Lab 3 Cnidaria and Ctenophora - EVERYTHING
- Obelia occurs as a _____ polyp where Hydra occurs as a _____ polyp. - Obelia has _____ polyps (gonangia), Hydra does not. - _____ is more sessile (Hint: Obelia or Hydra?)
- Obelia occurs as a colonial polyp where Hydra occurs as a solitary polyp. - Obelia has reproductive polyps (gonangia), Hydra does not. - Obelia is more sessile
What is the function of the combs of ctenophores?
- Used for locomotion - Produce colors via diffraction of light (not typically bioluminescent)
Match the structures below with the corresponding letter pointing at them in the image 1. _____ and _____ septa 2. _____ tentacles 3. _____ pedal disc 4. Identify the space indicated by line D _____ 5. What modification do sea anemones possess to increase their digestive surface area?
1. A, E 2. F 3. B 4. Pharynx 5. Septa
What is the order of the reproductive cycle of Phylum Cnidaria Class Scyphozoa?
1. Ciliated Planula Larva 2. Scyphistoma 3. Strobila 4. Ephyra
1. What is the specific name of the structure indicate by line A? 2. What is the function of the structure indicated by line A? 3. What is the specific name of the structure indicated by line B? 4. What is the function of the structure indicated by line B?
1. Hydranth (gastrozooid) 2. Feeding 3. Gonangium (gonozooid) 4. Reproduction
1. How many embryonic layers does the organism shown have? 2. What are the layers called? 3. What is the name having a body derived from only two embryonic cell layers called?
1. Two embryonic layers 2. Endoderm and ectoderm 3. Diploblastic
Which of the following is a similarity between the scyphozoan medusa and the hydrozoans medusa bud of Obelia? A) Both are radially symmetrical with tentacles surrounding the mouth B) Scyphozoan medusa are generally the same size as hydrozoan medusa with similar number of tentacles. C) Hydrozoan medusae possess a velum, but lack the oral arms that scyphozoan jellyfish possess.
A) Both are radially symmetrical with tentacles surrounding the mouth
CNIDARIA EXCRETORY/OSMOREGULATION:List how the group eliminates waste from their systems (e.g. diffusion, nephridia, Renette cells, Malpighian tubules etc.). A)Diffusion B)Protonephridia = Flame cell C)Metanephridia D)Nephridia E)Malpighian tubules
A) Diffusion
CNIDARIA RESPIRATION:Describe how the group respires (e.g. diffusion, book lungs, gills, etc.). Via: A)Diffusion B)Book lungs C)Lungs D) Book gills E) Tube feet that take up oxygen from water
A) Diffusion
CNIDARIA EMBRYONIC DEVELOPMENT:List the characteristics found during the formation of the blastula (e.g. triploblastic, deuterostome, etc.). A) Diploblast B)Triploblast C)Protostome D)Deuterostome E)Acoelomate (Triploblastic) F)Pseudocoelomate G)Eucoelomate (o coelomate) H)No embryonic development
A) Diploblast
CTENOPHORA EMBRYONIC DEVELOPMENT:List the characteristics found during the formation of the blastula (e.g. triploblastic, deuterostome, etc.). A) Diploblast B)Triploblast C)Protostome D)Deuterostome E)Acoelomate (triploblastic) F)Pseudocoelomate G)Eucoelomate (o coelomate) H)No embryonic development
A) Diploblast
CNIDARIA SKELETON/SUPPORT:List the structures or ways this group of animals support themselves (e.g. hydrostatic skeleton, exoskeleton, etc.). A)Hydrostatic skeleton B)Endoskeleton C)Spicules and spongin D)Exoskeleton
A) Hydrostatic skeleton
What is the structural equivalent of the chambers of leuconoid sponges in the Scyphozoa? A) thick layer of mesoglea B ) a branched gastrovascular cavity C) a very large number of tentacles D) asexual reproduction in the polyp stage
B ) a branched gastrovascular cavity
What is this a picture of?
Discharged nematocyst
What are the representative animals of the Phylum Cnidaria Class Scyphozoa?
