TEST 1 Flashcards
What are the what are the four classes of Cnidarians?
Anthozoans
Hydrozoans
Scyphozoa
Cubozoa
What are the two subclasses of anthozoans?
Hexacorallia and octocorals
Which class of cnidarian only has a polyp form?
Anthozoans
Corals and anemones belong to which class of which phylum
Phylum cnidarian, class anthozoan
How are to two subclasses of anthozoans different in terms of symmetry?
Hexacorallia - 6 part symmetry
Octocoralia - 8 part symmetry
Which subclass of anthozoan do the stony corals belong to? How about soft corals?
Stony corals = hexacorallia
Soft corals = octocorallia
What is the ecological importance of anthozoans?
Dinoflagellates + symbiotic relationship Biodiversity hot spot - 25% marine life 3D habitat Food for other animals Shelter Mutualism w anemones
Explain a symbiotic relationship that corals (class anthozoan) have with dinoflagellates
Dinos = photosynthetic
Provide food for corals
How does coral bleaching involve dinoflagellates?
When corals under stress, dinos get ejected from corals and corals lose their food source
Explain how other animals have mutualism with anemones (class anthozoan)
Mucus on fish so their can live in anemones (finding nemo)
Crabs that put anemones on the backs of their shell for extra protection
Ex. Boxer crabs
Gorgonian corals come from with subclass of anthozoans? What is a property they have that makes them a soft coral?
Subclass octocorallia
Proteinaceous bodies with calcareous spicules in their mesoglea endoskeleton
What class do the siphonophores belong to?
Class hydrozoans
Some hydrozoans are more dominantly medusa form, some are more dominantly polyp form… this makes them what type of group?
Disparate group
Freshwater cnidarians belong to what group?
Hydrozoans
What is an example of a hydrozoan that is fresh water nad exclusively polyp form?
Hydra
What is an example of a medusa form cnidarian in the hydrozoan class that is found off the coast of NS?
Aequorea victoria
Siophonophores are usually found where? Are they independent animals or do they live in colonies?
Deep sea
Colonial animals
Do hydrozoans tend to live by themselves or in colonies?
Colomies
Some parts lf a hydrozoan are meant for swimming, while other parts are meant for food capture, while other parts are meant for eating… hydrozoans have what ?
Polymorphism
What class are the true jellies in?
Class scyphozoa
Name everything you can about the scyphozoa class of cnidarians
Dieocious (separate sexes)
Large oral lobes extend from mouth
Strobilation and reproduction (scyphistoma —> stack of strobila —> ephyra (tiny jellies, flower shape) —> big true jellies with either male of female sex
Explain the strobilation and reproduction of class scyphozoa (true jellies)
Larvae settle anywhere and then become
- schyphistoma
- duplicate through mitosis - Stack of strobila (jelly stack)
- break off + mature + grow bigger - Ephyra - tiny baby flower shaped jellies, either female or male
What class would a species that looks like a jelly, is dominantly in the medusa form, has tentacles on each corner of its face and has an eye that can sometimes be image forming?
Class cubozoa
Manh cnidarians exhibit 2 body forms… this means what?
They have polyps and medusa forms
Is a cnidocyte a cell or an organelle? What about a cnidae?
Cnidocyte = cell Cnidae = organelle
What is the fourth big spit?
Phylum ctenophora
What are ctenes?
They are comb rows of cilia that comb jellies, in phylum ctenophora, have
How many ctenes do comb jellies have?
8 ctenes
What type of symmetry do ctenophora have? How about cnidarians?
Ctenophora = bi radial symmetry
Cnidarians = radial symmetry
Ctenophora have colloblast cells on their tentacles… why?
To help with food capture because they’re sticky / adhesive
What type of ctenophore decimated a black sea ecosystem in the 90s?
A mnemiopsis ctenophore
How many ctenes to ctenophores have? How do they swim / move?
8 ctenes
Swim mouth forward, move via beating cilia
Largest animal to move via cilia
What are the two forms or ctenophores and how do they differ?
