Acoelomates: Phylum Platyhelminthes and Nemertea and
Pseudocoelomates: Phyla Nematoda and Rotifera & Parasitism
Lab #7 - Biological Sciences 102 – Animal Biology
7.1
This lab is designed to explore the basic life history, physiology and adaptations of the
acoelomate and pseudocoelomate animals with a focus on the Phyla Playthelminthes, Nemertea
(Rhynchocoela), Nematoda, Rotifera. We will review the lifecycles of many of these species
with an emphasis on their commonly parasitic nature. You must learn these lifecycles.
Refer to chapters in the Hickman text for illustrations,
diagrams, and additional information about acoelomates &
pseudocoelomates.
The Acoelomate Animals
The acoelomates are animals that have no coelom (body cavity). They include flatworms,
phylum Platyhelminthes (Gr. platys, flat, + helmins, worm); ribbon worms, phylum Nemertea
(Gr. Nemertes, one of the Nereids, mermaids of Greek mythology); and jaw worms, phylum
Gnathostomulida (Gr. gnathos, jaw, + stoma, mouth). In acoelomate animals, the space
between the body wall (ectoderm) and digestive tract (endoderm) is not a cavity, as in
coelomate animals, but is filled with muscle fibers and a loose tissue of mesenchymal
origin, called parenchyma, both derived from mesoderm. The presence of a well-developed
mesodermal layer makes the acoelomates triploblastic (having three germ layers: ectoderm,
endoderm, and mesoderm). Flatworms are a large and economically important group because
they include not only free-living planarians but also parasitic tapeworms and flukes.
Acoelomates are more complex in organization than the radiate animals in several ways:
¾ Acoelomates have bilateral symmetry
¾ They have defined tissues organized into functional organs
¾ They have a highly organized nervous system with concentration of nervous tissue and
sense organs in the anterior end (cephalization)
¾ They have an excretory system of specialized flame cells and tubules for elimination of
nitrogenous wastes (breakdown products of protein, nucleic acid and other metabolism)
¾ Platyhelminthes have a gastrovascular system, but ribbon worms have separated the
two functions and have a complete mouth-to-anus digestive tract and a circulatory system
¾ Flatworms have a tissue-organ level of organization
Body Plan Features Retained by Acoelomates (seen in previously studied phyla):
¾ true tissues present
Body Plan Features & Characteristics of Members of the Phylum Platyhelminthes
(not seen in the Phylum Cnidaria – some of these traits are seen in other animal phyla in
addition to the Phylum Platyhelminthes):
1. acoelomate
2. bilateral symmetry
3. triploblastic structure (endoderm, mesoderm and ectoderm)
4. some degree of cephalization = head with sensory organs
5. more organ systems (simple and formed of true tissues) are present
6. flame cells in flame bulbs for excretion
7. gastrovascular cavity for digestion and gas exchange (organs near body surface)
8. longitudinal, circular and ventro-dorsal muscles
9. hydrostatic skeleton (as muscles push against parenchyma and tissue fluids)
10. high surface-volume ratio as a result of flat shape (Important in locomotion and in
exchange of nutrients and wastes).
11. monoecious (hermaphroditic) = male and female organs in one individual
12. most are parasitic, but some are free-living
Acoelomates: Phylum Platyhelminthes and Nemertea and
Pseudocoelomates: Phyla Nematoda and Rotifera & Parasitism
Lab #7 - Biological Sciences 102 – Animal Biology
7.2
Classification & Adaptations of Acoelomate Animals
Phylum Platyhelminthes (flatworms)
Class Turbellaria (tur'bel-lar' e-a) (1. turbellae [pLJ, stir, bustle, + aria, like or connected with).
About 3000 species; Turbellarians. Mostly free-living, with a ciliated epidermis. A paraphyletic
grouping. Example: Dugesia tigrina.
Class Monogenea (mon'o-gen'e-a) (Gr. mono, single, + gene, origin, birth). About 1100 species;
Monogenetic flukes. Adult body covered with syncytial tegument without cilia; leaflike to
cylindrical in shape; posterior attachment organ with hooks, suckers, or clamps, usually in
combination; all parasitic, mostly on skin or gills of fishes; single host; monoecious; usually
free-swimming ciliated larva. Examples: Polystoma, Gyrodactylus.
