Question 1

Echinoderms are

Accepted Answer

A) mostly pelagic or free-swimming in open ocean. 
B) benthic. 
C) parasitic. 
D) mostly particle feeders. 
E) fish predators.

Question 2

Chaetognaths are also known as ______ ______.

Accepted Answer

The answer of Chaetognaths are also known as ______ ______....

Question 3

The ___________ ___________ was formerly thought to be a notochord.

Accepted Answer

The answer of The ___________ ___________ was formerly thought to...

Question 4

Ecologically,sea stars are at what trophic level?

Accepted Answer

A) Producer 
B) Herbivore 
C) Top carnivore 
D) Omnivore 
E) Detritivore

Question 5

Hemichordates do not have a kidney,but they do have a single _____________.

Accepted Answer

The answer of Hemichordates do not have a kidney,but they...

Question 6

Arrow worm reproduction and development involves

Accepted Answer

A) separate male and female individuals. 
B) a larval stage that lacks sense organs. 
C) a coelom but there is no peritoneum lining. 
D) spiral and unequal cleavage. 
E) a coelom formed from the archenteron extending backward,not from pinched off coelomic sacs.

Question 7

A system of unknown function consisting of tissue strands enclosing unlined channels is the __________ system.

Accepted Answer

The answer of A system of unknown function consisting of...

Question 8

The pores leading to both the protocoel and paired coelomic cavities of the enteropneust hemichordates allow

Accepted Answer

A) fertilization of eggs by sperm. 
B) exchange of fluids for a low efficiency respiratory system. 
C) water to be drawn in to stiffen the chambers to aid in burrowing. 
D) excretion of wastes. 
E) movement of ions and water to keep an osmotic balance.

Question 9

The mouth of the brittle star is surrounded by five movable plates that serve as ___________.

Accepted Answer

The answer of The mouth of the brittle star is...

Question 10

In echinoderms,the main coelomic compartment is

Accepted Answer

A) missing. 
B) a somatocoel. 
C) completely converted into the water-vascular system. 
D) the pyloric stomach. 
E) restricted to a small space around the gonads.

Question 11

If the radial nerve in an arm is cut,the podia in that arm lose coordination;if the circumoral nerve ring is cut,podia in all arms are uncoordinated and movement ceases.This indicates that

Accepted Answer

A) the hydraulic system is not involved in movement of tube feet. 
B) the radial nerve controls the nerve ring. 
C) part of the function of tube feet is hydraulic and part is controlled by the nerve stimulation. 
D) water pressure in the hydraulic system is directly controlled by the nervous system. 
E) the sea star is aware of the extent it is damaged and can change behaviors to compensate.

Question 12

The hemichordates and echinoderms apparently form a sister group to the ________________.

Accepted Answer

The answer of The hemichordates and echinoderms apparently form a...

Question 13

The nervous system of an enteropneust hemichordate (or acorn worm)consists of

Accepted Answer

A) a small brain and a dorsal ladder network of ganglia for each body segment. 
B) a network or plexus that runs underneath the epithelial cells that fuse to become ventral and dorsal neurochords. 
C) a small brain and a ventral ladder network of ganglia for each body segment. 
D) no brain but an extensive network of ganglia transferring information from sensory organs to the digestive system. 
E) no specialized nerves;the epetheliomusculature must respond to stimuli itself in a manner similar to the cnidarians.

Question 14

The water vascular system is derived embryologically from the left _______ ________ ________.

Accepted Answer

The answer of The water vascular system is derived embryologically...

Question 15

The respiratory tree of a sea cucumber is

Accepted Answer

A) not present in other echinoderms. 
B) branches off the cloaca of the animal. 
C) also serving in excretion. 
D) not a replacement for gas exchange through the skin and tube feet. 
E) All of the choices are correct.

Question 16

The designation of hemichordates as primitive chordates in 1885 by Bateson has proved

Accepted Answer

A) accurate using new molecular data. 
B) overenthusiastic since the structure he interpreted as a notochord does not have notochord embryology. 
C) completely wrong since new research indicates that all features he interpreted as chordate features are actually other structures. 
D) as puzzling today as in 1885. 
E) None of the choices is correct.

Question 17

________________ larvae of nonbrooding echinoids may live a planktonic existence for several months and then metamorphose into young urchins.

Accepted Answer

The answer of ________________ larvae of nonbrooding echinoids may live...

Question 18

The role of the hemal system is best described as

Accepted Answer

A) circulatory. 
B) excretory. 
C) an accessory gland to the reproductive system. 
D) a component of the nervous system. 
E) still not known for certain.

Question 19

How do the tube feet of sea stars and sea urchins operate?

Accepted Answer

A) Sticky threads lead back to the mouth and primitive brain 
B) Cilia transport hemolymph from chamber to chamber 
C) Actin and myosin in muscles in the five arms or "rays" constrict the tube feet directly when stimulated by nerves from the sea star brain 
D) A hydraulic system regulates water pressure in the tube feet 
E) Each tube foot is an independent organism and the sea star is a colonial mass

Question 20

Tube feet run along the ___________ groove that extends along the oral side from the mouth to the tip of each arm.

Accepted Answer

A) Ambulacral 
B) Hemal 
C) Radial 
D) Dermal 
E) Lateral

Exam 22: Chaetognaths, echinoderms, and Hemichordates