Mnemiopsis - eats plankton and things in water column via colloblasts on tentacles
Beroe form - eats other ctenophores, doesn’t have colloblasts, just has a giant mouth
Where does the colour in ctenophores cmoe from? Shy are the deep sea sepcies red?
Light refracts off the tightly packed ctenes / comb rows
Red so predators can’t see them, red is the first colour to disappear in the deep sea
What are the four classes of poifera?
Class calcarea
Class homoscleromorpha
Class hexactinellids
Class demospongiae
Which class and which phylum has spicules made of calcium carbonate and has examples of all 3 canal systems?
Phylum poifera
Class calcarea
What class of poifera is the newest class that was named in 2012 and used to be classified under demospongiae?
Class homoscleromorpha
What kind of spicules does class homoscleromorpha of phylum poifera have?
Spicules that are all the same form
Which class of poifera have 6 rayed silica spicules that make a glass lattice?
Class hexactinellida
What class do 80% of sponges come from?
Demospongiae
Where do freshwater sponges classify?
Demospongiae
What body form do sponges in class demospongiae usually have?
Leuconoid body form
How do poiferas feed?
Intracellular digestion (phagocytosis)
Flagellated collar cells help them get food
Carnivorous sponges don’t have choanocytes, they have tiny hooks that help catch prey
Do poiferas have sexual or asexual preproduction
Both
How do poiferas sexually reproduce
Sperm comes from choanocytes that release into water column —> another sponges takes them up
Eggs / oocytes come from archaocytes
How do sponges asexually reproduce?
Via budding fragmentation or dormant gemmules
Why are dormant gemmules are good type of reproduction for freshwater sponges?
They have variable living conditions
Gemmules stay dormant until conditions are right, then the wake up and germinate
What are dormant gemmules?
Type of asexual reproduction for poiferas
Internal buds packed with archeocytes (where eggs come from), surrounded by thick layer of spicules
What are symbioses that we see with poiferas?
Microbial
- green algae and photosynthesis
- Nutrient cycling
Humans + sponges
- first food item harvested from ocean
- Medications and pharmaceuticals
- fibre optics - technology and industry
What is a flat animal but is multicellular, was thought to be made of only one species (the trichlplax adhaerons). Has cilia, no body cavity and has 5-6 body cells? What phylum?
Phylum placozoa
What are the two body forms of cnidarians?
Polyp and medusa
What are the unique stinging cells that cnidarians have called?
Cnidocyte
What is the jelly layer in cnidarians called?
Mesoglea
How many classes of cnidarians are there? Can you name them all?
5 classes
- anthozoans
- hydrozoans
- Scyphozoa (true jellies)
- cubozoa
- staurozoa (didn’t talk about them though)
Cnidarians made two big evolutionary jumps… what were they?
They have tissues and radial symmetry!
What level of organization do cnidarians have?
Cells that carry -out functions
Don’t have organs yet
Why are cnidarians considered dipoblastic?
Because they have tissues
How did the cnidarians become dipoblastic?
Cells made hollow ball which underwent gastrolation
Hollow ball ivaginated
Diffrentiated into endoderm (gut) and ectoderm (skin)
What kind of symmetry to cnidarians have?
Radial
What dipoblastic properties do cnidsrians have? Name each tissue layer / body cavity
Endoderm = gastrodermis / gut
Ectoderm = epidermis / skin
Mesoglea = jelly NOT TISSUE
Gastrovascular cavity
What is the diffrence between the medusa and polyp form of cnidarians?
Polyp = sessile, anemone form
Medusa = swimming, jellyfish form, use contractions to swim
The Portuguese man-o-war is a great example of what…
Polyp form cnidarian of class hydrozoan
How to the cnidarains exhibit polymorphism/ polyp form?
All the polyps are genetically identical but can carry out different functions = polymorphism
Ex. Portuguese man-o-war
How do cnidarians reproduce?
Alternating generations between polyp and medusa forms
Polyps asexually make baby medusas which are sexually reproducing
How do medusa forms of cnidarians reproduceto make new polyps
Hint - planula
Make sperm and egg through meiosis
Gametes make PLANULA - these settle and make new polyps
How cnidarians move? Do they have muscles like us?
