Exam 2 Study Guide (Revised) Flashcards
what is the cell type that secretes skeletal elements of the sponge?
amoeboid; called sclerocyte
which class of platyhelminthes is not parasitic?
turbellaria
parthenogenesis is the laying of ____ eggs
unfertilized
what kind of cells are located between the outer epidermis and digestive tract?
parenchymal cells
sponges from the class Homoscleromorpha have:
a true basement membrane
adherens cell junctions
a pinacoderm which is true tissue layer
all of the above
all of the above
all of the following are characteristic members of the phylum Porifera except which?
asymmetrical
three main cell types
central cavity, or a series of branching chambers, through which water circulates during filter feeding
diploblastic tissue organization
diploblastic tissue organization
all of the following are characteristic of members of the phylum Cnidaria except which?
radial or modified biradial symmetry
gelatinous mesoglea located between epidermal and gastrodermal tissue layers
triploblastic tissue
cnidocytes used in defense, feeding, and attachment
triploblastic tissue
the largest and most prominent stage in the life cycle of most members of the class Scyphozoa is the
medusa
planula
polyp
ephyra
medusa
the hydranth (gastrozoid) is the reproductive polyp in the Obelia life cycle
True or False
false
some anthozoans live in a mutualistic relationship with protists called zooxanthellae and are largely responsible for the formation of coral reefs
true or false
true
cnidocytes produce nematocysts that are discharged on stimulation of a cnidocil. cnidocytes are produced only in members of the phylum Cnidaria.
true or false
true
in most Porifera, the zygote develops into planktonic larva
true or false
false
Cells are never present in the mesoglea of cnidarians.
a.) True
b.) False
b.) False
In an ascon sponge, choanocytes _________________________.
a.) line radial canals that branch off the spongocoel
b.) line the spongocoel directly
c.) are found in flagellated chambers
d.) line incurrent canals
b.) line the spongocoel directly
Which of the following cell types is involved with creating water currents during filter feeding of a sponge?
a.) pinacocytes
b.) choanocytes
c.) porocytes
d.) archaeocytes
b.) choanocytes
The leucon body form is seen in the Class ____________________.
a.) Demospongiae
b.) Calcarea
c.) Hexactinellida
d.) all of the above
e.) none of the above
d.) all of the above
Gemmules are resistant capsules filled with pinacocyte cells.
a.) True
b.) False
b.) False
The soft corals have ____________ pinnate tentacles.
a.) 6
b.) 2
c.) 8
d.) 4
c.) 8
Acoelomates lack a body cavity because the
__________ cells completely fill the area
between the outer epidermis and digestive
tract
parenchymal
Cell types of Phylum Porifera
- Choanocytes
- Archaeocytes
- Pinacocytes
The sessile, tubular form of a cnidarian with a mouth and tentacles at one end and a basal disk at the other
Polyp
Cnidarian; colonial animal composed of different polyps that function together as a single organism; e.g. Obelia and Physalia
hydroid
A cnidarian body plan characterized by a bowl shape and adapted for a free-swimming life.
Medusa
Digestive chamber with a single opening, in which cnidarians, flatworms, and echinoderms digest food
gastrovascular cavity
a structure at the aboral end of a polyp used for attachment
pedal disc
-Type of cells are responsible for movement in Hydra
-form most of epidermis that cover organism and function in muscle contraction
epitheliomuscular
in cnidarians, the layer of cells surrounding the digestive tract
Gastrodermis
-in cnidarians, the jellylike material located between the ectoderm and the endoderm
-are gelatinous (at least 95% water) with epidermal and gastrodermal cells sending processes into it
Mesoglea
Special stinging structures on cnidarians that look like small harpoons.
Cnidocytes
In cnidarians, a stinging cell that is used to inject a toxin into prey
nematocyst
In aquatic osteichthyans, a protective bony flap that covers and protects the gills.
operculum
An organelle characteristic of the cnidaria that is used in defense, food gathering, and attachment.
cnida
Free-living forms
Parasitic forms
Leaf-like body
Length varies
Ribbon-like body
which phylum?