Jellyfish (Aurelia)
What is the phylum, class, genus, and body form of this organism? *pay attention to labels*
Phylum: Cnidaria Class: Hydrozoa Genus: Obelia Body Form: Medusa
What phylum and class do these organisms belong to?
Phylum: Cnidaria Class: Scyphozoa
What phylum, class, and genus do these organisms belong to?
Phylum: Cnidaria Class: Scyphozoa Genus: Aurelia
What does it mean when an organism is diploblastic (like those in Phylum Cnidaria and Phylum Ctenophora)?
They have two true tissue layers (epidermis and endodermis/gastrodermis)
CNIDARIA DIGESTION/FEEDING:Describe the digestive process (e.g. incomplete and extracellular) and any specializations for feeding (e.g. cnidocytes, tentacles, etc.). A) Incomplete gut / gastrovascular cavity B)Complete (mount and anus) C)Use cnidocytes for prey capture D)Passive prey capture in some E)Intracellular digestion F)Extracellular digestion
A) Incomplete gut / gastrovascular cavity C) Use cnidocytes for prey capture D) Passive prey capture in some F) Extracellular digestion
CNIDARIA CLASSIFICATION: Only answer the phyla, classes, subclasses and other classification that you are responsible for knowing this week in lab. A)Phylum Cnidaria B)Class Porifera C)Phylum Annelida D) Class Scyphozoa
A) Phylum Cnidaria D) Class Scyphozoa
What structure(s) would help you determine whether a polyp of Obelia is a hydranth (feeding polyp) or a gonangium (reproductive polyp)? A) Presence of tentacles B) GVC C) Manubrium
A) Presence of tentacles Hydranths have tentacles, whereas gonangia do not.
CNIDARIA ORGANIZATION:At what level is the basic body plan organized? (e.g. cell, tissue, organ, etc.) A)Tissue level B) Organ level C)none of the above
A) Tissue level
Which are differences between the Cnidaria and the Ctenophora? A) Ctenophores have cnidocytes like cnidarians B) Ctenophores have eight "comb rows" of fused cilia along the sides of the animal used for movement, these are not present in cnidarians. C) Many cnidarians are completely sessile or with a life cycle that it's sessile, all ctenophores are also sessile
B) Ctenophores have eight "comb rows" of fused cilia along the sides of the animal used for movement, these are not present in cnidarians. Ctenophores have colloblasts, cnidarians have cnidocytes. Ctenophores have no alternation of generations and some think they have a complete gut. Many cnidarians are completely sessile or with a life cycle that it's sessile.
Which of these is a characteristic that differentiates fire corals and true corals? A)Fire corals are hydrozoans but have no cnidocytes, whereas true corals are anthozoans and have cnidocytes B) Fire corals are hydrozoans that have cnidocytes relatively visible to the naked eye, whereas the cnidocytes of anthozoan corals are not visible to the naked eye C)Fire corals and true corals are both corals from the Class Anthozoa, they are just different orders.
B) Fire corals are hydrozoans that have cnidocytes relatively visible to the naked eye, whereas the cnidocytes of anthozoan corals are not visible to the naked eye
Which of these are characteristics that can help distinguish between hydrozoan and scyphozoan medusae? A) In scyphozoans, the medusa stage is typically large and free-living, with the polyp stage small. B) Hydrozoan medusae generally have a muscular shelf, or velum, projecting inward from the margin of the bell. C) Schyphozoa medusae generally also have a muscular shelf, or velum, but it's projecting outward forming the arms.
B) Hydrozoan medusae generally have a muscular shelf, or velum, projecting inward from the margin of the bell. Velum is NOT found in scyphozoan.
If the phylogeny shown here is correct, what is the implication for the evolution of the diploblastic body (tissue level of organization) in animals? A) The diploblastic body evolved independently (separately) in Ctenophores and Cnidarians B) An ancestor of the Porifera had a more complex body but it was lost C) Either of the other two answers could be correct.
C) Either of the other two answers could be correct.
What class do these organisms belong to?
Class Hydrozoa
What class do these two organisms belong in?
Class Hydrozoa
How many rows of ciliated bands (combs) do ctenophores have?
Eight
True or False? Cnidarians have nervous tissue and sensory organs?