Epitheliamuscular cells in their tissue which has nerves
nerve nets / mesh of nerves in tissue that signals contractions
Explain how the cnidocyte, the cnidae, the nemotocyst and the cnidocil work together
Cnidocyte is the stinging cell
Cnidae is an organelle/capsule in the cell containing the nematocyst
Nematocyst is an organelle w stinging venom
Cnidocil is a hair like trigger
Cnidae discharges nematocyst when anincrease of hydrostatic pressure is detected and nematocyst breaks off
97% of all named species are what?-
Invertebrates
What are the 5 major basal splits of animals groups
Porifera Placazoa Cnidarians Ctenophores Bilateria
Phylum porifera… do they have true tissues?
Nope, don’t have true embryonic tissues
Explain the aquiferous system of porifera / sponges
Oscula = out S[pongocoel = inside sponge, lined with collar cells Ostia = in
What is a choanocyte?
Sticky collar cell with flagellum
Line the spongecoel
Food capture, waste, move water efficiently
What are the the three types of cana; systems?
Asconoids
Synconoids
Leuconoids
What are the differences between the three types of canal systems
Asconoid = inside of cell lined with choanocytes, only in class calcarea
Synconoid = folded niner layers w collar cells lining the folds, only in class calcarea
Leuconoid - collar cells line inside chamber, msot sponges this form, all classes, icnreases SA + SIZE of sponge
Which canal system increases SA + size pf s[ponge by having the collar cells line the inside chambers?
Leuconoid
What two type of cells help make a sponge?
Choanocyte and archaeocytes
What are archaeocytes?
Totipotent cells in sponges, found in mesophyl of sponge (btw inner and outer sponge layer)
Can become many different types of cell (feeding, spicule making, spongin making, reproduction)
What are archaeocytes important for sponges?
Because they don’t have tissues, so they rely on these totipotent cells to provide different functions
The collagen fibres in sponges are called what?
Spongin
The spicules of sponges are made of what?
Silica or calcium carbonate
What are the four classes of porifera?
Homoscleromorpha
Calcarea
Demospongae
Hexactinellida
In the geologic time scale, what is the order from cambrian to cretaceous?
Camels often sit down carefully, perhaps their joints creak
Cambrian Ordovician Silurian Devonian Carboniferous Permian Triassic Jurassic Cretaceous
When you say taxa (taxon singular) what do you mean?
All the species under that hierarchy
Example taxa animalia - all the animals
Who developped the binomial nomenclature?
Carolus linnaeous
What ia convergent evolution?
How things got the same related trait but through unrelated lineages, for a common purpose
Ex eyes of cephalopod and vertebrates - both image forming but from different ancestors
Traits that come from the same evolutionary origin are called what?
Homologous structures
What is a clade?
All animals in clade shafe a derived trait / character
A clades that exhibit monophyly show what?
Most recent common ancestor of all descendants
A clades that exhibit paraphyly show what?
Most recent common ancestor and some but not all of its descendants
- reptiles exclude birds, but they should have them because they have recent ancestor
A clades that exhibit polyphyly show what?
No recent common ancestor
No evolutionary origin (homoplasy)
What are the 5 key transitions in animal architecture
Levels of organization (complexity)
Symmetry
Body cavity
Developmental traits
Segmentation
What are the levels of organization in order
Protoplasmic - single cell Cellular Cell tissue Tissue Organ
Why wouldn’t animals exhibit protoplasmic level of organization?
Because animals are multicellular
What is the cellular level ov organization?
Cells that have different functions
Ex. Choanoflagellates (in protists)
What is the cell tissue level of organization/
Specific cells work together to have specific functions - TEAMWORK!
Porifera, placozoa
Welcome in the metazoans
What is seen in the tissue level of organization?
Basement membrane forms - connects cells for more coordination
Ex. Nerve net in cnidarians
What is seen in the organ level of organization?
