Exam #3 Study Guide Flashcards by Amber Barnhart

which phylum?
common shared features include unusual ribbon of teeth called radula, large muscular foot or tentacles for movement, and mantle for respiration and cell secretion

phylum ecdyzoans
phylum annelids
phylum mollusca
phylum nemotoda

phylum mollusca

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what kind of circulatory system to most cephalopods have?

closed

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this class of mollucs can use head and foot into the mantle cavity to create jet propulsion

class cephalopods
class gastropods
class caudofoveata
class solenogasters

class cephalopods

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this class of molluscs can withdraw head and food into the mantle cavity and hide into the shell

class cephalopods
class gastropods
class caudofoveata
class solenogasters

class gastropods

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are most molluscs dioecious or monoecious?

dioecious, some are hermaphroditic

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what kind of larva do molluscs have?

trocophore

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this kind of shell is from fossils and is one plane (flat) in molluscs?

planospiral shell
conspiral shell

planospiral shell

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what kind of shell is shifted over the body for better weight distribution in molluscs?

conspiral shell
planospiral shell

conspiral shell

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what kind of circulatory systems do most gastropods have?

open

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what kind of skeleton do most gastropods have?

mushy skeleton
boney skeleton
hydraulic skeleton
muscular skeleton

hydraulic skeleton

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this class in phylum mollusca has a single shell consisting of two hinged valves, an umbo, and a mantle used for jet propulsion

class gastropoda
class bivalvia
class cephalopoda

class bivalvia

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what kind of larval stage do bivalves have?

trocophore
locopohore
glochidia (parasitic)

glochidia (parasitic)

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the giant clam, rock scallop, and geoduck are all in the class:

class gastropoda
class bivalvia
class cephalopoda

class bivalvia

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the squid, octopuses, cuttlefish, and nautiluses are all in the class:

class gastropoda
class bivalvia
class cephalopoda

class cephalopoda

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the marine snails, limpets, slugs, whelks, conches, periwinkle, sea slugs, sea hares, and sea butterflies are all in the class:

class gastropoda
class bivalvia
class cephalopoda

class gastropoda

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this class of molluscs are known for a modified foot into a circle of tentacles or arms and a head in line with the visceral mass

class gastropoda
class bivalvia
class cephalopoda

class cephalopoda

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this class uses jet propulsion by using muscles of the mantle compressing water within the mantle cavity and siphon:

class gastropoda
class bivalvia
class cephalopoda

class cephalopoda

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what kind of circulatory system does class cephalopods have?

closed

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this class of molluscs uses spermatophores or packets of sperm to transfer to the female:

class gastropoda
class bivalvia
class cephalopoda

class cephalopoda

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this class of mollusc is sometimes seen using protandry in some monoecious species:

class gastropoda
class bivalvia
class cephalopoda

class gastropodaw

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which two classes of molluscs has a veliger larval stage?

class gastropoda
class bivalvia
class cephalopoda

class gastropoda
class bivalvia (also has spat)

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which phylum is known for a metameric body, sophisticated nervous system for fine motor control, and injury to part will not be fatal to the whole?

phylum ecdyzoans
phylum annelids
phylum mollusca
phylum nemotoda

phylum annelids

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this group of annelids are mobile, active worms often found in marine environments where they swim or burrow:

errantia
sedentaria

errantia

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this group of annelids are stationary, living in tubes or burrows where they engage in less movement:

errantia
sedentaria

sedentaria

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what is the sister group to the annelids? hirudinida clitellata sipuncula

sipuncula

what two classes are in clade clitellata and lack parapodia and are hermaphroditic? class oligochaeta class hiuridinea class clitellata class sipuncula

class oligochaeta class hiruidnea

this class includes earthworms: class oligochaeta class hiuridinea class clitellata class sipuncula

class oligochaeta

this class includes leeches: class oligochaeta class hiuridinea class clitellata class sipuncula

class hiruidnea

are those in class hiruidnea monoecious or dioecious?

