Smart Book Connect - Echinoderms

Characteristics of sea daisies include

two concentric ring canals. either a velum or shallow, saclike stomach with no intestine. presence of a hydropore.

deep (hyponeural system)

A unit of the nervous system that lies aboral to the oral system

In sea stars, the area on the oral side of the organism that runs from the mouth to the tip of each arm is called the

Ambulacra

Crinoidea

Arms with open grooves for planktonic and suspension feeding

In echinoderms, the calcareous sieve-like structure that leads to the water vascular system is known as the

Madreporite

True or false: Echinoderms rarely inhabit brackish waters

True

Excretion and respiration in sea stars is facilitated by their spacious body__________, which is filled with fluid

coelom

Holothuroidea

sea cucumbers

Asteroidea

sea stars

Echinoidea

sea urchins, sand dollars, heart urchins

Because they are ineffective on soft substrates, many sand-dwelling sea stars don't have _________________on their tube feet

suckers

The members of what taxon have a flattened body composed of a central disc connected to tapering rays and is covered by a ciliated, often brightly colored epidermis?

Asteroidea

As it develops, a bipinnaria will grow three adhesive arms and a sucker at its anterior end

At this point, the sea star larva is called a ¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬_________ and it attaches to a substratum, where it undergoes metamorphosis. brachiolaria

Members of what phylum are characterized by having a spiny calcareous endoskeleton, pentaradial symmetry, and a water-vascular system?

Echinodermata

Sea stars, brittle stars, sea urchins, sea cucumbers, and sea lilies are all members of what phylum?

Echinodermata

In sea stars, the mouth connects to a stomach via a short

esophagus

Crinoidea

feather stars, sea lilies

A typical echinoid test is made of _____________

ten sets of plates, which have many movable, stiff spines

Sea stars can use their tube feet for locomotion by applying pressure to the liquid in the tube feet using various sets of muscles, Which of the following statements accurately describe those processes? Select all that apply

Contraction of longitudinal muscles in the tube foot retracts the podium. Contraction of muscles on one side of the tube foot causes the tube foot to bend toward that side. Contraction of muscles in the ampulla forces liquid into the podium of the tube foot, extending it.

Which of the following best characterize irregular echinoids?

Short spines Secondarily bilateral

Select all of the following that describe members of class Echinoidea

The body is enclosed within a test comprised of closely fitting ossicles. Some species are secondarily bilateral with short spines. They are found in a wide diversity of marine habitats, from intertidal areas to deep oceans.

Echinoderms have a unique set of hydraulic canals, tube feet, and dermal ossicles that collectively form the_________________ _________________system

Water vascular

On the aboral surface, the pincerlike structures that occur around the bases of echinoderm spines and that function in keeping the body clean, protecting papulae, and capturing food are called

pedicellariae

Select all of the external features of the echinoderm class Asteroidea

A flattened body with five or more tapered rays emanating from a central disc, Open ambulacral grooves, each lined by tube feet, Papulae for respiration

How do sea stars exchange gases with the outside and excrete their wastes?

Both gases and wastes can leave the body by diffusion through papulae and tube feet.

oral (ectoneural) system

Comprised of a nerve ring around the mouth and a main radial nerve in each arm; coordinates the podia

aboral system

Comprised of a ring around the anus and radial nerves along the roof of each arm

epidermal nerve plexus

Connects the other components of the nervous system to the body wall and related structures

Holothuroidea

Elongated oral-aboral axis; reduced ossicles

Select all of the functions of the water vascular system in sea stars

Gathering food, Respiration, Excretion, Locomotion

Echinoderms can be found living under what conditions?

Great ocean depths, Intertidal zones

Echinoderms that have an elongated, cylindrical body with reduced ossicles and a leathery body wall are members of what class?

Holothuroidea

Select all true statements about the hemal system of sea stars

It includes an axial complex for filtering blood vascular fluids. It is found within the perihemal channels. It is comprised of a system of tissue strands that enclose unlined sinuses.

Which of the following are true of catch collagen?

It is able to quickly change from a more liquid to a more solid form. It is under the control of the nervous system. It allows an animal to hold a particular position without the use of its muscles.

Select all of the following that are true of the madreporite of sea stars

It leads to the water vascular system. It is circular in shape. It is found on the body's exterior.

Select all of the following that describe the water vascular system

It often plays an important role in locomotion. It is only found in echinoderms. It includes the tube feet. It opens to the outside through pores in the madreporite.

While they typically have five arms, brittle stars have a distinct morphology that is very different from that of sea stars (Asteroidea) Select all of the following that are characteristic of brittle stars

Lack of papulae and pedicellariae Tube feet without suckers Ambulacral grooves closed and covered by ossicles

Ophiuroidea

Most active echinoderms; jointed muscular arms used for locomotion

The endoskeleton of sea stars is comprised of calcareous plates called______________, which are connected to one another by a specialized connective tissue made of an unusual mutable collagen called _____________collagen

Ossicles, catch

Echinoidea

Radially symmetrical; compact skeleton with closely fitting plates

Select all of the following that are members of phylum Echinodermata

Sea cucumbers, Sea lilies, Sea urchins, Brittle stars

Sea stars can easily move up vertical surfaces, How do they generate the necessary suction force in their tube feet?

Small muscles lift the middle of the foot's disk-like end, which produces a suction force when the foot is applied to a hard surface.

What organ system of echinoderms plays a role in distributing digested nutrients throughout the body and includes the axial complex for pressure-filtering blood vascular fluids?

The hemal system

What is stereom in echinoderms?

The meshwork of spaces found in echinoderm ossicles that usually contains fibers and dermal cells.

Select all of the following that are true of the digestive system of sea stars

The stomach can be everted through the mouth to facilitate prey capture. The stomach is comprised of two parts.

Which of the following are true of reproduction in sea stars?

They are capable of both sexual and asexual reproduction. Gonads occur in pairs in each interradial space. Most species have separate sexes.

Choose all functions of pedicellariae in echinoids

They can have venom glands and inject toxins into small prey. They keep the body clean. They prevent marine larvae from settling on the body.

Select all of the characteristics of members of phylum Echinodermata

They possess a calcareous endoskeleton composed of plates or ossicles. They exhibit pentaradial symmetry. They possess a water-vascular system. They exhibit external spines and pedicellariae.

Asteroidea

Tube feet with suckers; many are star-shaped; 5 arms broadly connected to central disc

Do echinoids have tube feet, and if so, where are they located?

Yes, tube feet extend through pores in the five rows of ambulacral plates.

The hemal system of a sea cucumber is _______

better developed than that of a sea urchin

Ophiuroidea

brittle stars, basket stars

Echinoderms have a unique kind of connective tissue called_____________collagen that is under neurological control, allowing it to change quickly from a looser, more liquid form to a solid form

catch

Functions of pedicellariae include

cleaning the body. protecting the papulae.

The endoskeleton of sea stars and other echinoderms is comprised predominantly of

ossicles.

What structures are found within or bordering the ambulacral groove of sea stars? Select all that apply

tube feet, a radial nerve, spines