Class Trematoda (trem'a-to'da) (Gr. trematodes, with holes, + eidos, form). About 10,000
species; Digenetic flukes. Adult body covered with nonciliated syncytial tegument; leaf-like or
cylindrical in shape; usually with oral and ventral suckers, no hooks; development indirect,
first host a mollusc, final host usually a vertebrate; parasitic in all classes of vertebrates.
Examples: Fasciola, Clonorchis, Schistosoma.
Class Cestoda (ses-to'da) (Gr. kestos, girdle, + eidos, form). About 3500 species; Tapeworms.
Adult body covered with non-ciliated, syncytial tegument; scolex with suckers or hooks,
sometimes both, for attachment; long, ribbonlike body, usually divided into series of
proglottids; no digestive organs; parasitic in digestive tract of all classes of vertebrates; first
host may be invertebrate or vertebrate. Examples: Taenia, Diphyllobothrium.
Phylum Nemertea or Rhynchocoela (ribbonworms)
About 600 species. Ribbon worms are often called nemertine or nemertean worms. Nearly all
are marine and are characterized by an eversible proboscis that can be thrown out with great
speed to capture food.
Ribbon worms have separated the two functions of the
gastrovascular cavity in flatworms and have a complete mouth-to-anus digestive tract and a
circulatory system. Nemerteans occur in the intertidal, under stones or sea weed, or in
burrows in muddy sand. Nemerteans can be very long at up to 50 meters (these species
are the worlds longest animals).
Body Plan Features & Characteristics of Members of the Phylum Nemertea
(some of these traits are seen in other animal phyla in addition to the Phylum Nemertea):
1.
2.
3.
4.
5.
6.
acoelomate, bilateral symmetry, triploblastic structure
some degree of cephalization = head with sensory organs
some organ systems (formed of true tissues) are present
eversible proboscis (only worm phylum with this characteristic)
complete digestive tract/system (from mouth-to-anus)
separate circulatory system with two lateral vessels on each side of the
gut and sinuses around head and tail; no definite closed circulation
7. flame cells for excretion
8. longitudinal and circular muscles contract against fibrous basement membrane;
multiple patterns of muscle fiber organization.
9. hydrostatic skeleton (as muscles push against parenchyma and tissue fluids)
10. dioecious with sexual reproduction or asexual fragmentation
11. not parasitic, free-living
Acoelomates: Phylum Platyhelminthes and Nemertea and
Pseudocoelomates: Phyla Nematoda and Rotifera & Parasitism
Lab #7 - Biological Sciences 102 – Animal Biology
7.3
The Pseudocoelomate Animals
A11 bilateral animal phyla except the acoelomates possess a body cavity belonging to one of
two types: (1) true coelom, in which a peritoneum (an epithelium of mesodermal origin)
covers both the inner surface of the body wall and the outer surface of the visceral
organs in the cavity, or (2) pseudocoel, a body cavity not entirely lined with peritoneum (one
layer of mesoderm attached to the ectoderm).
A body cavity of either type is an advantage because it provides room for organ development
and storage and allows some freedom of movement within the body. Because the cavity is
often fluid-filled, it also provides for a hydrostatic skeleton in those forms lacking a true
skeleton. There are nine pseudocoelomate phyla, of which phylum Nematoda is by far the
largest. All pseudocoelomate phyla are at the organ-system level of organization.
In general pseudocoelomates tend to be cylindrical in body form, to be unsegmented, and to
have a complete (mouth-to-anus) digestive tract (this is absent in acanthocephalans). The
epidermis is usually covered with a cuticle. There are both aquatic and terrestrial members,
and parasitism is fairly common.
Body Plan Features Retained by Pseudocoelomates (seen in previously studied phyla):
1. Presence of true tissues
2. bilateral symmetry
3. triploblastic structure (endoderm, mesoderm and ectoderm)
4. some degree of cephalization = head with sensory organs
5. some organ systems (formed of true tissues) are present
Body Plan Features & Characteristics of Pseudocoelomates:
1. possess a pseudocoelom (mesoderm lines ectoderm tissue side only)
2. they are unsegmented
3. complete digestive tract/system (from mouth-to-anus)
4. epidermis is covered with a cuticle
Acoelomates: Phylum Platyhelminthes and Nemertea and
Pseudocoelomates: Phyla Nematoda and Rotifera & Parasitism
Lab #7 - Biological Sciences 102 – Animal Biology
7.4
Classification & Adaptations of Pseudocoelomate Animals
Phylum Nematoda (roundworms)
More than 25,000 species. Roundworms. Nematodes are an extensive group with worldwide
distribution. They include terrestrial, freshwater, marine, and parasitic forms. They are
elongated roundworms covered with a flexible, nonliving cuticle. Circular muscles are lacking
in the body wall and, in Ascaris, longitudinal muscles are arranged in four groups separated by
epidermal cords (some nematodes have six or eight groups of longitudinal muscles). Cilia are
completely lacking. Nematodes are found free-living in almost every conceivable habitat from
arid deserts to lake bottoms, rivers, polar seas. Nematodes - both parasitic and freeliving - are
incredibly abundant. A handful of good garden soil contains thousands of nematodes. Some
50 different species of nematodes occur in humans, most of them nonpathogenic. Some
nematodes are plant parasites feeding on plant sap, especially roots.
