreys differ from hagfishes in:
A) lacking jaws.
B) having a cranium.
C) having pharyngeal clefts that develop into pharyngeal slits.
D) having a notochord throughout life.
E) having a notochord that is surrounded by a tube of cartilage.
E) having a notochord that is surrounded by a tube of cartilage.
The earliest known mineralized structures in vertebrates are associated with which function?
A) reproduction B) feeding C) locomotion D) defense E) respiration
B) feeding
A team of researchers has developed a poison that has proven effective against lamprey larvae in freshwater cultures. The poison is ingested and causes paralysis by detaching segmental muscles from the skeletal elements. The team wants to test the poison’s effectiveness in streams feeding Lake Michigan, but one critic worries about potential effects on lancelets, which are similar to lampreys in many ways. Why is this concern misplaced?
A) A chemical poisonous to lampreys could not also be toxic to organisms as ancestral as lancelets.
B) Lamprey larvae and lancelets have very different feeding mechanisms.
C) Lancelets do not have segmental muscles.
D) Lancelets live only in saltwater environments.
E) Lancelets and lamprey larvae eat different kinds of food.
D) Lancelets live only in saltwater environments.
The lamprey species whose larvae live in freshwater streams, but whose adults live most of their lives in seawater, are similar in this respect to certain species of
A) chondrichthyans. B) actinopterygians. C) lungfishes. D) coelacanths. E) hagfishes.
B) actinopterygians.
Jaws first occurred in which extant group of fishes?
A) lampreys B) chondrichthyans C) ray-finned fishes D) lungfishes E) placoderms
B) chondrichthyans
Which of these might have been observed in the common ancestor of chondrichthyans and osteichthyans?
A) a mineralized, bony skeleton B) opercula C) bony fin rays D) a spiral valve intestine E) a swim bladder
A) a mineralized, bony skeleton
To which of the following are the scales of chondrichthyans most closely related in a structural sense?
A) osteichthyan scales B) reptilian scales C) mammalian scales D) bird scales E) chondrichthyan teeth
E) chondrichthyan teeth
Which of these statements accurately describes a similarity between sharks and ray-finned fishes?
A) The skin is typically covered by flattened bony scales.
B) They are equally able to exchange gases with the environment while stationary.
C) They are highly maneuverable due to their flexibility.
D) They have a lateral line that is sensitive to changes in water pressure.
E) A swim bladder helps control buoyancy.
D) They have a lateral line that is sensitive to changes in water pressure.
Which group’s members have had both lungs and gills during their adult lives?
A) sharks, skates, and rays B) lungfishes C) lancelets D) amphibians E) ichthyosaurs and plesiosaurs
B) lungfishes