CHpt 34? FR

What distinguishes vertebrates from other chordates?

Vertebrates have a backbone.

What are the four derived characters of chordates?

Notochord, dorsal hollow nerve cord, pharyngeal slits, post-anal tail.

What evolutionary innovation led to the development of jaws in vertebrates?

Gnathostomes evolved jaws and mineralized skeletons.

What is a major characteristic of hagfish?

jawless marine scavengers that retain the notochord as adults.

Which vertebrate group includes sharks, rays, and bony fishes?

Gnathostomes.

What adaptation do sharks have for buoyancy?

oil-filled liver.

What are the advantages of jaws in gnathostomes?

Better feeding, stronger predation, and more efficient food processing.

What key evolution allowed vertebrates to reproduce away from water?

The evolution of the amniotic egg.

What are the three groups of amphibians?

Salamanders, frogs, and caecilians.

What distinguishes mammals from other vertebrates?

hair and mammary glands.

Which transitional fossil marks the evolution from fish to tetrapods?

Tiktaalik.

What trait do tetrapods share that distinguishes them from fish?

four limbs with digits.

What are the main characteristics of reptiles?

keratin scales, internal fertilization, and shelled eggs.

What group do birds belong to?

archosaur group, which includes crocodilians and dinosaurs.

Why are amphibians considered sensitive species?

permeable skin and depend on both aquatic and terrestrial habitats.

What are the two major groups of dinosaurs?

Ornithischians (herbivores) and Saurischians (including theropods).

What adaptations allow birds to fly?

Feathers, hollow bones, and efficient lungs.

What group is known for having a complex placenta?

Eutherians, or placental mammals.

What evolutionary trend can be observed in the skeleton of vertebrates?

The evolution from cartilage to mineralized bone to an internal bony skeleton.

What feature do lancelets retain as adults?

all chordate traits

What are the four membranes of the amniotic egg?

Amnion, chorion, yolk sac, and allantois.

What is the primary feeding strategy of tunicates as adults?

sessile and filter feeders.

What do all vertebrates have that is unique during embryonic development?

Neural crest cells.

What do we call jawed vertebrates?

Gnathostomes.

What was the major extinction event for non-avian dinosaurs?

Non-avian dinosaurs went extinct 66 million years ago.

How do amphibians undergo gas exchange?

through their skin.