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