Chapter 44

Question 1

The majority of all known animal species are:

Answer 1

insects

Question 2

Cnidarians have _____ symmetry

Answer 2

radal

Question 3

Ecdysozoans include insects and make up more than half of all known animal species.

Answer 3

true

Question 4

Which of the following statements is false regarding chondrichthyes?

Answer 4

Chondrichthyes can (typically) only tolerate low levels of urea.

Question 5

A phylogenetic tree is:

Answer 5

a diagram of the evolutionary relationships among different species.

Question 6

Which of the following is not true of sponges?

Answer 6

Sponges are among the most primitive organisms to have developed reproductive organs.

Question 7

The group Lophotrochozoa includes

Answer 7

annelid worms and mollusks.

Question 8

Which of the following are cartilaginous fish?

Answer 8

sharks and rays

Question 9

The period of time during which an “explosion” of fossilized animals with bilateral symmetry are first found is the

Answer 9

Cambrian.

Question 10

The development of wings on a fly, a moth, and a bird are ____ because they developed independently as adaptations to perform the common function of flying.

Answer 10

analogous

Question 11

Placozoans, which were first discovered in an aquarium, are by far the most diverse of the eumetazoans, with approximately 10,000 documented species.

Answer 11

false

Question 12

Imagine that scientists have discovered annelid life on a new planet. Remarkably, these worms are large in size, lack mouths, and appear to form symbioses with certain bacterial species. These worms most resemble ______________ on Earth.

Answer 12

vestimentiferan worms

Question 13

All amniotes lay eggs, as exemplified by reptiles, birds, and monotremes.

Answer 13

false

Question 14

The colonization of land by animals

Answer 14

may have taken place independently by a variety of species descended from aquatic environments.

Question 15

A protostome is distinguished by a(n):

Answer 15

blastopore that becomes a mouth.

Question 16

A researcher has just discovered a new marine organism that appears very similar to jellyfish. However, on closer inspection, this organism possesses both a mouth and anal pore, and a single set of tentacles. This animal is most likely a

Answer 16

comb-jelly.

Question 17

All echinoderms (sea stars and sea urchins) have:

Answer 17

a water vascular system and five-fold symmetry.

Question 18

Which of the following is not a characteristic of vertebrates?

Answer 18

an open circulatory system

Question 19

Which of the following is not true regarding the history of life on Earth?

Answer 19

The rise of more complex organisms such as eukaryotes has resulted in a reduction in diversity of more “primitive” organisms such as bacteria.

Question 20

Bilaterians are distinguished by:

Answer 20

mirror symmetry that results in a distinct head and tail and one plane of symmetry.

Question 21

Which of the following are cnidarians?

Answer 21

jellyfish and sea anemones

Question 22

Which of the following statements is true of chelicerates?

Answer 22

Chelicerates, unlike insects and crustaceans, do not actually have antennae.

Question 23

Vertebrates may have an external skeletal system.

Answer 23

false

Question 24

Unique characters evolve over long periods of time. The time that a particular character arose can be estimated by determining

Answer 24

shared presence of the character in descendants of the population in which the character first arose.

Question 25

A researcher has just discovered a new marine organism that appears very similar to jellyfish. However, on closer inspection, this organism possesses both a mouth and anal pore, and a single set of tentacles. This animal is most likely a

Answer 25

comb-jelly.

Question 26

Crustaceans:

Answer 26

have a hard external skeleton composed of a polysaccharide commonly known as chitin.

Question 27

Which of the following is true regarding hagfish and lampreys?

Answer 27

They are vertebrates

Question 28

Modern day birds are most closely related to which of the following?

Answer 28

dinosaurs

Question 29

(Please choose from the lettered responses below.) Phylogenetic trees help us understand:
1-the genetic relationships among a species.
2- the evolutionary relationships among a species.
3- the relationships of symmetry among related species.
4- the level of complexity among related species.

Answer 29

2 and 4

Question 30

A researcher is culturing cells in a petri dish. After a few weeks, she notices that these cells have formed a “sheet,” with junctions visible between individual cells. Which of the following statements is not true regarding these cultured cells?

Answer 30

These cells have formed mesoglea.

Question 31

Chordates include:

Answer 31

tunicates and vertebrates.

Question 32

If you have ever watched a television show on sharks, you may have noticed that certain fish attach themselves to sharks (and are considered to be parasites). Interestingly, these fish lack definitive jaws or mandibles. These parasitic fish are most likely:

Answer 32

lampreys.

Question 33

Microorganisms dominated Earth’s ecosystems for most of the planet’s history.

Answer 33

true

Question 34

_____ are not helpful for reconstructing evolutionary relationships because they do not show the evolutionary development of characters among groups.

Answer 34

Analogies

Question 35

What feature of animals enabled them to function in so many ways that they have been able to diversify in ways that plants, fungi, algae, and protozoans have not?

Answer 35

Organ systems

Question 36

What structure would you expect to find in every type of mollusk (i.e., gastropods, cephalopods, and bivalves)?

Answer 36

mantle

Question 37

Which of the following is not a cell or structure found in sponges?

Answer 37

gastric cavity

Question 38

Which of the following is not a component of some sponge skeletons?

Answer 38

cartilage

Question 39

A deuterostome is distinguished by a(n):

Answer 39

blastopore that becomes an anus.

Question 40

Which of the following statements is true of sponges?

Answer 40

External fertilization occurs in all species of sponge; sponge eggs are fertilized externally in seawater.

Like cnidarians, many sponges produce toxin-generating nematocysts. These cells typically line the pores of sponges.

The choanocytes of sponges and choanoflagellates share no morphological similarities.

Like comb-jellies, sponges possess both a mouth and an anal pore; however, the anal pore is distinctly smaller than the mouth.

None of these statements are true regarding sponges.

Question 41

Regarding the gastric cavity of the cnidarians, which of the following is true?

Answer 41

Digestive enzymes allow the consumption of prey such as fish whole.

Question 42

Ctenopores (comb jellies):

Answer 42

have a separate mouth and anal pore, unlike cnidarians.

Question 43

If you’ve ever read any stories about Sherlock Holmes, you may remember that he once solved a mystery where a man died due to injuries sustained from a lion’s mane jellyfish. Apparently, the victim encountered this free-floating jellyfish in a pool of water, was stung, and died suddenly. From this information, you can deduce that the victim encountered the jellyfish in what form?

Answer 43

medusa

Question 44

All lophotrochozoa have:

Answer 44

bilateral symmetry and complex organs.

Question 45

Triploblastic organisms give rise to ___ germ layers, which include _______.

Answer 45

three; ectoderm, mesoderm, and endoderm

Question 46

Which of the following is not true of sponges?

Answer 46

Sponges are among the most primitive organisms to have developed reproductive organs.

Question 47

____ are helpful for reconstructing evolutionary relationships because they show the evolutionary development of characters among groups.

Answer 47

Homologies

Question 48

Due to the production of chitin, arthropods occupy a unique position on the tree of life. These organisms are much more closely related to fungi (which also produce chitin) compared to either cnidarians or lophotrochozoans.

Answer 48

false

Question 49

Which of the following is false regarding cnidarians?

Answer 49

Cnidarians have a separate opening for the anus and the mouth.

Question 50

What feature of animals enabled them to function in so many ways that they have been able to diversify in ways that plants, fungi, algae, and protozoans have not?

Answer 50

Organ systems

Question 51

Insects:

Answer 51

have a respiratory system including spiracles connecting to a trachea.

Question 52

Linnaeus sorted animals into groups based on body plans. Today, these groupings are called:

Answer 52

phyla.