monoecious, sexual reproduction on ly

this phylum is known for having a cuticle that can molt using ecdysis: phylum ecdyzoans phylum annelids phylum mollusca phylum nemotoda

phylum ecdyzoans

ecdyzoans can have different body plans (psudeocoelemate/ coelomate) t/f

true

which members of ecdyzoa are pseudococlomate? priapuldia nematoda nematomorpha kinohyncha

nematoda nematomorpha kinohyncha

which members of ecdyzoa are coelomate? priapuldia nematoda nematomorpha kinohyncha

priapuldia

this phylum has both dorsal and ventral nerves: phylum nematoda phylum nematomorpha phylum onychophora phylum tardigrada

phylum nemotoda

this phylum uses copulatory spicules to reproduce: phylum nematoda phylum nematomorpha phylum onychophora phylum tardigrada

phylum nemotoda

this phylum only has longitudinal muscles in the body wall: phylum nematoda phylum nematomorpha phylum onychophora phylum tardigrada

phylum nemotoda

ascaris lumbriocodes, nectra americanus, trichinella spiralis, and wuchereia spp, are all annelid parasites. t/f

false, they're nematode parasites

this phylum is known for free-living adult phase of life cycle achieves sexual maturity: phylum nematoda phylum nematomorpha phylum onychophora phylum tardigrada

phylum nematomorpha

this phylum is known for "velvet worms" and slime glands on each side of the body cavity open on oral papillae: phylum nematoda phylum nematomorpha phylum onychophora phylum tardigrada

phylum onychophora

what is tagmatization?

specialization of body regions

this phylum is known for very small organisms that can use cryptobiosis by dehydrating 82% to 3% of water: phylum nematoda phylum nematomorpha phylum onychophora phylum tardigrada

phylum tardigrada

what shape of muscles do annelids use to move?

circular: flattens longitudinal: expands

Respiration in most gastropods is performed by a ______. osphradium proboscis ctenidium radula

ctenidium

Molluss called ______ are mostly sedentary filter feeders and have two shells, no head, and no radula. bivalves cephalopods gastropods

bivalves

______ have the most elaborate nervous and sensory system of all of the molluscs. bivalves cephalopods gastropods

cephalopods

The head of an annelid is the first true segment. t/f

false

oligochaeteta hirudinida polychaetes match with the following: leeches marine worms earthworms

oligocaeteta: earthworms hirudinida: leeches polychaetes: marine worms

The end of the excretory organ that opens into a coelomic compartment in the polychaete body is the _______. nephrostome nephridiopore nephrocoel

nephrostome

Select all of the following that describe oligochaetes. They lack setae. Some are parasitic. Most are terrestrial or freshwater. Most live in marine habitats They lack parapodia.

Some are parasitic. Most are terrestrial or freshwater. They lack parapodia.

In most earthworms, each segment bears pairs of ______ which anchor the body during locomotion. radioles setae clitella parapodia

setae

What is the “brain” of an oligochaete? Pair of cerebral ganglia Ventral nerve cord Giant axons Nerve ring

Pair of cerebral ganglia

Leeches differ from other annelids in that they possess less specialization setae distinct coelomic compartments a fixed number of segments

a fixed number of segments

a ____ is a mucoid mass that extends to the stomach of gastropods and contains trapped food particles and is rotated by cilia style sac radula mantle cavity protostyle

protostyle

members of the class cephalopoda are the only molluscs that possess closed circulatory systems t/f

true

mollucs can be characterized by: -jointed appendages and radial symmetry -trocophore larvae and they are lophotrochozoans -a water vascular system and tube feet -segmented bodies and chitinous exoskeletons

trocophore larvae and they are lophotrocozoans

a clittellum is present in the members of the subclasses: polychaeta hirudinea and oligochaeta gastropoda and bivalvia cephalodpoda and scaphopoda

hirudinea and oligochaeta

the formation of a reproductive individual that differs from a non-reproductive individual is: parthenogenesis metamorphosis epitoky budding

epitoky

which of the following phyla are not pseudocoelomate? nematoda rotifera polychaeta nematomorpha

polychaeta

mictic eggs are diploid t/f

false

the _____ cells are specialized by excretory cells found in nematodes nephridia renette protonephridida renal

renette

members of the phylum nematomorpha are commonly called the ____ worms horsehair gordian ribbon both a and b

