4.3

Question 1

What are the two lineages in the bilaterian clade?

Answer 1

Protostomes and deuterostomes

Question 2

Where did all the protostomes come from?

Answer 2

A common ancestor that diverged away from the deuterostome group, through genomic data

Question 3

What are most animals?

Answer 3

protostomes

Question 4

Which phyla make up most of the animals?

Answer 4

Phylum Arthropoda

Question 5

Which group makes up most of the arthropoda?

Answer 5

insects

Question 6

Where can protostomes be found?

Answer 6

in most habitats

Question 7

How many protostome lineages adapted to living on land?

Answer 7

Several

Question 8

Which lineages adapted to living on land in deuterostomes?

Answer 8

Chordates

Question 9

Protostome benefits to living on land?

Answer 9

New resources and safety from predators

Question 10

Protostome challenges to living on land?

Answer 10

Desiccation, gas exchange, support against gravity, getting sperm to egg, protecting embryo. Explain

Question 11

How did protostomes prevent desiccation?

Answer 11

Developed waterproof skin or stayed in moist environments

Question 12

How did protostomes prevent gas exchange?

Answer 12

used their skin for gas exchange or developed internally respiratory structure with openings that could open and close

Question 13

How did protostomes have support against gravity?

Answer 13

used their coelom as a hydrostatic skeleton and stayed small. Arthropods developed exoskeleton

Question 14

How did protostomes get the sperm to the egg?

Answer 14

internal fertilization

Question 15

How did protostomes protect embryos?

Answer 15

eggs with desiccation resistant coverings (no food)

Question 16

What two classes make up protostomes?

Answer 16

Lophotrochozoa and Ecdysozoa

Question 17

What are three unique characteristic of lophotrochozoans?

Answer 17

lophophore, trochophore larva, spiral cleavage

Question 18

What is the lophophore?

Answer 18

a circular ridge around the mouth with ciliated hollow tentacles, is unique to three filter-feeding lophotrochozoan phyla

Question 19

What is a trochophore larva stage?

Answer 19

A common stage in many aquatic lophos

Question 20

Where is spiral cleavage?

Answer 20

Derived trait in lophos but lost in rotifera

Question 21

How many major phyla are in lopho?

Answer 21

17

Question 22

What is the most diverse lophotrochozoan?

Answer 22

mollusk phylum

Question 23

What are phylum platyhelminthes?

Answer 23

flatworms

Question 24

Flatworm characteristics?

Answer 24

Acoelomate (coelom was lost)
GVS
excretory system
reproductive system
centralized nervous system

Question 25

What are the three classes of flatworms?

Answer 25

Turbellariians, cestoda, trematoda

Question 26

Define turbellarians

Answer 26

free-living - terrestrial or aquatic

Question 27

Define cestoda

Answer 27

tapeworms – intestinal parasites

Question 28

Define trematoda

Answer 28

flukes – blood vessel parasites

Question 29

What is the life cycle of flukes

Answer 29

*Eggs get into water and larvae
infect intermediate host (snails)
*Final larval stage bursts out of
snails and burrows into
definitive host (birds or
mammals) to mature in a blood
vessel.

Question 30

What is the life cycle of tapeworms

Answer 30

*Eggs are eaten and larvae live in
muscles of intermediate host
*Uncooked muscle is eaten and
larvae mature into adults in
intestines of the definitive host

Question 31

What are phylum annelida

Answer 31

segmented worms

Question 32

Characteristics of segmented worms

Answer 32

*segmented body
*parapodia
*chaetae (bristles)
*True coelom
*Complete gut
*All the organ systems that
flatworms have, plus:
–Closed circulatory system
(blood stays inside of vessels)
–Some have respiratory
structures (gills)

Question 33

What are annelid synapomorphies

Answer 33

Segmentation, parapodia, chaetae

Question 34

Three main groups of annelids?

Answer 34

polychaetes, oligochaetes, hirudinea

Question 35

polychaetes

Answer 35

all marine; diverse feeding styles

Question 36

oligochaetes

Answer 36

aquatic or
terrestrial; all
deposit feeders;
includes
earthworms

Question 37

hirudinea

Answer 37

only some are
parasites,
others are
predators or
scavengers

Question 38

How are annelids and platyhelminthes different?

Answer 38

p lost coelom a has a true coelom. p is flat a is segmented. p has gvc a has complete gut. P doesnt have circulatory system a does. a have chaetae and parapodia, p does not

Question 39

How are annelids and platyhelminthes similar?

Answer 39

Both have excretory and reproductive systems and nervous systems. Both bilaterally symmetrical. organ grade. invertebrates

Question 40

phylum Mollusca characteristics

Answer 40

True coelom – but reduced to around the heart (why?)
Unsegmented bodies
*Have all the organ systems
that annelids have.
*All except cephalopods have
an open circulatory system
(blood leaves blood vessels
and seeps through tissues)
*Muscular foot
*Visceral mass
*Mantle
*Radula

Question 41

Muscular foot

Answer 41

a large muscle used for locomotion.

Question 42

Mantle

Answer 42

a flap of skin that covers the visceral mass and
forms an enclosed space into which the gills project. It
may or may not secrete a shell

Question 43

Visceral mass

Answer 43

a solid mass containing most of the
internal organs

Question 44

Chitons and gastropods use a _____for feeding

Answer 44

radula

Question 45

Cephalopods

Answer 45

Cephalopods have a
hard beak in addition to
a radula to tear apart
prey. They are often
associated with venom