Flashcards in Test 2 Deck (126):
Cteno = Greek for ______; phoros = _____
This group is often called the comb jellies or sea walnuts or sea gooseberries.
________ have eight "comb rows" of fused cilia arranged along the sides of the animal. These cilia beat synchronously in a wave pattern and propel ctenophores smoothly through the water. A beautiful iridescent rainbow pattern is produced by the diffraction of light passing between the cilia.
Some species move with a flapping motion of their lobes or undulations of the body. Many of these have two long tentacles, but some lack tentacles completely.
There are around 150 species of this Phylum; exclusively marine and live in all the world’s seas at all latitudes.
1 cm to 2 m in length. They are the largest of all animals that utilize the beating of cilia for locomotion.
They are planktonic – that is they drift with currents and only weakly swim (a few are bottom dwelling and creep around= benthic).
This phylum is entirely predacious – except for 1 parasitic sp. – eat small crustaceans, planktonic larvae of inverts (like oysters) & fish, may eat other ctenophores or cnidarians, some eat phytoplankton
Can live at the surface and all the way down to at least 3000 m
Most ___________ are: transparent, gelatinous (look like a cnidarian medusa), bioluminescent (due to chemical reactions which give off light), and fragile.
Because they are fragile, they are hard to capture with traditional sampling methods like trawling with nets. Until recently they were thought to be only moderately abundant but use of manned submersibles and SCUBA observations shows that they in fact make up a major portion of the planktonic biomass in a lot of areas.
What are the defining characteristics of Phylum Ctenophora?
Plates of fused cilia in rows (“combs” or “ctenes”)
Sticky prey-capturing cells (colloblasts)
Even though they are grouped with the Cnidarians in the Radiata, unlike the Cnidarians the _______ are “biradially” symmetrical, rather than radially.
Ctenophores are located between what on the cladogram?
Cnidarians and flatworms
Pleurobrachia sp. have 8 rows of _____ (comb rows; used for _______); move with mouth first – ciliar wave toward aboral end.
Many _________ have retractile tentacles and sometimes a tentacle sheath.
Which has a more extensively organized digestive system? Cnidarians or Ctenophore Pleurobrqchia
The mouth defines the oral pole of Pleurobrachia sp. (the other end of the animal is called _____)
The mouth of Pleurobrachia sp. consists of a narrow slit, which leads into the ______. Extracellular digestion begins in here.
After a Pleurobrachia's extracellular digestion of food, Partially digested food is then __________ by complex systems of gastrovascular canals. These canals are lined with ______ cells that complete digestion of food materials intracellularly.
distributed throughout the body, endodermal
The main g-v canal of C. Pleurobrachia ends in two small ____ ____; undigested wastes are released through the pores. This represents a step toward the evolution of a _______________.
anal pores, complete digestive tract
The Apical sense organ of C. Pleurobrachia does what?
regulates the ctenes
Colloblasts are on the _____ of Ctenophores. What do they help do?
tentacles, capture prey
Prey adheres to what of a colloblast cell?
_____ (Class _____) (Order _____) are unlike the other orders of Ctenophores. They lack any kind of tentacles at all stages of the life cycle. These vicious beasts have the habit of using a large mouth to consume other comb jellies with reckless abandon.
Beroe, (Class Nuda) (Order Beroida)
This group is benthic and
looks like a bit like sea slugs. Give Class and Order,
Phylum Platyhelminthes: the _______
This Phylum includes about 34,000 described species of free-living and parasitic worms – most are parasitic (more than 80%).
The free-living flatworms (Class ______) live in marine and freshwater benthic habitats and a few are terrestrial.
Which of the following are included in the Bilateria?
Diploblastic, Triploblastic pseudocelomates, Triploblastic acoelomates, Triploblastic eucoelomates
all except the Diploblasts
More than 99% of animal species belong to the _____ group.
The remarkable success of the bilateral animals can be attributed to the evolution of adaptations that helped with what 3 things?
1) food capture (e.g. the first hunters), 2) escape from predators, and 3) reproduction.
Where are flat worms on the cladogram?
Between ctenophores and Nemerteans
Phylum Platyhelminthes are ______ animals with: _____ symmetry, _____ tissue layers, _____, and ______ organs.
acoelomate, bilateral, 3 definite, cephalization, well-developed
Most Platyhelminthes are _________ _________. They usually cross-fertilize, self-fertilization is rare.
________ = loose group of cells with lots of different roles.
The presence of fibrous muscular mesoderm provides ______ _____ and allows for kinds of ______ that isn’t possible in the diploblastic radially symmetrical animals like the cnidarians.
structural support, locomotion
Fancy reproductive systems evolved in the _________ that made it possible for internal fertilization. Also the evolution of osmoregulatory organs were essential for the flatworms to invade freshwater – why?
playthelminths, to conserve salts, and excrete excess water in a hypotonic environment
What phylum am I?
gas exchange across body, lack circulatory and respiratory system, have a central nervous system, 2 nerve cords along side, no anus, dorsoventrally flattened body
_____________ lack a distinctive head, typically have suckers or hooks for holding on to hosts, have a tegument, and have complicated life cycles
Parasitic Flukes and Tapeworms
Why do Parasitic Flukes and Flatworms lack a distinctive head?