both a and b

what type of body cavity is found in annelids? acoelmate pseudocoelmate coelmate none of the above

coelomate

which of the following is a characteristic feature of oligochaetes? presence of parapodia well-developed head clitellum ability to swim

clitellum

the primary mode of locomotion in polychaetes is through the use of: cilia segmented muscles parapodia hydrostatic pressure

parapodia

which class of molluscs is characterized by a well-developed head and tentacles? bivalvia cephalopoda gastropoda polyplacophora

cephalopoda

in molluscs, the mantle is responsible for: protection and respiration circulation digestion nervous coordination

protection and respiration

which of the following organisms belongs to phylum nematoda? earthworm horsehair worm ascaris planaria

ascaris

the excretory system in nematodes primarily consists of: flame cells renette cells nephridia malpighian tubules

renette cells

the presence of a coelom in annelids allows for: greater flexibility in movement improved nutrient absorption development of complex organ systems all of the above

all of the above

which of the following statements about molluscs is true? they are exclusively marine animals all molluscs have a shell molluscs have a muscular foot for locomotion they lack a circulatory system

molluscs have a muscular foot for locomotion

the class polychaeta is distinguished by: presence of parapodia for locomotion lack of segmentation absence of chaetae (bristles) direct development without a larval stage

presence of parapodia for locomotion

in members of the class oligochaeta, the clitellum is primarily used for: sensory perception excretion reproduction respiration

reproduction

leeches (class hirudinea) differ from the other annelids in that they: lack setae (bristles) have a reduced coelum use suckers for locomotion and feeding all of the above

all of the above

gastropods exhibit torsion during development, which results in: coiling of the shell twisting of the body so that the anus is located near its head formation of the radula development of a siphon for filter feeding

twisting of the body so that the anus is located near its head

which of the following features is typical of class bivalvia? a radula used for feeding two hinged shells held together by adductor muscles a well-developed head with sensory organs jet propulsion as the primary mode of locomotion

two hinged shells held together by adductor muscles

members of the class cephalopoda differ from other molluscs by having: a closed circulatory system a muscular foot used for burrowing a mantle that secretes a calcareous shell a larval stage that undergoes torsion

a closed circulatory system

which of the following is a characteristic feature of nematodes? segmented body plan pseudocoelom true coelom external skeleton made of calcium carbonate

pseudocoelom

in the phylum nematomorpha, the adult stage is: free-living in aquatic environments parasitic in arthropods capable of asexual reproduction non-parasitic and terrestrial

free-living in aquatic environments

which of the following statements about tardigrades is true? they are pseudocoelomates like nematodes they undergo cryptobiosis to survive extreme conditions they are primarily parasitic on vertebrates they have jointed appendages and an exoskeleton

they undergo cryptobiosis to survive extreme conditions

Polychaetes are primarily terrestrial annelids that lack parapodia. T/F

False (Polychaetes are mostly marine and have parapodia for locomotion.)

Leeches (class Hirudinea) have segmented bodies but lack setae (bristles). T/F

True (Leeches are segmented annelids but do not have setae like other annelids.)

All molluscs have a radula for feeding. T/F

False (Bivalves do not have a radula, while most other molluscs do.)

Cephalopods possess a closed circulatory system, unlike most other molluscs. T/F

True Cephalopods possess a closed circulatory system, unlike most other molluscs.

Nematodes (roundworms) are coelomates, meaning they have a body cavity completely lined with mesoderm. T/F

False (Nematodes are pseudocoelomates, not coelomates.)

Which of the following statements correctly compares the circulatory systems of annelids and molluscs? a.) Annelids possess an open circulatory system, while molluscs have a closed circulatory system. b.) Both annelids and molluscs have open circulatory systems. c.) Annelids have a closed circulatory system, while molluscs have an open circulatory system. d.) Both annelids and molluscs have closed circulatory systems.

c.) Annelids have a closed circulatory system, while molluscs have an open circulatory system.

In which of the following ways do polychaetes differ from oligochaetes? a.) Polychaetes typically have fewer setae than oligochaetes. b.) Polychaetes usually exhibit a segmented body with parapodia, while oligochaetes do not. c.) Polychaetes are exclusively freshwater species. d.) Oligochaetes lack a clitellum, while polychaetes possess one.

b.) Polychaetes usually exhibit a segmented body with parapodia, while oligochaetes do not.

