BSC 2011 Vertebrates

Characteristics of all chordates at some point in their development are:

• Dorsal nerve cord, pharyngeal gill slits, post-anterior tail, and notochord

• Dorsal nerve cord, post-anal tail and notochord

• Dorsal nerve cord, notochord, pharyngeal gill slits, and post-anal tail

• Ventral nerve cord, notochord, pharyngeal gill slits and post-anal tail

Which of the following animals is NOT in subphylum vertebrata?

• Fishes

• Amphibians

• Tunicates

• Osteichthyes

• Gnathostomes

One of the most significant evolutionary developments that occured in gnathostomes that allowed them to exploit new food resources was

• Teeth

• hinged jaw

• slimy exterior

• placoid scales

• cartilaginous spine for flexibility

What is a distinctive feature of the chondrichthyans?

• An amniotic egg

• Dorsal fins

• An acute sense of vision

• A cartilaginous skeleton

• Lack of jaws

Which of these statements accurately describes a similarity between sharks and fishes?

• The skin is typically covered by cycloid scales

• They are equally equally able to exchange gases with the environment while stationary.

• All have a high degree of flexibility in the spine and gill slits

• They have a lateral line that is sensitive to electrical impulses

• They have swim bladders to control buoyancy

What are the most abundant and diverse of the extant vertebrates?

• Bony fishes

• Avians

• Amphibians

• Reptiles

The class osteichthyes are characterized by

• A bony endoskeleton, operculum, and a swim bladder

• A cartilaginous endoskeleton

• An amniotic egg

• Teeth that are replaced regularly.

• Ears with three semicircular canals and a swim bladder

Which of these is NOT considered an amniote?

• Amphibians

• Reptiles

• Birds

• Placental mammals

• Egg laying mammals

Why is the amniotic egg considered an important evolutionary breakthrough?

• It has a shell that increases gas exchange

• It allows for the incubation of eggs in a terrestrial environment.

• It prolongs embryonic development

• It provides insulation to conserve heat.

• It permits internal fertilization to be replaced by external fertilization.

Why is the discovery of the fossil Archaeopteryx significant? It supports the

• Phylogenetic relatedness of birds and reptiles

• Idea that birds are much older than trilobites.

• Claim that mammals and dinosaurs coexisted.

• Idea that the first birds were ichthyosaurs

• Hypothesis that some extinct reptiles were endothermic.