Test 2 Flashcards
Cteno = Greek for ______; phoros = _____
comb, bearing
This group is often called the comb jellies or sea walnuts or sea gooseberries.
Phylum Ctenophora
________ 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.
Phylum Ctenophora
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.
Phylum Ctenophora
There are around 150 species of this Phylum; exclusively marine and live in all the world’s seas at all latitudes.
Phylum Ctenophora
1 cm to 2 m in length. They are the largest of all animals that utilize the beating of cilia for locomotion.
Phylum Ctenophora
They are planktonic – that is they drift with currents and only weakly swim (a few are bottom dwelling and creep around= benthic).
Phylum Ctenophora
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
Phylum Ctenophora
Can live at the surface and all the way down to at least 3000 m
Phylum Ctenophora
Most ___________ are: transparent, gelatinous (look like a cnidarian medusa), bioluminescent (due to chemical reactions which give off light), and fragile.
Phylum Ctenophora
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.
Phylum Ctenophora
comb bearing
Phylum Ctenophora
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
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.
ctenes, locomotion
Many _________ have retractile tentacles and sometimes a tentacle sheath.
Pleurobrachia sp.
Which has a more extensively organized digestive system? Cnidarians or Ctenophore Pleurobrqchia
C. Pleurobrachia
The mouth defines the oral pole of Pleurobrachia sp. (the other end of the animal is called _____)
aboral
The mouth of Pleurobrachia sp. consists of a narrow slit, which leads into the ______. Extracellular digestion begins in here.
pharynx,
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?
sticky material
_____ (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,
Class Tentaculata
Order Platyctenida
Phylum Platyhelminthes: the _______
flatworms
This Phylum includes about 34,000 described species of free-living and parasitic worms – most are parasitic (more than 80%).
Platyhelminthes
The free-living flatworms (Class ______) live in marine and freshwater benthic habitats and a few are terrestrial.
Turbellaria
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.
Bilateria
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.
simultaneous hermaphrodites
________ = loose group of cells with lots of different roles.
Parenchyma
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
Platyhelminth
_____________ 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.
Class Cestoda
What Class are tapeworms in?
Cestoda
Class Trematoda are the ______.
flukes
What calss is cylindrical or leaf shaped?
Trematoda
Class Trematoda eat ________ so they have kept a well-developed gut..
hosts’ tissue
Around how many people may be infected with either Chinese live flukes or another species?
20 million
Where do adult Chinese liver flukes live?
in the bile ducts of humans causing serious medical problems