Phylum Platyhelminthes.
which class?
Most are free-living.
Their gut can be simple, branched, or absent.
They can be up to 50 cm long
turbellarians
monoecious means
both male and female sex cells in one body
zygote is retained within parent and provided with nourishment until it is released as ciliated larva; most sponges are this
viviparous
sponges release both sperm and oocytes into water for external fertilization
oviparous
The free-swimming larva of most sponges is a solid-bodied ____
parenchymula
which class of porifera is defined by:
Calcareous sponges with spicules
of calcium carbonate
– Spicules are straight (monaxons)
or have three or four rays
– Most are small with tubular or
vase shapes
– Many are drab in color, but some
are bright yellow, green, red, or
lavender
– Leucosolenia (Scypha) and Sycon
(Grantia) are marine shallow-
water
– Asconoid, syconoid and leuconoid body forms
class calcarea
which class of porifera is defined by:
Glass sponges with six-rayed spicules of
silica bound together to form network
– Deep-sea; vase or funnel shaped bodies
attached by stalks of root spicules onto the
substrate (radial symmetry in some)
– Have syncytial cell structure
class hexactinellida
which class of porifera is defined by:
Contains 95% of living sponge species include most large sponges
– Spicules are siliceous but not six rayed and may be absent or bound together by spongin
– Leuconoid body form for all species
– All marine except for Spongillidae, the freshwater sponges
– Marine demosponges are highly varied in color and shape, with some growing to several meters in diameter.
class demospongiae
which class of porifera is defined by:
-Mostly marine with a variety of colors but live in cryptic habitats
– Generally found near shore but
have deep water forms
– true
basement membrane
(extracellular matrix; ECM) under pinacoderm
– Also have adherens cell
junctions that form true tissues unlike other sponges
– Divided into two clades based
on absence or presence of
spicules
class homoschleromorpha
what trait of sponges is homologous to other animals?
proteins for cell adhesion and cell-signaling
are cnidarians typically sessile (free-floating)
yes
cnidarians start with zygotes developing into _____, which settles on hard substrate and metamorphoses into a polyp
planula
what is an operculum in phylum Cnidaria?
covers the end of a nematocyst (cnidae)
how do polyps tend to feed and digest?
since they are carnivorous, they catch prey with tentacles and pass them to the gastrovascular cavity
these are the derived traits of what class?
-velum in medusae
-medusae produced by lateral budding and endocodon
hydrozoa
these are the derived traits of what class?
-complex eyes
-velarium
-boxlike medusa body
cubozoa
these are the derived traits of what class?
-strobilation
staurozoa
these are the derived traits of what class?
-gut with septal filaments
-siphonoglyph
-anthozoan pharynx
-hexaradial and octaradial symmetry
anthozoa
difference between thecate and athecate hydranth?
protective cup, naked polyp
what is the difference between monoecious and dioecious species?
monoecious means asexual production (produces both female and male)
dioecious means that two organisms create both
what does protandrous mean?
producing sperm first and eggs later
A grouping used by scientists to refer to all multicellular animals is
porifera.
opisthokont.
protozoan.
metazoan
metazoan
Select all of the following that describe choanocytes.
They are flagellated collar cells
They maintain a current of water through the canals of the sponge
They can trap and phagocytize food particles
They form the pinacoderm
They secrete spicules and the collagen that forms spongi
They are flagellated collar cells
They maintain a current of water through the canals of the sponge
They can trap and phagocytize food particles
Incoming water enters a sponge through
oscula.
ascon.
spongocytes.
dermal pores.
dermal pores.
In a syconoid sponge, small lateral openings called ______ let water into the radial canals from the incurrent canals.
ostia
oscula
prosopyles
stolons
prosopyles
Sponge cells that can phagocytize food particles and differentiate into other cell types like spongocytes are called ____
archaeocytes
Select all of the following that describe archaeocytes.