They are surrounded by their food and threats don’t come a particular direction inside the host. Energy has been redirected from making a head to other more important activities.
Why do Parasitic Flukes and Flatworms lack a ciliated epidermis?
instead they have a resistant covering called the Tegument that gives protection against host antibodies and enzymes (for those that live in guts) and it allows for the absorption of food across the body wall.
What Class am I? All are internal parasites – hosts are mostly vertebrates, Scolex – for attachment to host, Body is divided into reproductive segments (proglottids), may be 2000-4000 proglottids per tapeworm, loss of digestive tract.
What Class are tapeworms in?
Class Trematoda are the ______.
What calss is cylindrical or leaf shaped?
Class Trematoda eat ________ so they have kept a well-developed gut..
Around how many people may be infected with either Chinese live flukes or another species?
Where do adult Chinese liver flukes live?
in the bile ducts of humans causing serious medical problems
What is the species name of the Chinese liver fluke?
The common name for Fasciola hepatica is what?
Sheep liver flukes
Schistosoma is the scientific name for what?
Name this class. All parasitic in blood vessels of mammals/birds, requires two hosts – snail and vertebrate, no metacercaria or redia stage, Cercaria produced directly from sporocysts,
______ is a fairly sensitive creature and can spend a good deal of its time contracted inside its very flattened tortoise-like lorica. Like most rotifers, they are free-living. They feed and swim by means of their corona.
Pomphorhynchus is a __________.
All Acanthocephalans are ________!
And they have a coelom which is not lined by mesoderm – so its called pseudocoelom
The Rotifers & Acanthocephalans
The Rotifer phylum is between what, while the _____ are not included in our diagram.
Lophophorates and Nematodes, Acanthocephalans
The ______ and ________ used to be combined into one phylum called Aschelminthes but recent data, especially molecular, showed that this phylum was polyphyletic so they broke it up and gave each sub-group its own phylum.
Rotifers & Acanthocephalans
“Aschelminthes” had two main groups. What were they?
molting and non-molting
Acanthocephalans, Rotifers, 2 small phyla are _______ "Aschelminthes" and are now called Gnathifera.
The molting aschelminthes are related to ____ and are now called Cycloneuralia.
Advantages of having a body cavity (being a pseudocoelomate):
Opportunities for internal transport, Space for organ development, Hydrostatic support – important for movement & being able to protrude body parts
Phlyum Rotifera are known as what?
These are characteristics of what Phylum? 3 classes, ~ 2000 species, very high densities, important in food webs, live mostly in freshwater, most less than 0.5 mm, short-lived
Rotiferas have a corona which is.......
two lobes surrounded by beating cilia which look a bit like wheels that are rapidly rotating.
This phylum accounts for more than 50% of the zooplankton production in some freshwater ecosystems.
In their food webs, this phylum isn't only numerous but occupies several different trophic levels – most omnivores, some are carnivores, and some parasites.
About __% of Rotifers live in freshwater.
Rorifers move by _________. Some sessile species are....
swimming or crawling, permanently attached to freshwater plants.
Defining characteristics of what phylum:
the corona, a modified pharynx (mastax), have toes with adhesive glands
This class has one family with only 2 species. They are parasites on the gills of crustaceans.
This class lives in many different habitats (damp soil, wet moss, hot springs, Antarctic lakes, common in lakes/ponds, a few marine)
_____ is “suspended animation” during harsh conditions like drying, freezing, and/or high temperature, some make a cover and form a cyst which are cases where a rotifer has been rehydrated after 20 years of desiccation!
This species of rotifers is found only in the Antarctic. They reproduce in such huge numbers that they sometimes color the water red!
This is the only class of Rotifers with some sessile species.
All species in this Rotifer class make a thick protective cuticle called a lorica.
What class? 80% of all rotifers, free or sessile, lorica
What class of Rotifers is this?
widespread, free-living, tolerate extremes, cryptobiosis
This class is a small group of rotifers and are ectoparasites.
Phylum Acanthocephala is known has the ____ or _____ ______.
Spine or Thorn-Headed worms
Phylum? <1,200 species, all intestinal parasites of vertebrates, Arthropods sometimes required as intermediate hosts, Typically cylindrical and small
Eutely - Constant number of cells (which is species specific), No specialized respiratory structures, No circulatory system, Dioecious
Phylum Nemertea or the ______ are known as what?