Annelids and nematodes are both classified as protostomes, indicating they share a more recent common ancestor than with deuterostomes. T/F

True

Which of the following groups is considered a sister group to molluscs based on phylogenetic relationships? a.) Arthropods b.) Annelids c.) Echinoderms d.) Nematodes

b.) Annelids

During development, which larval stage is typically observed in both annelids and molluscs? a.) Planula b.) Trochophore c.) Veliger d.) Zygote

b.) Trochophore

Nematodes undergo direct development, meaning they do not have a larval stage. T/F

True

Which of the following describes the developmental process unique to gastropods? a.) Metamorphosis b.) Torsion c.) Parthenogenesis d.) Schizocoely

b.) Torsion

Which of the following is a distinguishing feature of bivalves compared to other molluscs? a.) Presence of a radula b.) Body divided into three main parts: head, foot, and visceral mass c.) Two-part shell (valves) and filter-feeding mechanism d.) Ability to change color for camouflage

c.) Two-part shell (valves) and filter-feeding mechanism

How do the body plans of nematodes and annelids differ? a.) Nematodes have a segmented body; annelids do not. b.) Annelids have a pseudocoelom; nematodes have a true coelom. c.) Nematodes have a non-segmented body plan; annelids are segmented. d.) Both have identical body plans.

c.) Nematodes have a non-segmented body plan; annelids are segmented.

Molluscs and annelids share a more recent common ancestor with arthropods than with echinoderms T/F

True

Which of the following phyla is most closely related to annelids based on molecular phylogenetic studies? a.) Mollusca b.) Arthropoda c.) Onychophora d.) Nematoda

c.) Onychophora

Which developmental feature is unique to the life cycle of polychaetes? a.) Formation of a trochophore larva b.) Metamorphosis into a juvenile c.) Direct development without a larval stage d.) Torsion of the body

a.) Formation of a trochophore larva

The process of ecdysis is primarily associated with the development of annelids. T/F

False

Which stage in the life cycle of molluscs follows the trochophore larva? a.) Veliger larva b.) Adult c.) Egg d.) Planula

a.) Veliger larva

all of the following are unique to the molluscs except one. select the exception mantle shell visceral mass head-foot

shell

______ is developmental process that occurs in gastropods and results in a 180 degree counterclockwise twisting of the visceral mass and mantle cavity. gastrulation epiboly involution torsion

torsion

a ______ is rotated by cillia and extends into the stomach of bivalves. it produces a mucoid mass containing trapped food particles. protostyle umbo crystalline style gastric shield

crystalline style

which type of cephalopod possesses an external shell? cuttlefish nautilus squid octopus

nautilus

which of the following is generally accepted as the prevailing explanation behind the evolution of intelligence in cephalopods? their complex social structure the fact that they typically live long lives living as active predators as well as actively avoiding predators the pressures exerted by living in both marine and freshwater environments

living as active predators as well as actively avoiding predators

aquatic molluscs excrete _____, whereas terrestrial molluscs secrete ______. uric acid; ammonia ammonia; uric acid ammonia; oxygen oxygen; ammonia

ammonia; uric acid

members of the class cephalopoda and gastropoda are the only mollucs that possess a closed circulatory system. t/f

false; only cephalopoda

nuchal organs are chemoreceptors found in the head of a polychaeta worm t/f

true

an ocean dwelling worm in the errantia group (Nerius) would have a clitellum. t/f

false, errantia is outside of clitellada

the main propulsive structure(s) in the circulatory system of an earthworm is (are) capillaries dorsal and ventral aorta seminal vesicles the typhlosole

dorsal and ventral aorta

the specialization of body regions in segmented animals is called: tagmatization metamerism cephilization eutely

tagmatization

a distinctive feature of members of the subclass hirudinea is: parapodia anterior and posterior suckers tentacles palps

anterior and posterior suckers

pearl formation may occur in bivalves when an irritant becomes lodged between the shell and the mantle. the mantle secretes nacre around the irritant, gradually forming a pearl. t/f