They differentiate into more specialized cells.
They are phagocytes.
They form the external covering.
They are ameboid cells.
They differentiate into more specialized cells.
They are phagocytes.
They are ameboid cells.
Rotifers and acanthocephalans are lophotrochozoans but are
______
pseudocoelomate
acoelomorphs (phylum) have (in terms of digestion and nervous systems)
no gut and a radial arrangement of nerves
which phylum has an external body covering called a neodermis with cellular ciliated epidermis?
platyhelminthes
– Have flame cells which are cupshaped structures that have flagella
extending from the surface
– Beating flagella drive fluids down
collecting ducts and through
delicate interlaced projections
– Wall of the duct bears folds or
microvilli to resorb ions and
molecules
– Majority of metabolic wastes
removed by diffusion across the
wall
– The collecting ducts join and
empty at nephridiopores to regulate water
flatworms
which class?
Mostly free-living and range
from 5 mm to 50 cm long
* Lives under objects in marine,
freshwater and terrestrial habitats
* combine creeping
with ciliary movements while
very small planaria swim by cilia
* Others move by gliding over a
slime track secreted by marginal
adhesive glands and using
rhythmical muscular waves that
pass backwards from the head
turbellaria
explain the life cycle of the common liver fluke
When the eggs meet the water, they hatch into hairy larvae (miracidium), which takes 9 to 21 days to complete this process into the liver fluke larvae. Liver fluke larvae will choose snails of the genus Limnea as an intermediate host and develop into tail larvae (cercaria) over a period of 6 to 7 weeks.
Miracidium - Free living
* Sporocyst - Snail
* Redia - Snail
* Cercaria - Free living
* Metacercaria - Plant / Animal
which phylum?
Microscopic, aquatic animals
(inhabiting sediments of marine and
freshwater environments) with a
head, neck, and trunk
* Numerous adhesive glands are
present
* Marine species are generally
hermaphroditic
* Parthenogenesis (laying unfertilized
eggs) is common in freshwater
species
* Protonephridia possess a single
flagellum instead of cilia found in
flame cells
gastrotricha
(laying unfertilized
eggs
Parthenogenesis
have ducts that empty into excretory bladder that leads to the outside
via a terminal pore. which class?
trematodes
have two main excretory canals on each side that are continuous along
the length of the worm and join on the last segment and opens to the terminal pore. which class?
Cestodes
beef tapeworm life cycle
Once ingested, they release the scolex, then the tapeworm develops in the human small intestine and in 3 months, mature rings actively migrate through the anal sphincter. The lifespan of cysticerci is variable, some degenerate in 9 months, but others may remain viable for several years.
Onchosphere
* Found in egg
* Digestive enzymes release it
*Cysticerus
* Bladder worm
* Form fluid filled bladder
* Encyst in muscle
Taenia solium
* Pork Tapeworm
* Cysticercosis
Microscopic, aquatic animals
(inhabiting sediments of marine and
freshwater environments) with a
head, neck, and trunk
* Numerous adhesive glands are
present
* Marine species are generally
hermaphroditic
* Parthenogenesis (laying unfertilized
eggs) is common in freshwater
species
* Protonephridia possess a single
flagellum instead of cilia found in
flame cells
which phylum?
Phylum Gastrotricha
which phylum is not lophotrochozoan?
mesozoa
which 6 phylum are lophotrochozoan?
platyhelminthes, gastrotricha, gnathifera, micrognathozoa, rotifera, acanthocephala
(jawed worms)
– Found mostly in interstitial
spaces of very fine sand,
sediment and silt from the coasts
to the deep sea.