False - Lack nervous tissue and sensory organs - NO ORGANS - 'Nerve net' connective nerve cells and motor neurons - With light sensate ocelli
What is the common name of millepora?
Fire Coral
- Exist as individual polyp - Freshwater - Can reproduce sexually or sexually within same individual
Hydra littoralis
What are the representative animals of the Phylum Cnidaria Class Hydrozoa?
Hydra, Obelia, Fire Coral, Portuguese man-of-war
What are the four classes of cnidarians?
Hydrozoa, Scyphozoa, Cubozoa, Anthozoa
Do cnidarians have an incomplete or complete gut?
Incomplete gut - Rely on passive prey capture - Extracellular and intracellular digestion
What type of nervous system do ctenophores have?
Nerve net
- With a cube shaped dominant medusa stage - With four evenly spaced out tentacle or bunches of tentacles and well-developed eye - The Australian stinger Chironex fleckeri is among the deadliest creatures in the world, having caused human fatalities -- Tentacles up to three meters long -- One "sting" can easily kill a human, with death occurring in as little as three minutes
Phylum Cnidaria Class Cubozoa Characteristics
- Not true coral -- Hydrocorals - Nematocysts contain tentacles that protrude through surface pores -- Produce painful sting - Calcified skeleton is sharp and easily scrapes skin
Phylum Cnidaria Class Hydrozoa Genus Millepora Characteristics (Fire Coral)
- Polymorphic colony - Highly specialized polyps - Venom filled with nematocysts which paralyze and kills prey
Phylum Cnidaria Class Hydrozoa Genus Physalia Characteristics (Portuguese man o' war) - Physalia physalis
- Polyp is dominant stage - Most colonial - Produce a medusa stage - Velum ring and no oral arms (Exception is genus Hydra) - Medusa have very little mesoglea (looks like plastic bags) - Display sexual (medusae) and asexual (polyps) reproduction
Phylum Cnidaria Class Hydrozoa Characteristics
- True sea jelly - Thick layer of mesoglea - Medusa is the dominant life stage -- Very reduced polyp stage which buds off medusae - Largest in Lion's Mane -- 6ft in diameter, 100 ft long
Phylum Cnidaria Class Scyphozoa Characteristics
What Phylum does this organism belong in? What is the common name of this animal?
Phylum Ctenophora Comb Jellies
What phylum, class, and genus does this organism belong in?
Phylum: Cnidaria Class: Hydrozoa Genus: Hydra Hydra l.s. (longitudinal section) These photos are taking in succession moving down the slide to capture entire hydra l.s.
What is the phylum, class, and common name of this organism?
Phylum: Cnidaria Class: Anthozoa Common Name: Sea Fan
What is the phylum, class, and common name of this organism?
Phylum: Cnidaria Class: Anthozoa Common Name: Sea Fan (soft coral)
What is the phylum, class, and common name of this organism?
Phylum: Cnidaria Class: Anthozoa Common Name: Sea Pansy
What is the phylum, class, and common name of this organism?
Phylum: Cnidaria Class: Anthozoa Common Name: Sea Whip
What is the phylum, class, and common name of this organism?
Phylum: Cnidaria Class: Cubozoa Common name: Box jellyfish
What phylum, class, and genus does this organism belong in?
Phylum: Cnidaria Class: Hydrozoa Genus: Hydra Hydra c.s. (cross-section)
What is the phylum, class, genus, and common name of this organism?
Phylum: Cnidaria Class: Hydrozoa Genus: Millepora Common name: Fire Coral
What is the phylum, class, genus, and body form of this organism? *pay attention to labels*
Phylum: Cnidaria Class: Hydrozoa Genus: Obelia Body Form: Polyp Obelia is an example of a polymorphic colony
What is the phylum, class, genus, and body form of this organism?
Phylum: Cnidaria Class: Hydrozoa Genus: Obelia Body Form: Polyp Obelia is an example of a polymorphic polyp colony
What is the phylum, class, genus, and common name of this organism?
Phylum: Cnidaria Class: Hydrozoa Genus: Physalia Common name: Portuguese man o' war Physalia physalis
What phylum, class, and common name does this organism belong to?
