Biosciences Chapter 34 Part 1: Deuterostomes

What are the major groups of bony fish?

Dipnoi Actinistia Actinopterygii

Organisms with spiny skin that exhibit pentaradial symmetry as adults, and have an endoskeleton made of calcium carbonate plates, are known as the

Echinoderms Echinodermata

The organism shown in this photograph is a member of the class ______.

Echinoidea

What best describes symmetry in echinoderms?

Free-swimming larvae have bilateral symmetry, while the adult form is pentaradially symmetrical

Which fish may have vertebrae only as larvae?

Hagfish

What are the four features that characterize all chordates?

Presence of a single, hollow nerve cord Presence of a notochord during embryonic development Presence of pharyngeal slits or pouches in the embryo Presence of a postanal tail

What organisms are in the class Ophiuroidea?

brittle stars

The endoskeletons of echinoderms and chordates are

different in terms of function.

The vascularization of fish gills is

extensive.

The echinoderm shown in this photograph belongs to which class?

Ophiuroidea

The chordate subphyla are Urochordata, Cephalochordata, and

vertebrata

In echinoderms, the hydraulic system that aids in movement and feeding is called the ______.

water-vascular system

A fish heart contains how many chambers?

2

Amniotes appeared approximately ______ million years ago.

300

Most fish have ______ fins.

4

Vertebrate evolution is believed to have begun

545 mya.

What characteristics are found in vertebrates, but not tunicates or lancelets?

A distinct head Vertebrae

What are the characteristics of echinoderms?

Adults have pentaradial symmetry Endoskeleton made of calcium carbonate plates Deuterostome development

In terms of the functionality of the endoskeleton, to which group are echinoderms most similar?

Arthropods

Sea daisies belong to the class

Asteroidea

The class ______ includes the sea daisies.

Asteroidea

The echinoderm shown in this photograph is a member of which class?

Asteroidea

Match organisms to their class.

Asteroidea - Sea stars Holothuroidea - Sea cucumbers Echinoidea - Sea urchins Ophiuroidea - Brittle stars

_____ fishes evolved at the same time as sharks, some 400 million years ago.

Blank 1: Bony

Vertebrate evolution is thought to have begun in the _____ period.

Blank 1: Cambrian

Lancelets, which are members of the subphylum _____, are small, marine chordates.

Blank 1: Cephalochordata

_____ have chordate larval forms, which metamorphose into sessile, filter-feeding adults that bear little resemblance to other chordates.

Blank 1: Tunicates, Urochordates, or Urochordata

In echinoderms, the larvae are _____ symmetrical, and the adults are _____ symmetrical.

Blank 1: bilaterally Blank 2: pentaradially

This animal is called a _____ star because its arms can be easily autotomized.

Blank 1: brittle

Fish may have vertebrae that are composed of bone or _____.

Blank 1: cartilage

The postanal tail in human embryos regresses forming the tailbone which is also known as the _____.

Blank 1: coccyx

Fish gills consist of fine _____.

Blank 1: filaments

Sharks became dominant during the Carboniferous period due to a combination of several features. Sharks evolved an improved _____ structure, in which the upper part of the first gill arch became a reinforcing strut. Likewise, the _____ skeleton of sharks was reinforced to make it both light and strong.

Blank 1: jaw Blank 2: cartilaginous or cartilage

The five defining features of fish include the gills, fins, circulatory system, nutritional deficiencies, and _____.

Blank 1: jaws

Cephalochordates, or _____, are small marine chordates.

Blank 1: lancelets

Water enters the water-vascular system of echinoderms through a _____, a sieve-like plate.

Blank 1: madreporite

In vertebrates, a single, hollow _____ _____ differentiates into the brain and spinal cord.

Blank 1: nerve Blank 2: cord

In asteroids gas exchange occurs from protrusions of their epidermis called

Blank 1: papulae

The major groups of bony fish are the _____-finned fishes, the _____ fishes, and the _____.

Blank 1: ray Blank 2: lung Blank 3: coelacanths

Bony fish have a bony _____ and a skin covered in plates or _____.

Blank 1: skeleton or endoskeleton Blank 2: scales

The _____ of Chondrichthyans is made of cartilage, as opposed to bone.

Blank 1: skeleton, internal skeleton, or endoskeleton

The shark jaw was much improved over the more primitive jaw of spiny fishes, with the upper jaw fused to the _____, which in turn was hinged to the shoulder.

Blank 1: skull

Bony fish can effortlessly remain suspended at a particular depth in the water because of their _____ _____.

Blank 1: swim Blank 2: bladder

Gas exchange in most echinoderms occurs through the surface of their bodies and their _____ _____.

Blank 1: tube Blank 2: feet

Despite how different their sessile, filter-feeding adult forms seem, larval _____ clearly display chordate features.

Blank 1: tunicates or urochordates

The notochord in the human embryo is replaced by the _____ _____.

Blank 1: vertebral Blank 2: column

What are features of bony fishes?

Bony skeleton Scale-covered skin

Sharks, as well as skates and rays, have a cartilaginous skeleton. Which of the following correctly describes how this skeleton is "calcified"?

By integrating granules of calcium carbonate into the outer layers of cartilage

What is the chemical composition of the endoskeleton of echinoderms?

CaCO3

The skeleton of Chondrichthyans is made of which of the following?

Cartilage

Members of this phylum are characterized by a dorsal, hollow nerve cord, a notochord, pharyngeal gill slits, and a postanal tail.

Chordata

What are the key (defining) features of jawed fishes?

Internal gills Paired appendages A vertebral column Single-loop circulation Nutritional deficiencies

Choose all features typical of most bony fishes.

Internal skeleton made of bone Highly mobile fins

Why is the shark jaw considered to be much improved over the more primitive jaw of spiny fishes?

It was fused to the skull.

Which echinoderms has ossicles that form a rigid shell?

Sand dollars Sea urchins

Which of the following evolved in the early Devonian period (400 mya)?

Sharks Bony fishes

Identify the type of blood circulation that is found in fish.

Single-loop

Which features enabled the dominance of sharks during the Carboniferous period?

Streamlined paired fins A modification of the gill arches that reinforced the lower jaw Granules of calcium carbonate in the cartilaginous skeleton

When did sharks and bony fish first evolve?

The early Devonian (400 mya)

Describe shark teeth.

The teeth are not firmly anchored and are easily lost. The teeth have evolved from rough scales on the skin.

Which of the following accurately describes the purpose of calcium carbonate deposits in the outer layers of a shark's skeleton?

They "calcify" its cartilaginous skeleton

Which characteristics are absent in tunicates and lancelets but are present in vertebrates?

Three pairs of well developed sensory organs Enclosed dorsal nerve cord Brain encased in skull

Describe crinoid tube feet.

Tube feet arise from branches of the arms.

The nonvertebrate chordate subphyla are _____ and _____.

Urochordata Cephalochordata

At the base of each tube foot in most echinoderms there is a muscular sac called the

ampulla

The fins of lobe-finned fish differ from other fish because the fins of lobe-finned fish are

jointed.

Asteroids and echinoids use their tube feed for ______, while sea cucumbers, crinoids, and brittle stars use their tube feet for ______.

movement, feeding

What is a single, hollow structure that runs just beneath the dorsal surface of chordates, and which differentiates into the brain and spinal cord in vertebrates?

nerve cord

The two major clades of amniotes are the _____ and the _____.

synapsids diapsids

Shark teeth have evolved from rough _____ on the skin of a shark.

scales