– Can endure very low oxygen and
live in association ciliates,
tardigrades and worms
– Feed by scraping bacteria and
fungi from the substrate with
paired jaws on the pharynx
– Acoelomate with no circulatory
system but use diffusion for
excretion and gas exchange
– Protandric or simultaneous
hermaphrodite that can cross fertilize internally forming single
zygote
Phylum Gnathostomulida
Mostly small animals living
interstitially with a two-part head,
thorax and abdomen leading to short
tail
– Has dorsal plates but no ventral ones
and use cilia to move with a ventral
adhesive pad that produce glue
– Have three pairs of complex jaws with
mouth leading to simple gut and anus
– Has protonephridia but reproductive
system is not well understood
Phylum Micrognathozoa
Tripoblastic, bilateral, unsegmented,
pseudocoelomates
– Complete digestive system, regionally
specialized
– Anterior end often has a ciliated organ
called a corona
– Posterior end with toes and adhesive
glands
– Well-developed cuticle
– Protonephridia with flame cells
– Males generally reduced in numbers or
absent; parthenogenesis common
Phylum Rotifera
explain the Rotifera Life Cycle
The life cycle of a rotifer is characterized by alternating between asexual reproduction through parthenogenesis (producing only females) and sexual reproduction, where environmental cues trigger the production of males, leading to the creation of resting eggs that can survive harsh conditions; most rotifers primarily reproduce asexually until unfavorable conditions prompt the switch to sexual reproduction to produce resistant eggs.
Amitic eggs
diploid; mitosis
* Mitic eggs
haploid; meiosis
changes depending on environmental stimuli (fall rain, winter)
are endoparasites in the
intestinal tract of vertebrates
* The body of an adult is elongate and
composed of a short anterior proboscis, a neck
region, and a trunk
* The retractable proboscis provides the means
of attachment in the host’s intestine
* Tegument – absorb food
* Dioecious
* have unique embryo
selective apparatus system
Phylum Acanthocephala
a (middle animals)
– Considered a “missing link”
between protozoa and metazoa
– Usually minute, ciliated, and
wormlike animals that live as
parasites or symbionts in
marine invertebrates
– Arranged in two layers of 20-30
cells not related to animal germ
layers of metazoans
* Live in kidneys of benthic
cephalopods
* Adults called vermiforms and are
long and slender
* Asexual reproduction consists of a
multinucleated mass called a
plasmodium that give rise to males
and females
Phylum Mesozoa
what are lophophores? (function)
have a crown of ciliated tentacles that are used in food capture
and respiration
– Cavity inside the lophophore is part of the coelom and filled with coelomic
fluid
– Thin ciliated walls act as respiratory surface for gas exchange
– Lophophores normally extended but can be withdrawn for protection
which phylum use lophophores?
ectoprocta, brachiozoa, phoronida
Members of this phylum live on
the mouthparts of the claw
lobster
– 0.35 mm long (0.10 mm wide)
* Dwarf males emerge and seek
out another female symbiont
– During lobster molt
* Free swimming individuals seek
another host
Phylum Cycliophora
Similar to Platyhelminthes, but can be
much larger
– Have fluid filled sac, primitive coelom
* Prey on invertebrates, which they capture
with a unique probosis held in a sheath
called a rhynchocoel
* They have a complete digestive tract
(mouth and anus)
* Blood-vascular system
– Primitive circulatory system
– Two lateral blood vessels
* Dioecious
* Fertilization results in a helmet shaped,
ciliated pilidium larva
Phylum Nemertea
which class?
The polyp stage is usually asexual.
Most are colonial in form.
Some lack a medusa stage in the life cycle.
hydrozoa
Members of what cnidarian class have the following characteristics:
a medusa stage ranging from 2 cm to 2 m in diameter, a bell that lacks a velum and can vary from a shallow saucer shape to a deep helmet or goblet shape, and sense organs called rhopalia?
Scyphozoa
which class?
An adhesive disc that attaches to objects on the ocean floor
A polyp that resembles a medusa, with eight arms surrounding the mouth
A solitary stalked polyp body form
staurozoa
which class?
Each rhopalium contains six eyes.
The base of a tentacle is differentiated into a flattened, tough blade called a pedalium.
The edge of the subumbrella turns inward to form a velarium.
cubozoa
which class?