Phylum: Cnidaria Class: Scyphozoa Common Name: Mangrove Jellyfish
What is the phylum, class, and common name of these organisms?
Phylum: Cnidaria Class: Scyphozoa Common Name: True sea
What phylum, class, and common name does this organism belong to?
Phylum: Cnidaria Class: Scyphozoa Common Name: cannonball jellyfish
What phylum, class, and genus do these organisms belong to?
Phylum: Cnidaria Class: Scyphozoa Genus: Aurelia (preserved specimens)
What is the phylum and common name of these organisms?
Phylum: Ctenophora Common Name: Comb Jelly
What is the phylum, class, and genus of this organism?
Phylum: cnidaria Class: hydrozoa Genus: hydra
What is the second stage of the reproductive cycle of Phylum Cnidaria Class Scyphozoa?
Scyphistoma (polyp)
What are the representative animals of the Phylum Cnidaria Class Anthozoa?
Sea Fan (soft coral), Sea Pansy, Anemone, and Coral (hard coral)
The sea pansy is a collection of polyps with different forms and functions. They're found in shallow waters on soft sandy bottoms, and can detach easily, are bioluminescent, and predated on by tiger nudibranchs. What would be the selective advantage of being bioluminescent?
Sea pansies are bioluminescent when they are touched or attacked by a predator. (Protection and reproduction)
Is the polyp form of a cnidarian sessile or motile?
Sessile
The nematocyst is an _____ inside the _____. When the small trigger on the [cell] is stimulated, an increase in _____ pressure within the cell causes the _____ to violently discharge, exploding out of the cell and releasing a long, hollow, threadlike _____.
The nematocyst is an organelle inside the cnidocyte. When the small trigger on the [cell] is stimulated, an increase in osmotic pressure within the cell causes the nematocyst to violently discharge, exploding out of the cell and releasing a long, hollow, threadlike filament.
What are differences between scyphozoan medusa with the medusa bud of obelia?
The scyphozoan have a thicker gelatinous mesoglea and tend to be much larger in size. They also stay in the medusa stage for almost their entire life instead of just for reproduction.
Why is the Mangrove Jellyfish called the upside-down jellyfish?
This scyphozoan is called the upside-down jellyfish because it rests upside down on the bottom of shallow areas in mangrove embayments. This allows sunlight to reach the symbiotic photosynthetic algae (zooxanthellae) it has in its mesoglea.
Which type of section does this image represent?
Transverse (cross) section
True or False? Cnidarians have a gastrovascular cavity (GVC).
True - Saclike and has only one opening which serves as both mouth and anus. - Functions as a
True or False? The Portuguese man-of-war is a pelagic colony of polymorphic zooids.
True Pelagic means relating to open sea
True or False? Cnidarians have a mesoglea.
True Mesoglea- non-cellular middle layer that provide support. between the two tissue layers - Not a tissue layer! - Jelly-like substance - Provides support for the body - Hydrostatic skeleton
In which tissue layer are the cnidocytes located?
epidermis
What type of symmetry do cnidarians have?
radial symmetry - no head, front, back - oral and aboral surfaces
Extracellular digestion
type of digestion in which food is broken down outside the cells in a digestive system and then absorbed
intracellular digestion
type of digestion in which food is digested inside specialized cells that pass nutrients to other cells by diffusion
How do cnidarians reproduce sexually?
- Both monoecious and dioecious - Some alternation of sexual and asexual stage
How do cnidarians reproduce asexually?
- Budding - Fission - Fragmentation - Pedal laceration (anemones)
CNIDARIA MOVEMENT/LOCOMOTION:What structures are used to help them move around their environment?(e.g. types of muscles, jointed legs, cilia, etc.). A)No structures used in locomotion B)Epitheliomuscular muscles C)Medusae swim by jet propulsion D)Hydrostatic skeleton
B) Epitheliomuscular muscles C) Medusae swim by jet propulsion D) Hydrostatic skeleton
CNIDARIA SYMMETRY:What type of symmetry is found in the basic body plan? (e.g. asymmetrical, radial. etc.) A)Asymmetry B)Radial symmetry C)Pentaradial symmetry D)Bilateral symmetry
B) Radial symmetry
What do the colloblasts of ctenophores do?