Body Plan Features & Characteristics of Members of the Phylum Nematoda
(some of these traits are seen in other animal phyla):
1. pseudocoelomate
2. bilateral symmetry
3. triploblastic structure (endoderm, mesoderm and ectoderm)
4. psuedocoelomate = possess a pseudocoelom
5. some degree of cephalization = head with sensory organs
6. some organ systems (formed of true tissues) are present
7. vermiform (worm-like) body shape
8. complete digestive tract with three angled (longitudinal, circular and oblique)
muscular pharynx, intestine lacking muscular walls, short rectum and anus
9. excretion and osmoregulation through the cuticle and by excretory canals
10. lack both cilia and flame cells/bulbs
11. body wall lined with cuticle which retains body shape
12. longitudinal muscles only, no circular muscles in body wall; body length or
diameter does not change in movement
13. hydrostatic skeleton (as muscles push against parenchyma and tissue fluids)
14. dioecious; sexes separate with females larger than males; one or two tubular gonads;
copulatory spicules present in males
Phylum Rotifera (rotifers)
About 2000 species. The name "rotifer" is derived from the Latin word meaning "wheel-bearer";
this makes reference to the crown of cilia around the mouth of the rotifer. The rapid
movement of the cilia in some species makes them appear to whirl like a wheel. Rotifers can be
found in many freshwater environments and in moist soil. The habitat of rotifers may include
still water environments, such as lake bottoms, as well as flowing water environments, such as
rivers or streams. Rotifers are also commonly found on mosses and lichens growing on tree
trunks and rocks, in rain gutters and puddles, in soil or leaf litter, on mushrooms growing near
dead trees, in tanks of sewage treatment plants, and even on freshwater crustaceans and
aquatic insect larvae. Most species of rotifers are about 200 to 500 micrometers long. However
a few species, such as Rotaria neptunia may be longer than a millimeter. Rotifers are thus
multicellular creatures who make their living at the scale of unicellular protists. Characteristic
features of rotifers include the ciliated corona ("wheel organ") and the mastax. The corona is
located anteriorly and functions in locomotion and food gathering. The corona is modified
extensively in some species. The mastax is a muscular pharynx containing a complex set of
hard jaws or trophi and is found in all rotifers. These characteristics of these structures have
been used extensively in classifying rotifers.
Acoelomates: Phylum Platyhelminthes and Nemertea and
Pseudocoelomates: Phyla Nematoda and Rotifera & Parasitism
Lab #7 - Biological Sciences 102 – Animal Biology
7.5
Body Plan Features & Characteristics of Members of the Phylum Rotifera
(some of these traits are seen in other animal phyla):
1.
2.
3.
4.
5.
6.
bilateral symmetry and triploblastic structure (endoderm, mesoderm and ectoderm)
psuedocoelomate = possess a pseudocoelom
some degree of cephalization = head with sensory organs
some organ systems (formed of true tissues) are present
complete digestive system with mouth and anus
well muscularized pharynx = mastax that contains trophi (jaws) for sucking and
grinding food particles
7. ciliated corona helps sweep food particles to mouth
8. pair of protonephridial tubules for osmoregulation & excretion
9. syncitial (multinucleate) epidermis; some have a secreted cuticle
10. longitudinal muscles and circular muscles in body wall
11. pedal glands of foot secrete adhesive material in both sessile and creeping forms
12. hydrostatic skeleton (as muscles push against parenchyma and tissue fluids)
13. dioecious; sexes separate with females larger than males; one or two tubular gonads;
copulatory spicules present in males; can be parthenogenic
¾
Reproduction in Rotifers
¾
¾
¾
¾
¾
¾
single (male) or double set of gonads (female) and ducts in each sex
sexes separate (dioecious)
males unknown in class Bdelloidea and only occur a few weeks a years in the class
Monogononta
all females are parthenogenetic in the class Bdelloidea (diploid females produce
diploid females)
parthenogenesis = unisexual reproduction involving the production of young by
females that are not fertilized by males; common in rotifers, aphids, bees, ants and
wasps. Parthenogenetic eggs may be haploid or diploid.