The gastrovascular cavity is partitioned by septa.
They can be solitary or colonial.
Many forms produce a skeleton for support.
anthozoa
Biradial marine animals that typically use eight rows of cilia for locomotion are members of what taxonomic group?
(phylum)
Ctenophora
What phylum is distinguished by a cylindrical, invaginable proboscis?
Acanthocephala
Relatively small planktonic marine predators that have torpedo-shaped bodies and mouths bearing sickle-shaped bristles on each side make up what phylum?
Chaetognatha
Acanthocephalans are dioecious.
T/F
True
which phylum?
Parasites
Symbionts
Two-layered body
Ciliated worm-like exterior
mesozoans
which phylum?
Cilia around mouth
U-shaped gut with anus
cycliophora
which phylum?
Ciliary feeders
Solitary or colonial sessile organisms
most less than 0.5mm in size
encrust firm surfaces
colony builders (zooid)
entoprocta
Small, worm-like marine organisms that secrete a leathery or chitinous tube in which they live
They live in a leathery or chitinous tube.
They are marine organisms.
Their lophophore creates water current.
They are worm-like animals.
Phylum?
phoronida
which phylum?
They are bottom dwelling species.
They prefer shallow water marine habitats.
They have a fleshy stalk called a pedicel.
It contains the living form called Lingula.
It was most prominent and diverse in the Paleozoic and Mesozoic.
brachiopods
It contains the living form called Lingula.
It was most prominent and diverse in the Paleozoic and Mesozoic.
It contains the ribbon worms.
Nearly all are marine.
Extracellular in a complete digestive tract.
which phylum?
nemertea
The ciliated epidermis and flame cells in nemerteans show that they were once taxonomically aligned with the Phylum
Platyhelminthes
Sponges have all of the following characteristics except:
A highly specialized cells
B simple tissues
C a gel-like matrix
D cell recognition
E complex multicellularity
B Simple tissues
Water taken in through the pores in sponges exits through the:
A gastrovascular cavity
B spicules
C mesoglea
D osculum
E coelenteron
D osculum
Digestion in Leucosolenia and other sponges is
A only extracellular
B first extracellular, then intracellular
C only intracellular
D first intracellular, then extracellular
E sponges do not digest
C only intracellular
Which of the following is not a characteristic of a sponge?
A filters water
B has collar cells
C has stinging cells
D has mesohyl
E reproduces asexually and sexually
C has stinging cells
Which of the following describes the feeding behavior of cnidarians?
A They are carnivores
B They are herbivores
C They are autotrophs
D They are decomposers
E They are omnivores
A they are carnivores
Which of the following is not a characteristic found in cnidarians?
A tissues
B asexual reproduction
C sexual reproduction
D organs
E symmetry
D organs
A cnidocyte is a specialized cell used for:
A sensing light
B digesting food
C capturing food
D sensing movement
E circulating water
C capturing food
All statements about nematocysts below are correct except:
A the osmotic pressure of a nematocyst may exceed 100 atmospheres
B nematocysts are only used by cnidarians
C stings from nematocysts may be fatal
D nematocysts turn inside out when fired
E nematocysts are a cnidarian synapomorphy
B nematocysts are only used by cnidarians
The scyphozoa are called jellyfish because of their
A mesoderm
B mesenchyme
C mesoglea
D mesentery
E pectin
C mesoglea
How do ctenophores capture their food?
A Filter feeding
B Cnidocytes
C Radula
D Colloblasts
E Nematocysts
D colloblasts
A term that refers to non-hermaphroditic helminths is _.
A Monoecious
B Digenetic
C Monogenetic
D Heterooxenous
E Dioecious
E Dioecious
The first larval stage that is typical of mollusks is the:
A veliger
B ephyra
C planula
D cydippid
E trocophore
E trocophore
Cartilagenous structure that supports the radula
A Spicules
B Visceral mass
C Teeth
D Odontophore
E Buccal mass
D Odontophore