Cells that adhere to prey and bring to the mouth of the ctenophore
Do ctenophore have a complete or incomplete gut?
Complete gut
What is this picture showing? *pay attention to labels*
Cross-section of Phylum: Cnidaria Class: Hydrozoa Genus: Hydra
What is the fourth stage of the reproductive cycle of Phylum Cnidaria Class Scyphozoa?
Ephyra (immature medusa)
Ectoderm is the same as...
Epidermis
What type of skeleton do cnidarians have?
Hydrostatic skeleton (fluid held under pressure in a closed body) Muscles within the hydrostatic skeleton contract which creates pressure and moves the fluid-filled body
What is the name of this organism?
Portuguese man-of-war
Which type of section does this image represent?
Sagittal section
What are the representative animals of the Phylum Cnidaria Class Cubozoa?
Box jellyfish (Chironex)
What are the stinging cells of cnidarians called?
Cnidocytes
What is the function of the gastrozooid of Obelia?
Feeding polyp
What type of skeleton do ctenophores have?
Hydrostatic skeleton
Is the medusa form of a cnidarian sessile or motile?
Motile
Besides tentacles, what else do Phylum Cnidaria Class Scyphozoa have?
Oral arms
What is the collenchyme? Which phylum has a collenchyme?
Similar to mesoglea, but with muscle cells attached to it Phylum Ctenophora
Does Hydra reproduce sexually? Asexually? Or both?
Both Sexually through the production of eggs and sperm (gonads are visible on some individuals) Asexually through budding.
A specialized cell, containing cnidocyst, which is involved in capturing the prey in cnidarians
Cnidocyte
What is this a picture of?
Cnidocyte
- Each contains a stinging capsule/organelle (nematocyst) -- Either penetrate, fasten/coil, or adhere; some inject toxins - Hundreds of thousands may line exterior surface - Used for both prey capture and predator deterrent
Cnidocytes
Do cnidarians have cnidocytes or colloblasts?
Cnidocytes
Do ctenophores have cnidocytes or colloblasts?
Colloblasts
CNIDARIA REPRODUCTION:Describe the types of reproduction that occur in the group (e.g. sexual vs. asexual) and any other characteristics or specializations they may have for reproducing (e.g. monoecious vs. dioecious, fission, budding, etc.). A)Sexual only B)Monoecious only C)Dioecious only D) Both monoecious and dioecious E) Some alternation of sexual and asexual stage F) Asexual reproduction only
D) Both monoecious and dioecious E) Some alternation of sexual and asexual stage
Which type of section does this image represent?
Frontal section
Endoderm is the same as...
Gastrodermis
What Phylum do these animals belong in?
Phylum Cnidaria
What is the phylum, class, and body form of this organism?
Phylum: Cnidaria Class: Hydrozoa Body Form: Medusa
What is the phylum, class, and common name of this organism?
Phylum: Cnidaria Class: Anthozoa Common Name: Coral (hard coral)
What is the phylum, class, and common name of this organism?
Phylum: Cnidaria Class: Anthozoa Common Name: Sea Anemone
What is the function of the gonozooid of Obelia?
Sexually reproductive polyp
What is the third stage of the reproductive cycle of Phylum Cnidaria Class Scyphozoa?
Strobila (contains many immature medusae
Cassiopeia sp., commonly known as the "mangrove jellyfish" or "upside-down jellyfish" Could you think of a biological reason why they are usually found upside down?
This behavior provides sunlight to micro-algae living the tissue (endosymbionts known as zooxanthellae, similar to those occurring in corals) which provide nutrients to the host.