Nemertines, Ribbion worms
There are a little less than 1200 described species of what phylum
The world's longest animal ever found was a Lineus longissimus which washed upon the shore of Scotland in the late 1800's. It measured 180 feet in length, beating out the Blue Whale for the title. What phylum does it belong to?
Most in this phylum are 3 to 20 cm long, often abundant but are difficult to identify so they are one of the least studied invertebrate groups, most are marine and crawl around on the bottom of shallow intertidal or sub-tidal areas or burrow into sediments, few are freshwater and a few terrestrial in moist tropical climates
In this phylum, most are carnivorous (eat small invertebrates like crustaceans and annelids (worms)), many apparently use chemical defenses to avoid being eaten; some species are thought to have bacterial symbionts that make neurotoxins that may serve as nemertean defense
This phylum's 'place' relative to other phyla: bilateral, triploblastic, protostomes, acoelomates – typically have been put in acoelomate group but that's controversial because recent studies of ultrastructure (seen with SEM) suggests that their blood vessels are modified coelomic spaces. Now placed in Lophotrochozoa group with flatworms, rotifers, molluscs, annelids, etc.
Where are Nemertines at on the chart?
Between Rotifers and Tardigrada
Most ____ are dioecious, some are protandric (1st male, then female), usually external fertilization, most have larval stage, some can reproduce asexually by fragmenting or fission.
Phylum Nemertea (ribbon worms)
There are __ classes of ribbon worms based on what?
2, presence or absence of stylets and position of mouth relative to proboscis.
________ is one of the most diverse groups of animals on the planet, with at least 50,000 living species (and more likely around 120,000 to 200,000). It includes such familiar organisms as snails, octopuses, squid, clams, scallops, oysters, and chitons.
This phylum ranges in size from 20-meter-long giant squid to microscopic aplacophorans, a millimeter or less in length, that live between sand grains.
The study of living molluscs is known as ______. The study of mollusc shells is called _____.
How many classes are in Phylum Mollusca?
Class Polyplacophora: Phylum? Includes?
Class Aplacophora: Phylum? Includes?
Mollusca, worm-like animals
Class Monoplacophora: Phylum? Includes?
Class Gastropoda: Phylum? Includes?
snails, slugs, limpets
Class Bivalia: Phylum? Includes?
scallops, clams, mussels
Class Scaphopoda: Phylum? Includes?
Class Cephalopoda: Phylum? Includes?
squids, octopuses, nautilus
What is the biggest class of Phylum Mollusca? 2nd biggest?
Which class of molluscs is extinct? Which living class is not found in the fossil record?
All of the following are what? Finelined Pocketbook, Georgia Pigtoe, Southern Fatmucket, Three-horned Wartyback, Southern Toesplitter, Alabama Heelsplitter, Pistolgrip, Southern Rainbow
species of mussels
Freshwater Mussels are known as what?
Number of species of Unionidae in the US? Worldwide? % in US?
300, 1,000, 30%
What is the US ranked in world diversity of freshwater mussels? freshwater snails?
Number of freshwater snail species in the US? worldwide? % in US?
600, 4,000, 15%
What are some threats to freshwater mussels?
dams, pollution, exotic species (zebra mussels)
Watershed is how many acres?
The Conasauga ranks ___ nationally for the number of federally threatened and endangered species in a single watershed.
Two fishes, a snail, and a crayfish are endemic to the Conasauga watershed, and the last populations of three mussel species.
How many species of fish are found in the Conasauga River (about __ are native).
How many species of mussels are found in the Conasauga River (down from __ historically).
How many species of crayfish are in the Coosa River Basin?
snails (down from __ historically)?
18, 25, 32
How do mussels get a fish to carry their young? How do Epioblasma do it?
Luring them, grab on to the fish and spit larvae inside fish's mouth
What class of molluscs include squids, octopods, and Nautilus?
Name my class. Active/predatory swimmers, Closed circulatory system, Foot modified to form arms/tentacles/and siphon, Have large brain in cartilaginous cranium, All are marine and have a radula and ctenidia
How do Molluscs with no shell avoid being eaten?
be fast, have good eyes, ink sac, chromatophores, photophores
The following are key adaptions of what?
Cephalization, A central nervous system, A coelom (of course, flatworms don’t have this), A tube-within-a-tube body plan, Compartmentalization of the body
Phylum Platyhelminthes: the flatworms
In bilateral symmetrical animal evolution of a head evolved along with unidirectional movement & a more active lifestyle than that of radially symmetrical animals. In these animals concentration of sense organs and nerve cells (simple brain) are found at the _____ end.
Increases effectiveness of bilateral animal: to actively _______ and to ____________.
find food, shelter, mates; detect enemies
The feather-duster worms and black fly larvae are both bilateral animals that filter food from water. Can you tell me why the feather-duster worm has radial-like feeding structures, while the black fly has bilateral (2-dimensional) feeding structures?
The feather-duster worms live in a marine benthic environment, while black fly larvae attach to rocks in streams.