Tissues work together to make organ with special function
What animal at the organ level of organization is the simplest ?
Flatworms
Bilateral symmetry is tied to cephalization - what is cephalization?
Diffrentiation of head from rest of the body, sense organs in head region
In order to have true body cavities, you need to have three things… what are they?
Endoderm, ectoderm and mesoderm
Triploblastic animal
Are cnidarians and ctenophores able to have true body cavities?
No, because they are diploblastic (only have endo and ectoderm)
How do body cavities form?
Cell make hollow ball called BLASTULA w fluid filled centre called BLASTOCOEL
folds inward making GASTRULA w BLASTOPORE hole - starts out as mouth leading to gut
What are the three types of body cavities that can form if you are triploblastic animal?
Acoelomate
Pseudocoelomate
Eucoelomate
What are the two types of acoelomate body cavities?
Ones with mesodermal germ layer that fills the blastocoel
Onces without mesodermal germ layers
For the phyla nematoda, the mesoderm cells line the outer edge of the blastocoel, making two body cavities - what type pf body cavity plan is this and what are the two body cavities made?
Pseudocoelomate
Makes a gut cavity and blastocoel partially lined with mesoderm
In the eucoelomate body plan - the mesoderm splits into a true body cavity call a what? Why is it a true body cavity?
Coelom
True body cavity because lined completely by mesoderm making two body cavities - gut and coelom
What was a key transition in metazoan evolution that allowed for the orgnas to grow independently off the body wall and increased the size of triploblastic animals?
Coelom body cavities
What are the development divisions for triploblastic animals?
Protostome or deuterotome
Bilateral animals are divided into two groups - what are they
Proteostomes and deuterostomes
What has embryos with spinal cleavage, the first blastopore hole becomes the mouth, and they form coelom by splitting off pockets f mesoderm?
Protostomes
What are the 2 main groups of protostomes?
Lophotrochozoa
Ecdysozoa
The lophotrochozoa form of protostomes have either ______ structure or a ________
Lophophore feeding structure or a trochophore larvae
This form of protostome forms a solid, monophyletic group based on one derived characterisitc - ability to molt (ecdysis). What form is it?
Ecdysozoans
The other main group besides the protostomes are the deuterostmoes… this developmental grouping is based on what?
The blastopore became the anus
Mouth formed from second hole in embryonic gastrula
What is biodiversity?
Measure of all the organisms in a particular location
What are you measuring when you measure biodiversity?
Abundance (# of species) and richness (types of species)
The Simpson diversity index emphasizes what?
Does diversity increase/decrease with abundance / dominance ?
Abundance
Diversity dec w abundance
The shannon-weiver index emphasizes what?
Does diversity increase or decrease w abundance?
Richness
Decreases
What are the three embryonic germ layer that triploblasts have and what does each layer do
Ectoderm - nervous system + sense organs
Endoderm - makes the gut
Mesoderm - blood
To have a true body cavity you need to be…
Triploblast / have a mesoderm
What are the three types of body cavities
Acoelomate
Pseudocoelomate
Eucoelomate
What type of body cavity does the mesoderm line the inner body cavity, leaving the organs unorganized?
Acoelomate
What type of body cavity is fluid filled, with the mesoderm lining the inside of the extoderm, not connecting to the organs?
Pseudocoelomate
What type of body cavity to all deuterstomes have, where the mesoderm connects to organs + gut and allow compartmentalization?
Eucoelomate
What are three indicative characteristics of a bilatarian animal?
Triploblasts
True body cavity
Cephalization
The new phylum made in 2016 with 4 new species of worms that were more acoelomorpha is called what
Xenacoelomorpha - new phylum
Are acoelomorpha more marine of frehswater?
Marine
Acoelomorpha don’t have two things… they have a syncytial digestive vacuole in replacement of these two things… what are they?
No anus and no gut
Acoelomorpha use what for orientation? (Early sensory systems)
Statocyst
The platyzoa inckude the phylum platyhelmnithes. How many parasitic classes and non-parasitic classes are there under this phylum?