What specialized cells in cnidarians aid in capturing and subduing prey?
cnidocytes
Other Cnidarians
- Staurozoa (stalked jellyfish) - Myzozoa (micro-parasites) - Polypodiozoa (micro-parasites)
CNIDARIA SENSORY/NERVOUS:Describe the nervous system (i.e. ganglia, CNS, ventral nerve cord, etc.) and any sensory specializations found in the group (e.g. auricles, eyes, antennae, etc.). A)Nerve network B)Ocelli C)Cerebral ganglia D)Cephalization E)Light sensing organs
A) Nerve network B) Ocelli E) Light sensing organs
Which of the following is a characteristic of corals (anthozoans) that is also found in Porifera? A) neurons B) gastrovascular cavity C) filter-feeding D) nematocysts
C) filter-feeding
What is the first stage of the reproductive cycle of Phylum Cnidaria Class Scyphozoa?
Ciliated Planula Larva (free-swimming larvae)
How does excretion, circulation, and respiration work in cnidarians?
Diffusion
Why is the cannonball jellyfish named so?
This scyphozoan is called the Cannonball jellyfish because the mesoglea is so thick. To protect themselves from predators, juvenile jacks (a type of fish) position themselves about the stinking tentacles of this jellyfish.
What is this a picture of?
Undischarged nematocyst
Match the structure with its correct function.
d, b, a, c
What is a zooid?
polyp
What is the function of the gactylzooids of Obelia?
Defense polyp
What type of larvae do cnidarians have?
Planula larvae In other words, their larvae is ciliated and motile.
What type of symmetry do ctenophores have?
Radial symmetry
Select from the list which are similarities between Cnidaria and Ctenophora? A) Both are marine B) Both are diploblastic, with mesoglea C) Both have bilateral symmetry
A) Both are marine Both are marine, diploblastic, radial symmetry, and a branching gastrovascular cavity
CNIDARIA CIRCULATION:Describe the circulatory system (e.g. diffusion, open system, etc.). A)Diffusion B)Open circulatory system C)Closed circulatory system D)3-chamber heart E)4-Chamber heart
A) Diffusion
Place the following terms in their correct location on the figure.
A) transverse (cross) B) sagittal C) frontal D) dorsal E) ventral F) anterior G) posterior I) distal J) medial K) lateral
CTENOPHORA DIGESTION/FEEDING:Describe the digestive process (e.g. incomplete and extracellular) and any specializations for feeding (e.g. cnidocytes, tentacles, etc.). A) Incomplete gut / gastrovascular cavity B) Annal pores C)Use cnidocytes for prey capture D)Passive prey capture E)Use colloblasts for prey capture
B) Annal pores E) Use colloblasts for prey capture
Do cnidarians reproduce sexually or asexually?
Both, sexually and asexually
Why are cnidocytes located where they are located? A) Because they are used for digestion of prey, they must be located in the innermost tissue layer. B) Because they contain toxins, they must be located in the innermost tissue layer. C) Because they are used for defense and prey capture, they must be located in the outermost tissue layer.
C) Because they are used for defense and prey capture, they must be located in the outermost tissue layer.
How does excretion, circulation, and respiration work in ctenophores?
Diffusion
A specialized organelle inside a cnidocyte, consisting of an ejectable thread the causes a sting - Like mini-harpoons that can be ejected and used for anchorage, defense, and prey capture
Nematocyst
Do ctenophores have cnidocytes?
No However, some ctenophores collect them and use them for defense
What are differences between obelia and hydra?
Obelia - reproductive polyps - use a medusa to reproduce sexually - bud colonially Hydra - grow gonads and buds on side of body - only have one type of polyp
- Sessile with only a polyp stage (no medusa stage) - Exist as solitary individuals (e.g. anemones) or as true colonies (e.g. corals) - Most specialized and diverse of all cnidarians - All marine
Phylum Cnidaria Class Anthozoa Characteristics
What phylum does this organism belong in?
Phylum Ctenophora
What are the names of the two body forms that occur in the life cycle of a cnidarian?
Polyp and Medusa
Do ctenophores reproduce sexually or asexually?
Sexually Monoecious
True or False? Obelia is an example of a polymorphic polyp colony
True
What does polymorphism mean?
having more than one form Cnidarians often form colonies that consisting of many zooids (polyps). These zooids are often polymorphic and are specialized for certain functions: - Gastrozooid = feeding polyp -Gonozooid = sexually reproductive polyp -Gactylzooids = defense polyp
What type of organization (cell, tissue, etc.) cnidarians have?
tissue level (no organs)