Chordata Subphylum Urochordata Quiz

Questions and Answers

What does Urochordata mean?

Free-living larva

Colonial forms

Tail backstring (correct)

Sea squirts

Recent discovery of ________ in Urochordata, which makes it have a closer common ancestor than Cephalochordata.

Neural crest cells

(Recent discovery of neural crest cells in Urochordata) _______ previously was thought to be unique to vertebrates.

Neural crest

(Recent discovery of neural crest cells in Urochordata) Neural crest cells emerge from a.)__ in Urochordates, similar to what happens in the b.).

a.) Neural tube, b.) Vertebrates Signup and view all the answers

(Recent discovery of neural crest cells in Urochordata) The neural crest cells migrate to a.)__ and form b.) (only derivatives known so far).

a.) Body wall, b.) Pigment cells Signup and view all the answers

(Recent discovery of neural crest cells in Urochordata) Presence of a.)___ & b.)_ now places c.) most closely related to d.)____.

a.) Neural crest, b.) Molecular evidence, c.) Urochordates, d.) Vertebrates Signup and view all the answers

What type of reproduction do colonial forms of Urochordata exhibit?

Asexual and sexual reproduction Signup and view all the answers

Larva are __a.), sexually b.) form, that is c.) distinct from the d.) stage, usually eats different food, and may even have e.) than adult.

a.) Free-living, b.) Immature, c.) Morphologically distinct, d.) Adult stage, e.) Different habitat Signup and view all the answers

What is the process called that transforms larva into adult Urochordates?

Metamorphosis Signup and view all the answers

In this stage, it only lasts a few hours to a few days at most.

As larvae ('ascidian tadpole') Signup and view all the answers

During the time of larval metamorphosis, they feed.

False Signup and view all the answers

Flexible outer body covering of acellular material (i.e. ECM) secreted by underlying epidermis is called ___.

Tunic (test) Signup and view all the answers

Some a.)__ structures contained in b.)_ at anterior end of c.).--> light sensitive d.)_ -> gravity sensitive e.)_

a.) Rudimentary sensory structures, b.) Sensory vesicle, c.) Nerve cord, d.) Ocellus, e.) Otolith Signup and view all the answers

What is the eye of Urochordate larvae called?

Ocellus Signup and view all the answers

What is the ear of Urochordate larvae called?

Otolith Signup and view all the answers

The rudimentary a.)__ function as _b.)

a.) Cerebral ganglion & Visceral ganglion, b.) Processing centers Signup and view all the answers

Metamorphosis attached to substrate by _______.

Adhesive papilla Signup and view all the answers

a.)__ are surrounding the notochord which separate from one another and the notochord goes limp due to b.).

a.) Epithelial notochord cells, b.) Loss of fluid Signup and view all the answers

The ___________ is drawn into the outer body and reabsorbed (loss of 3 of 5 chordate characteristics).

Axial complex (notochord, dorsal nerve cord, and tail muscles) Signup and view all the answers

What other structures are lost during metamorphosis?

Outer tunic layer, sensory vesicle and visceral ganglion Signup and view all the answers

a.) enlarges, number of Pharyngeal slits b.)_, and c.) begins.

a.) Pharynx, b.) Increases, c.) Active feeding Signup and view all the answers

a.)__ further subdivide into smaller openings called b.), resulting in a c.), known as a d.)_.

a.) Pharyngeal slits, b.) Stigmata, c.) Radically remodeled pharynx, d.) Branchial basket Signup and view all the answers

Also, note ___________ of metamorphosis.

Rotation of structures Signup and view all the answers

As adults, they show ONLY a.)_, which is homologous to the b.)_ of vertebrates.

a.) Large, elaborate filtering basket, b.) Gill slits and gill system Signup and view all the answers

List the criteria for adult's feeding.