Parasitic = 3 classes
Non-parasitic = turbellarians
What kind of body plan to platyhelminthes have?
Acoelomate (parenchyma) and dorso-ventrally flattened
What are flame cells and which phylum are they characteristic of?
Platyhelminthes have flame cells
Excretory and osmoregulation
What are the protonephridia made of in platyhelminthes?what do they do?
Flame cells + tube cells
Remove excess water
Turbellarians is a clsas under the phylum…
Platyhelminthes of the bilaterians
Turbellarians have ciliated epidermis. The epidermis contains ___________ - these help make the worm distasteful to predatory by discharging slime/mucous
Rhabdites
Tubellarians - a key feature of their skin and muscle is their attach and detach systems that is opwered by what?
Dual gland adhesive organs
How do turbellarians eat / feed?
Scavengers + predators
Extracellular + intracellular digestion
Blind ended gut
Do turbellarians have cephlization?
Yes
Turbellarians - a key feature is their nervous system / cephalization. What are the following structures used for; Statocyst Rheoreceptors Ocelli Auricles
Statocyst - orientation
Rheoreceptors - currnts
Ocelli - eyes
Auricles - ears
Turbellarians - what has ear like lobes with chemoreceptors and tactile cells?
Auricles
How do turbellarians reproduce? Is it asexual, sexual or both? Female and mald sex organs? Are they diecious?
Both sexual + asexual
Sexual - penis fencing, hermaphroditism, internal fertilization with copulation
What are some distinct features of parasitic Platyhelminthes?
Skin - non ciliated epidermis, syncytial cells, HAVE NEODERMATA
Digestion through absorption
Nervous systems - minimal cephalization
Reproduction - diff among classes
Do both parasitic and non-parasitic platyhelminthes have neodermata?
No just parasitic
The parasitic flukes are in which class of playtyhelminthes?
Class trematoda
What is the life cycle of the parasitic digenea flukes of class trematoda?
Two hosts
Eggs fertilized in poop
Hatch in intermediate host
Intermediate host is the first host, asexual amplification
Swimming form infects vertebrate
Young flukes infect final host to mature and reproduce sexually
What are two common digenean flukes
Liver flukes
Blood flukes
- swimmers itch
How many host does the class monogenea have in its life cycle? (Platyhelminthes)
One host
What class of platyhelminthes is ectoparasitic and live on the skin and gills of fish?
Class monogenea
What class of Platyhelminthes do tapeworms belong to?
Class cestoda
What is the scolex used for in class cestoda (tapeworms)?
Attach to the intestinal wall of host
Do tapeworms have true segmentation?
No they have proglottids - conveyer belt of reproductive units
How do tapeworms (phylum platyhelminthes, class cestoda) eat?
Absorption, no digestive organs
Use microtriches to absorb nutrients
Explain the reproductive factories of tapeworms using the following terms; strobila, uterine pore, scolex
Young grow from scolex - attached to intestinal wall of host (why you don’t rip a tapeworm)
Eggs come out the uterine pore
Strobila is the main part of the body that is asexually reproduced, but matures to make female and male parts
How do people usually get infected by tapeworms?
Fertilized eggs in GRAVID PROGLOTTIDS - shelled larvae that come out of poop
Undercooked meat/fish can have cysts in the muscle
write out the key transition for phylum xenacoelomorpha
Organization - organ Symmetry - bi lateral Body cavity - acoelomate Development - triploblast (basal) Segmentation - no
Write out the key transitions for phylum platyhelminthes
Organization - organ Symmetry - bi lateral Body cavity - acoelomate Development - triploblast (protostome - locomorpha) Segmentation - no
Being bi lateral means…
Triploblast
Have embryonic mesoderm
Can be protostome or deuterstome
How do protostomes and deuterstomes differ?
Embryonic development
0
Deuter - blastopore becomes the anus
Proto - blastopore becomes the mouth
Are tubellarians dioecious?