true

A nonliving external layer secreted by the epidermis of many protostomes is called a ectoderm mesoderm cuticle ecdysis

cuticle

the most common worm parasite in the United States is the intestinal roundworm pinworm whipworm tapeworm

pinworm

The members of Phylum ______ are caterpillar-like in appearance, range 0.5 to 15cm in length, and inhabit tropical and subtropical regions. priapuldia onychopora kinorhyncha loricifera

onychopora

Which of the following is a characteristic of oligochaetes but not polychaetes? a.) Presence of parapodia b.) Trochophore larva c.) Clitellum for reproduction d.) Segmentation

c.) Clitellum for reproduction

Which type of feeding mechanism is most commonly found in bivalve molluscs? a.) Radula scraping b.) Suspension feeding c.) Predation using beak-like structures d.) Absorbing nutrients through the skin

b.) Suspension feeding

In nematodes, the body cavity is a pseudocoelom, which: a.) Is lined entirely by mesoderm b.) Is filled with blood c.) Acts as a hydrostatic skeleton d.) Is a true coelom

c.) Acts as a hydrostatic skeleton

In molluscs, the nervous system is generally described as: a.) Ladder-like with paired ventral nerve cords b.) Decentralized with a nerve net c.) Well-developed with a centralized brain in all species d.) Absent in bivalves

a.) Ladder-like with paired ventral nerve cords

The hemocoel is the primary body cavity in molluscs, in which blood circulates through an open circulatory system in most species. T/F

True. (Most molluscs, except cephalopods, have an open circulatory system.)

Nematodes undergo ecdysis, or molting, of their cuticle as they grow. T/F

True. (Nematodes are ecdysozoans, meaning they molt their cuticle.)

Earthworms (Oligochaeta) have trochophore larvae like polychaetes. T/F

False. (Earthworms develop directly without a trochophore larva.)

All molluscs use a radula for feeding. T/F

False. (Bivalves, for example, are filter feeders and lack a radula.)

Which structure in molluscs is homologous to the parapodia in polychaetes? a.) Foot b.) Mantle c.) Visceral mass d.) Radula

a. (The foot of molluscs serves a similar locomotory function as the parapodia of polychaetes.)

In terms of phylogeny, what is a major difference between annelids and nematodes? a.) Annelids have a true coelom, while nematodes are pseudocoelomates. b.) Nematodes undergo spiral cleavage, while annelids undergo radial cleavage. c.) Annelids are ecdysozoans, while nematodes are lophotrochozoans. d.) Nematodes have a closed circulatory system, while annelids do not.

a. (Annelids are coelomates, whereas nematodes are pseudocoelomates.)

Which of the following groups contains members that utilize a hydrostatic skeleton for movement? a.) Molluscs b.) Polychaetes c.) Nematodes d.) All of the above

What is a shared feature between tardigrades and nematodes in terms of their body structure? a.) Both are coelomates. b.) Both possess a cuticle that they molt. c.) Both have segmentation. d.) Both have parapodia for movement.

Polychaetes are primarily terrestrial annelids that rely on direct development. T/F

False. (Polychaetes are primarily marine and have trochophore larvae.)

The excretory system of earthworms (oligochaetes) involves specialized structures called: a.) Nephridia b.) Malpighian tubules c.) Flame cells d.) Antennal glands

a. nephridia

Which of the following is responsible for the buoyancy control in cephalopods? a.) Siphon b.) Radula c.) Mantle d.) Gas-filled chambers in the shell (e.g., in nautilus)

d.) Gas-filled chambers in the shell (e.g., in nautilus)

In nematodes, waste products are primarily excreted through: a.) Malpighian tubules b.) Protonephridia c.) Renette cells d.) Nephridia

c.) Renette cells

Which type of mollusc uses a crystalline style for digestion? a.) Cephalopods b.) Gastropods c.) Bivalves d.) Polyplacophora

c.) Bivalves

The body cavity of a mollusc is known as the: a.) Pseudocoelom b.) Hemocoel c.) Coelom d.) Gastrovascular cavity

c.) Coelom

Which of the following groups is most closely related to molluscs? a.) Annelids b.) Arthropods c.) Cnidarians d.) Echinoderms