In the class Monogononta, most of the year diploid females produce thin shelled
diploid amictic eggs. These amictic eggs develop parthenogenetically into diploid
(amictic) females. When the environment in the pond or stream changes due to
crowding, diet, change in photoperiod, etc. some amictic eggs develop into diploid
mictic females that produce thin shelled haploid eggs. If these eggs are not fertilized
then they will develop into haploid males. If the eggs are fertilized, they become
mictic eggs with a thick, resistant shell and become dormant. These “winter eggs”
can survive until the environment becomes more suitable at which time they hatch and
develop into amictic females (completing the cycle). Females grow and reach maturity
in a few days while males rarely grow and are mature at birth.
Acoelomates: Phylum Platyhelminthes and Nemertea and
Pseudocoelomates: Phyla Nematoda and Rotifera & Parasitism
Lab #7 - Biological Sciences 102 – Animal Biology
7.6
¾ Concepts Related to Parasitic Worms
Basic Requirements for a Parasitic Life
1. The parasite must have or obtain access to a host(s)
2. The parasite must establish itself and survive within the host(s)
3. The parasite must show successful reproduction and transmission to a new host
Special Parasitic Adaptations
1. Invasion of the host can occur through many mechanisms:
a. through the mouth with food and/or water
b. through the skin by penetration
c. through a vector such as a biting insect
2. Establishment and survival within a host requires:
a. transport of parasites/larvae/eggs in host through blood or lymph
b. resistance to host's defenses (such as resistance to immune cells, circulating
antibodies and acids and enzymes in the digestive tract for intestinal parasites)
3. Reproduction, by cross fertilization:
a. most trematodes and cestodes are monoecious (both sexes in one individual)
b. most nematodes are dioecious; generally, males are smaller than females.
4. Parasitic Worm Life Cycles
SEE THE DETAILED HANDOUT (ALSO AVAILABLE ON WEBSITE)
a. Fertilization occurs within a host and fertilization is internal as a result of
copulation. The parasite zygote develops into a shelled embryo which develops
into a larval stage(s).
b. SIMPLE PATTERN (monogenes, some tapeworms, nematodes)
ZYGOTE -----> LARVA -----> ADULT -----> MANY EGGS
c. COMPLEX PATTERN (digenes and some tapeworms)
ZYGOTE --> 1st LARVAL STAGE--> 2nd LARVAL STAGE-->
3rd LARVAL STAGE --> ADULT --> MANY EGGS
5. Digenetic trematodes and cestodes have specialized surfaces consisting of a
cellular syncytium with microvilli (microtrichs) which serve to increase the
absorptive surface up to 50 times. Membrane surface serves to protect against
host's digestive enzymes, serves in chemical modification of absorbed
solutes, and serves in membrane transport
Acoelomates: Phylum Platyhelminthes and Nemertea and
Pseudocoelomates: Phyla Nematoda and Rotifera & Parasitism
Lab #7 - Biological Sciences 102 – Animal Biology
7.7
LAB PROCEDURE
NAME:
LAB SCORE:
Refer to the textbook and the internet to help you answer the questions.
You must answer ALL questions in the lab procedure for full credit.
Finish them at home if you do not have time to complete them in lab.
Answer these questions:
List some advantages of bilateral symmetry over radial symmetry?
What advantages does cephalization offer for a bilateral animal?
Acoelomates and pseudocoelomates have excretory systems of specialized flame cells or
protonephridia for the elimination of nitrogenous wastes. How does a radiate animal, such as
a hydra or sea anemone, rid itself of waste molecules?
Cilia are completely lacking in nematodes. Are cilia present in any acoelomates?
Are cilia present in any cnidarians?
Acoelomates: Phylum Platyhelminthes and Nemertea and
Pseudocoelomates: Phyla Nematoda and Rotifera & Parasitism
Lab #7 - Biological Sciences 102 – Animal Biology
7.8
Phylum Platyhelminthes
Class Turbellaria = free-living flatworms
¾
¾
Observe the specimens and/or diagrams of the species listed below.