No
Do tapeworms have an intermediate host? (Phylum platyhelminthes, class cestoda)
No
Protostomes - lophotrochozoans are called…
Trochozoans
The first great lophotrochozoans was…
Annelids
The big step that lophotrochozoans took in body plans was…
Segmentation
The annelids (lophotrochozoans) have ture segmentaion making them…acoelomate, pseudocoelomate, eucoelomate
Eucoelomate
Annelids have metamerism. What is this?
Body has repeated units that are separated by septa
How do lophotrochozoans move?
Hydrostatic skeleton made by fluid filled coelom
Longitudinal muscles - contract body shortens + expands
Circulare muscles contracts - body narrows + lengthens
Contractions at different rhythms for different muscles
How do lophotrochozoans use their coelom for movement
Helps make the hydrostatic skeleton
Ringed worms and bristle worms belond to which phylum?
Annelida
What are two defining annelid features?
Setae and paraopdia
What are setae? (Distinct in annelids)
Chintinous epidermal bristles
Help burrow, move
What are parapodia?
Paddle like feet
Swimming, respiration, crawling
What is a basic body plan for annelids
2 part head (prostomium and peristomium)
Metamerism (lots of segments)
Terminal pygidium
Epidermis covered in non-chitinous cuticles
Which class of annelids has the motile polychaetes
Errantia
How do polychaetes in class errantia reproduce?
Dioecious (both female and male sexes)
External fertilization
TROCHOPHORE LARVAE !!!!!
Class sedentaria has what type of polychaetes generally
Tube dwelling / burrowing
What worms are under the class sedentaria that used to be their own classes?
Oligochaetes (earthworms)
Hirudinians (leeches)
Pogonophora (beardworms)
Echiuran worms
How do worms / polychaetes in class sedentaria get food
Filter feeding or deposit feeding
Cilia and mucus + food grooves on tentacles help trap food
What are the old pogonophora called now under class sedentaria?
Sibloglinidae
Say everything you can about class siboglinidae
Beard worms Used to pogonophora Use chemauto\rophic bacteria Live in hydrothermal vents No digestive system, rely on symbiotic relationships for food + absorption
What used to be called phylum echniura is now class what under the phylum sedentaria… what kind of worms are these?
Echiuridae
Spoon worms
Why are they called spoon worms (sedentaria - echiuridae)
They have a flat, extensible proboscis (elongated tube part attached to the mouth used for feeding)
Sedentaria - clitellata have thpes of polychaetes… what are they
Hirudinidae
Oligochaetes
Are all polychaetes under sedentaria - clitellata hermaphroditic?
Yes
How do polychaetes under sendentaria-clitellata reproduce?
No trocophore larvae, just direct development
How would you classify an earthworm?
Annelida (phylum), class sedentaria - clitellata, oligochaete
How do earthworms reproduce
Simultaneous sperm exchange
Eggs in clitellum
Clitellum makes cocoon for eggs that fertilizes and slides off + new worm born
Is the clitellum always or only sometimes seen in earthworms?
Always seen in earthworms
What would you classify leeches under?
Phylum annelida, class sedentaria - clitellata, hirudinidae
Is the clitellum always visible in leeches?
No, only visible during reproduction
How does the visibility of the clitellum differ in earthworms and leeches
Earthworms - clitellum always visible
Leeches - only visible during reproduction
What lost their secondarily lost their setae, has true metamerism but a fixed number of segments, has posterior and anterior suckers, no septa but a coelom made of thick connective tissue and has a powerful pharynx used for blood sucking/carnivorous?
Leeches (annelida, sedentaria - clitellata, hirudinidae)
What is an unranked type of peanut worms that is sometimes its own phylum?
Sipuncula
What do you know about the unranked peanut worms sipuncula?
No segmentation and no setae
Ciliated introverted feeding tentacles
Trochophore larvae unites them with the greater lophotrochozoans
What unites the sipuncula peanut worms with the lophotrochozoans ?
Trochophore larvae unites them with the greater lophotrochozoans
Name the 5 key transitions for phylum annelida
Organization - organ Symmetry - bi-lateral Body cavity eucoelomate Development - triploblastic Segmentation - yes