1.) Elaborated pharyngeal apparatus, 2.) Unidirectional flow of water (in one opening, out another), 3.) Water drawn in by cilia through branchial (incurrent) siphon, 4.) Water flows into branchial basket and through stigmata (sieves), 5.) Mucus produced by endostyle lines basket and traps particles, 6.) Rows of cilia collect mucus and sweep it to the gut, 7.) Water then enters atrium, space between basket and tunic, 8.) Water exits via the atrial siphon Signup and view all the answers

Adult feeding has ___________ apparatus.

Elaborated pharyngeal Signup and view all the answers

Adult Urochordates have unidirectional flow of water.

True Signup and view all the answers

Water drawn in by a.)_ through b.)_.

a.) Cilia, b.) Branchial (incurrent) siphon Signup and view all the answers

Water flows into a.)__ and through b.).

a.) Branchial basket, b.) Stigmata (sieves) Signup and view all the answers

a.) is produced by endostyles, which lines the b.) and c.).

a.) Mucus, b.) Basket, c.) Traps particles Signup and view all the answers

Rows of a.) collect mucus, and sweep it to the b.).

a.) Cilia, b.) Gut Signup and view all the answers

Water enters the a.)_, which is the space between the basket and b.)___.

a.) Atrium, b.) Tunic Signup and view all the answers

Water exits via ___________.

Atrial siphon Signup and view all the answers

Note that the adult is specialized for _______________, and that's about it.

Feeding and reproduction Signup and view all the answers

They have a a.). There is a recent discovery of b.) and are c.) as adults.

a.) Tail, back string, b.) Neural crest, c.) Sessile Signup and view all the answers

Lacks a.). It has a b.), that they had and lost during c.).

a.) Notochord & DHNC, b.) Subpharyngeal organ & Pharyngeal slits, c.) Development Signup and view all the answers

They have a.)_ with b.) in between.

a.) Pharyngeal slits, b.) Bars Signup and view all the answers

The Endostyle is their __________.

Subpharyngeal organ Signup and view all the answers

They are a.)_ and they have a digestive system, which is their b.)__. They also have gonads.

a.) Sessile = attached to the bottom, b.) Gut Signup and view all the answers

As larvae, their tail is known as the a.)___ and they have b.)_ characteristics, but only have c.) as adults.

a.) Axial complex, b.) ALL 5 characteristics, c.) 2 characteristics Signup and view all the answers

Which stage are sessile and can go through both sexual and asexual reproduction?

Adults Signup and view all the answers

In Asexual reproduction, this is mushy.

Stolon Signup and view all the answers

During sexual reproduction, the offspring does a.)__, so they can get away from the family. This means they are b.). It can lasts hours, and/or days depending on c.).

a.) Dispersal, b.) Mobile, c.) What the organism is Signup and view all the answers

In figure 2.25, the organism loses the a.)_ and b.) it. Some can reproduce without c.); genetically the 2 are d.)__.

a.) Dorsal axial, b.) Reabsorbs, c.) Meiosis and reproduction, d.) Identical Signup and view all the answers

In the Ascidian tadpole (larvae) known as a.)__ have b.) have structures.

a.) 'Seasquirts', b.) Axial complex of notochord, DHNC, and segmented muscle Signup and view all the answers

These are the filtering baskets.

Branchial basket with pharyngeal slits Signup and view all the answers

a.) are the eyes, and b.) are for hearing and balance. The 2 together are for c.)___.

a.) Ocellus, b.) Otolith, c.) Sensory vesicle Signup and view all the answers

What is used for digestion in Urochordates?

Visceral digestion Signup and view all the answers

From the neck and up, all of the structures are a.), and are lost during b.).

a.) Reabsorbed and reused, b.) Metamorphosis Signup and view all the answers

Structures in the tail are __________.

Past the gut Signup and view all the answers

This was originally ventral and has signified slits.

Stigmata Signup and view all the answers

What has an outflow and is homologous to the atrial pore?

Excurrent (atria) siphon Signup and view all the answers

In Figure 2.24, name the 3 elaborate structures.

1.) Pharynx, 2.) Branchial basket, 3.) Endostyle Signup and view all the answers

Figure 2.24 has NO post-anal tail.