Record the descriptive information requested at the end of the lab for each species.
¾
¾
Dugesia sp., a triclad flatworm
an available polyclad flatworm
¾
What are the two major orders of flatworms in the Class Turbellaria?
¾ Observations of a Free-Living Planarian Flatworm
¾
Obtain a living specimen of Dugesia tigrina or Planaria sp. as available in a small
petri dish or watch glass and study it under the dissecting microscope.
Species name of your observed specimen:
¾
Note the gliding movement. What causes it?
¾
Using forceps, gently turn your flatworm over. Observe and describe the righting response.
¾
How long does the righting response take?
¾
Does the worm avoid obstacles such as a needle or probe without touching them?
¾
Locate the eyespots and the “ears” or auricular organs.
These organs contain
chemoreceptors. Place a small piece of liver in the dish and observe and record how the
worm responds.
Acoelomates: Phylum Platyhelminthes and Nemertea and
Pseudocoelomates: Phyla Nematoda and Rotifera & Parasitism
Lab #7 - Biological Sciences 102 – Animal Biology
7.9
¾
Do you think the response to the liver depends on the presence of the auricular organs?
¾
Briefly describe how you could test your hypothesis?
¾
Does the worm respond to differences in light intensity? Record your observations below.
¾
Record the reaction of the planarian to the addition of one drop of a 0.1% salt solution
placed in front of it.
¾
How do the two major types of turbellarian (Class Turbellaria) flatworms differ? (eg. How do
members of the Order Tricladida (triclad flatworms) differ from members of the Order
Polycladida (polyclad flatworms – how are their bodies different)?
Acoelomates: Phylum Platyhelminthes and Nemertea and
Pseudocoelomates: Phyla Nematoda and Rotifera & Parasitism
Lab #7 - Biological Sciences 102 – Animal Biology
7.10
¾ Observations of Planarian Flatworm Body Structures
¾
Using a microscope and the preserved, prepared slides identify the following structures of
Dugesia sp.or Planaria sp.
¾
Draw and CLEARLY label the Dugesia sp.or Planaria sp. whole mount.
¾
¾
eyespots
intestine
¾
Draw and CLEARLY label the Dugesia sp.or Planaria sp. cross section through the
pharynx.
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¾
¾
¾
intestine
diverticula
epidermis
pharynx
¾ Planaria Regeneration Experiments
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¾
¾
¾
¾
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auricular organs
pharynx
cilia
nerve cords
circular muscles
longitudinal muscles
Your instructor will perform incisions on some planarian flatworms to demonstrate
regeneration. We will culture and observe these specimens in lab over the next few weeks.
Acoelomates: Phylum Platyhelminthes and Nemertea and
Pseudocoelomates: Phyla Nematoda and Rotifera & Parasitism
Lab #7 - Biological Sciences 102 – Animal Biology
7.11
Phylum Platyhelminthes
Class Trematoda = flukes
¾
¾
Observe the specimens and/or diagrams of the species listed below.
Record the descriptive information requested at the end of the lab for this species.
¾ Opisthorchis (Clinorchis ) sinensis = human liver fluke
¾ Observations of Trematode Body Structures
¾
Using a microscope and the preserved, prepared slides identify the following structures of
trematodes.
¾
Draw and CLEARLY label the Opisthorchis (Clonorchis) sinensis. whole mount.
¾
¾
¾
¾
¾
¾
oral sucker
ventral sucker
pharynx & intestines
excretory canals/ducts
uterus
ovary (as visible)
¾
Why do you think this species lacks a complete gut (it has only one opening, not really
an anus)?
¾
Then why is a gut/intestine present at all?
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¾
¾
¾
¾
yolk gland (as visible)
anterior & posterior testes
vas deferens (as visible)
seminal receptacle (as visible)
bladder
Acoelomates: Phylum Platyhelminthes and Nemertea and
Pseudocoelomates: Phyla Nematoda and Rotifera & Parasitism
Lab #7 - Biological Sciences 102 – Animal Biology
7.12
¾ Observation of an Example of Trematode Copulation
¾
¾
Draw the male and female Schistosoma mansoni in copulation from a prepared slide
indicating which sex is which.
What aspect of their reproduction is unusual with respect to other trematode species?
