Principles of Zoology Chapter 15 Review Exam 3

Which group is so specialized that they are only found on the mouth parts of marine decapods in the northern hemisphere?

Cycliophorans

Phoronid worms

are tube-dwelling marine animals.

Which is NOT a correct description of the function of the phoronid lophophore?

All of the choices are correct.

The digestive system of a phoronid worm has

cilia in the stomach area of the U-shaped gut.

The phoronid circulatory system

is a closed system but lacks a heart.

Reproduction and development in phoronid worms involves

all of the choices are correct

Why are entoprocts not included with the ectoprocts since they look nearly identical and were both called bryozoans in earlier times?

Entoprocts are acoelomates and lack sexual reproduction

The __________ is the secreted body wall of an ectoproct, together with its secreted exoskeleton.

cystid

The __________ includes the lophophore, digestive tract, muscles, and nerve centers.

polypide

How can you distinguish an ectoproct from a hydroid?

The hydroid lacks any complex digestive gut including any anus

The respiratory system of an ectoproct involves

no system at all, merely diffusion across the body surface.

Ectoproct colonies have modified zooids to

protect the colony and sweep away foreign particles.

Reproduction and development in ectoprocts involves

all choices are correct

The lophophore contains an extension of the

mesocoel

Statoblasts are usually formed

in freshwater ectoprocts

Brachiopoda

have a mantle and two valves (shells).

Entoprocts

have a crown of ciliated tentacles.

Ectoprocta live in

colonies and form protective masses.

The lophophorate phyla are grouped together because

they all possess a specialized crown of tentacles specialized for sedentary filter feeding.

The brachiopods live in

bivalved shells they secrete.

The lophophore is

all of the choices are correct

The coelom of a lophophorate is divided into

three parts: the protocoel, mesocoel, and metacoel.

The larval stages of all three lophophorate phyla are

free swimming

Lamp shells are not included in Mollusca because they

have a dorsal-ventral shell and gather food on tentacles.

The fossil record of brachiopods shows

they have existed nearly unchanged in design since the Ordovician times.

The pedicel of a brachiopod functions

as a stalk to attach it to the substrate.

Brachiopods reproduce and develop

all of the choices are correct

The valves of brachiopods are

All of the choice are Correct

*Secreated by the mantel

*Dorsal and Mantel

*Hinged in some with a tooth-and-socket arrangement.

Nemerteans differ from flatworms in that nemerteans possess

an eversible probsoscis.

Although they are trochozoans, molluscs and annelids are discussed separately from the brachiopods, nemerteans, and phoronidans. Explain why the molluscs and annelids separated in this discussion.

Molluscs and annelids have greater internal and external complexity compared to the rest of the trochozoan phyla.

If a cycliophoran population was very low in its unusual but favorable habitat, what type of larvae would you expect to be produced?

Pandora

Predict what would happen to a nemertean that lost its proboscis.

The nemertean would no longer be able to feed.

How does a closed circulatory system specifically benefit a nemertean?

It facilitates rapid hunting responses.