a.) Annelids

Which of the following features is not unique to annelids? a.) Segmentation b.) Parapodia c.) Clitellum d.) Nephridia

d.) Nephridia

Polychaete worms primarily move through: a.) Undulating movements of the body wall b.) Contractions of the muscular foot c.) Siphon propulsion d.) Using their parapodia as paddles

d.) Using their parapodia as paddles

Which of the following groups of molluscs typically lacks a radula? a.) Gastropods b.) Cephalopods c.) Bivalves d.) Polyplacophorans

c.) Bivalves

The crystalline style in bivalves functions in: a.) Grinding food particles b.) Digestion and enzyme release c.) Waste excretion d.) Sensory perception

b.) Digestion and enzyme release

Gas exchange in polychaetes primarily occurs through: a.) Their parapodia b.) Gills located in the mantle cavity c.) Diffusion through the body surface d.) Tracheal systems

a.) Their parapodia

Which sensory structures are responsible for chemoreception in polychaetes? a.) Statocysts b.) Nuchal organs c.) Sensory tentacles d.) Compound eyes

b.) Nuchal organs

The excretory organs in earthworms are called: a.) Flame cells b.) Protonephridia c.) Nephridia d.) Renette cells

c.) Nephridia

Which class of annelids is characterized by the presence of a clitellum and direct development (no larval stage)? a.) Polychaeta b.) Hirudinea c.) Oligochaeta d.) Pogonophora

c.) Oligochaeta

Which clade within the Ecdysozoa is known for having a pseudocoelom and cuticle molting? a.) Arthropoda b.) Nematoda c.) Annelida d.) Mollusca

b.) Nematoda

Which of the following phyla is considered pseudocoelomate? a) Arthropoda b) Annelida c) Nematoda d) Mollusca

c) Nematoda

What function does the hydrostatic skeleton serve in nematodes? a) It helps in locomotion by providing buoyancy. b) It allows for muscle contractions to transmit force through fluid. c) It supports the digestive system. d) It protects against desiccation.

b) It allows for muscle contractions to transmit force through fluid.

Which of the following parasitic nematodes is known to block lymphatic vessels, causing elephantiasis? a) Ascaris lumbricoides b) Necator americanus c) Wuchereria spp. d) Trichinella spiralis

c) Wuchereria spp.

Which characteristic is unique to nematodes and contributes to their muscle coordination? a) Presence of a coelom b) Lack of motile cilia or flagella c) Lack of circular muscles d) Ability to regenerate

c) Lack of circular muscles

Panarthropoda is a monophyletic group that includes Onychophora, Tardigrada, and Arthropoda. T/F

True

In nematodes, amphids are a pair of sensory organs found near the posterior end of the body. T/F

False (Amphids are located near the anterior end of the body.)

Trichinella spiralis causes trichinosis, and infection occurs by consuming poorly cooked pork. T/F

true

The phylum Nematomorpha contains parasitic worms that infect arthropods. T/F

True (As juveniles, they are parasitic in arthropods but are free-living as adults.)

Which of the following is a characteristic of the Phylum Onychophora? a) They are primarily marine. b) They have a segmented body with paired appendages. c) They are commonly known as velvet worms. d) They lack a digestive system.

c) They are commonly known as velvet worms.

In Nematoda, which structures are involved in sensory perception? a) Ocelli b) Amphids and phasmids c) Statocysts d) Lateral line systems

b) Amphids and phasmids

Which of the following statements about nematode reproduction is true? a) They are hermaphroditic. b) Fertilization is usually external. c) They can produce between 100 and 100,000 eggs. d) They do not have distinct male and female forms.

c) They can produce between 100 and 100,000 eggs.

Nematodes have both circular and longitudinal muscles, allowing for complex movement. T/F

False (They only have longitudinal muscles.)

Kinorhynchs are characterized by a retractile proboscis and a spiny neck. T/F

True

Parasitic nematodes usually undergo a direct developmental cycle without any free-living juvenile stages. T/F

False (They may have free-living juvenile stages requiring intermediate hosts.)

The phylum Priapulida is characterized by having a distinct head and a pair of antennae. T/F

False (They lack a distinct head and have a eversible pharynx for feeding.)