Phylum Platyhelminthes
Class Cestoda = tapeworms
¾
¾
Observe the specimens and/or diagrams of the
species listed below.
Record the descriptive information requested at the
end of the lab for this species.
¾ one adult cestode tapeworm on display
¾ Observation of Cestode Body Structures
¾
Using a microscope and the preserved, prepared slides identify the following structures of
cestodes.
¾
Examine a prepared slide of a scolex (head) from a tapeworm such as Taenia sp. or
Diplidium sp. .
¾
Sketch and label the scolex. Label the four suckers, and the hooks.
¾ Examine a slide of a gravid proglottid of a cestode. Note the following structures:
(you do not need to draw this, but you should be able to identify these in a diagram)
¾
¾
¾
¾
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nerve cords (as visible)
male reproductive structures are not easily
excretory canals
visible in a gravid proglottid
vagina/genital pore
Note how the ova are packed into the branched uterus
Roughly, how many eggs are their per gravid proglottid?
(are there 10s, 100s, 1000s, millions of eggs per gravid proglottid?)
Acoelomates: Phylum Platyhelminthes and Nemertea and
Pseudocoelomates: Phyla Nematoda and Rotifera & Parasitism
Lab #7 - Biological Sciences 102 – Animal Biology
7.13
Phylum Nemertea (Rhynchocoela = ribbonworms)
¾
¾
Observe the specimens and/or diagrams of the species listed below.
Record the descriptive information requested at the end of the lab for this species.
¾ Baseodiscus punneti or other
Phylum Nematoda (roundworms)
¾
¾
Observe the specimens and/or diagrams of the species listed below.
Record the descriptive information requested at the end of the lab for this species.
¾ Ascaris lumbricoides = human intestinal parasite
¾ Observation of Nematode Body Structures
¾
Using a microscope and the preserved, prepared slides identify the following structures of
cestodes.
¾
Examine a prepared slide of Ascaris lumbricoides male and female. Note the
following structures: (you do not need to draw this, but you should be able to
identify these in a diagram)
¾
¾
¾
¾
epidermis
cuticle
muscle cells & processes
intestine
¾
In the female Ascaris cross section locate the following:
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¾
¾
ovary
oviduct
uterus Can you recognize the ova?
¾
In the male Ascaris cross-section (on the same slide) locate the :
¾
¾
testes
vas deferens (as visible)
¾
¾
¾
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pseudocoel
longitudinal muscles
lateral lines/cords
excretory canals (as visible)
¾ Observation of a Free-Living Nematode Roundworm
Obtain a sample of living “vinegar eels”, Turbatrix aceti, and examine under the 10X
objective of the compound microscope. You may want to add Proto-Slo to the
preparation before adding the cover slip.
¾ Note the direction of movement, which is actually dorso-ventral (rather than
lateral) bending.
¾ What is about the muscular structural arrangement in nematodes that permits
only this characteristic “whip-like” motion?
Acoelomates: Phylum Platyhelminthes and Nemertea and
Pseudocoelomates: Phyla Nematoda and Rotifera & Parasitism
Lab #7 - Biological Sciences 102 – Animal Biology
¾
7.14
Is the reproductive cycle of Turbatrix aceti as complex as that of Ascaris
lumbricoides? Why, or why not do you think this is the case?
Phylum Rotifera (rotifers)
¾
¾
Observe the specimens and/or diagrams of the species listed below.
Record the descriptive information requested at the end of the lab for this species.
¾ a rotifer (you will probably be unable to identify it to species, so just provide a
common name)
¾
Examine the culture of rotifers. Examine a sample on a slide with Proto-Slo under
the compound microscope.
¾
Draw and CLEARLY label the following rotifer structures, otherwise be able to
identify the following structures:
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¾
¾
¾
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corona
mastax (jaw apparatus)
trochus (ciliated whorls)
stomach
intestine
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¾
¾
¾
mouth
foot and toes (for anchoring)
cloacal bladder (as visible)
pedal glands (as visible)
eyespots near brain (as visible)
Acoelomates: Phylum Platyhelminthes and Nemertea and
Pseudocoelomates: Phyla Nematoda and Rotifera & Parasitism
Lab #7 - Biological Sciences 102 – Animal Biology
7.15
For the live specimens available for observation in the lab, record the requested
information.
Phylum Platyhelminthes
Class Turbellaria
Order Tricladida
Scientific name: Dugesia sp. or other
Common name:
General dimensions of specimen:
Unique structures or features:
Draw a simple sketch to remind you of the basic structure of this species and any unique
characteristics observed.
Notes & observations to help you remember and distinguish this group/species:
Acoelomates: Phylum Platyhelminthes and Nemertea and
Pseudocoelomates: Phyla Nematoda and Rotifera & Parasitism
Lab #7 - Biological Sciences 102 – Animal Biology
7.16
Phylum Platyhelminthes
Class Turbellaria
Order Polycladida
Scientific name of a polyclad turbellarian:
Common name:
General dimensions of specimen:
Unique structures or features:
Draw a simple sketch to remind you of the basic structure of this species and any unique
characteristics observed.
Notes & observations to help you remember and distinguish this group/species:
Acoelomates: Phylum Platyhelminthes and Nemertea and
Pseudocoelomates: Phyla Nematoda and Rotifera & Parasitism
Lab #7 - Biological Sciences 102 – Animal Biology
7.17
Phylum Platyhelminthes
Class Trematoda
Scientific name: Opisthorchis (Clinorchis) sinensis or other
Common name:
General dimensions of specimen:
Unique structures or features:
Draw a simple sketch to remind you of the basic structure of this species and any unique
characteristics observed.
Notes & observations to help you remember and distinguish this group/species:
Fluke lifecycle
Acoelomates: Phylum Platyhelminthes and Nemertea and
Pseudocoelomates: Phyla Nematoda and Rotifera & Parasitism
Lab #7 - Biological Sciences 102 – Animal Biology
7.18
Phylum Platyhelminthes
Class Cestoda
Scientific name:
Common name:
General dimensions of specimen:
Unique structures or features:
Draw a simple sketch to remind you of the basic structure of this species and any unique
characteristics observed.
Notes & observations to help you remember and distinguish this group/species:
Pig Tapeworm Lifecycle
Acoelomates: Phylum Platyhelminthes and Nemertea and
Pseudocoelomates: Phyla Nematoda and Rotifera & Parasitism
Lab #7 - Biological Sciences 102 – Animal Biology
7.19
Phylum Nemertea (Rhynchocoela)
Class (check ITIS):
Scientific name: Baseodiscus punneti or other
Common name:
General dimensions of specimen:
Unique structures or features:
Draw a simple sketch to remind you of the basic structure of this species and any unique
characteristics observed.
Notes & observations to help you remember and distinguish this group/species:
Acoelomates: Phylum Platyhelminthes and Nemertea and
Pseudocoelomates: Phyla Nematoda and Rotifera & Parasitism
Lab #7 - Biological Sciences 102 – Animal Biology
7.20
Phylum Nematoda
Class (check ITIS):
Scientific name: Ascaris lumbricoides
Common name:
General dimensions of specimen:
Unique structures or features:
Draw a simple sketch to remind you of the basic structure of this species and any unique
characteristics observed.
Notes & observations to help you remember and distinguish this group/species:
Acoelomates: Phylum Platyhelminthes and Nemertea and
Pseudocoelomates: Phyla Nematoda and Rotifera & Parasitism
Lab #7 - Biological Sciences 102 – Animal Biology
7.21
Phylum Nematoda
Class (check ITIS):
Scientific name:
Common name:
General dimensions of specimen:
Unique structures or features:
Draw a simple sketch to remind you of the basic structure of this species and any unique
characteristics observed.
Notes & observations to help you remember and distinguish this group/species:
Acoelomates: Phylum Platyhelminthes and Nemertea and
Pseudocoelomates: Phyla Nematoda and Rotifera & Parasitism
Lab #7 - Biological Sciences 102 – Animal Biology
7.22
Phylum Rotifera
Class (check ITIS):
Scientific name:
Common name:
General dimensions of specimen:
Unique structures or features:
Draw a simple sketch to remind you of the basic structure of this species and any unique
characteristics observed.
Notes & observations to help you remember and distinguish this group/species:
Acoelomates: Phylum Platyhelminthes and Nemertea and
Pseudocoelomates: Phyla Nematoda and Rotifera & Parasitism
Lab #7 - Biological Sciences 102 – Animal Biology
LABORATORY NOTES:
Platodes by Haeckel
7.23
Acoelomates: Phylum Platyhelminthes and Nemertea and
Pseudocoelomates: Phyla Nematoda and Rotifera & Parasitism
Lab #7 - Biological Sciences 102 – Animal Biology
LABORATORY NOTES:
7.24