General Bio II Exam (Worms)- Pointer

jelly-like layer below pinacocytes in Porifera

mesohyl

specialized pinacocyte, tubelike, contractile which regulate water circulation and make pathways for water moving through the body wall in Porifera

porocytes

Produce both sperm and egg in the same animal body.

monoecious

separate sexes, in separate individuals

dioecious

internal capsules of amoeboid cells that resist freezing and drying-Porifera

gemmules

specialized cells used in defense, feeding, and attachment. Cnidaria.

cnidocytes

cnidocytes contain ?, which discharge tubes armed with spines and toxins in Cnidaria

nematocysts

small sac surrounding a CaCO3 statolith to detect tilting in Cnidaria

statocyst

located on tentacles, they are adhesive cells. In Phylum Ctenophora-Sea Walnuts and Comb Jellies

colloblasts

spongy mass of undifferentiated cells around the viscera, muscles, or epithelial cells in addition to gastrodermis and epidermis. In Triploblastic Acoleomate Body Plan

parenchyma

all female reproduction, diploid eggs yield more females. Common in Rotifers

parthenogenesis

2 body types, males smaller than females. In Nematoda

dimorphic

periodic shedding and replacement of body covering

molting

unload toxins by biting, stinging, injecting

venomous

unload toxins when eaten, etc

poisonous

male and female reproductive organisms housed together

monoecious

male and female are separate sexes

dioecious

characteristics of what phyla?

Aquatic and mostly marine, 9,000 species, asymmetrical or superficially radially symmetrical, no tissues or organs and loosely interdependent cells

Porifera

thin and flat cells living in the outer surface of a sponge. Changes shape of a sponge. Some are specialized into porocytes. These are in Porifera.

pinacocytes

amoeboid cells move about in the mesohyl, a jelly-like layer below the pinacocyte. Specialized for reproduction, secreting skeletal elements, transporting and storing food, forming rings around openings. These are in Porifera.

mesenchyme

lie below the mesohyl and line the inner chamber, flagellated cells create water currents. Filters food particles. These are in Porifera.

choanocytes

needle-like spikes in a variety of shapes. CaCO3 and silica

spicules

fibrous protein made of collagen

spongin

adults are sessile and attached to a substrate and dependent on water currents. Occurs in what phylum

Porifera

Porifera Body Form

simplest and least common, Ostia lead directly to spongocoel, choanocytes draw water in with flagella. In Ostia and out terminal osculum. What body form?

ascon

Porifera Body Form

folded walls, water enters by dermal pores, pores from incurrent canals leads to radial canals, choanocytes line the radial canals and push water to the spongocoel, 1 terminal osculum

sycon

Porifera Body Form

water enters through dermal pores and flows through branched incurrent canals, leading to the choanocyte lined chambers, excurrent canals lead away from chambers, no spongocoel, multiple oscula. Most common

leucon

as internal surface area increases, they are more _________________, and there are more ____________________

complex, choanocytes

greater flow=__________________ efficiency

greater

Porifera Maintenance Functions

filter feed on __________________ matter. ____________________ trap food, mesenchyme cells transport it. Nitrogenous wastes diffuse from cells directly into water and there is no nervous system.

organic, Choanocytes

Reproduction of Porifera

most are monoecious and produce sperm and egg. Sperm and eggs exit from osculatory to fertilize in the surrounding water. Some regenerate asexually when broken into pieces

Characteristics of Cnidaria-Jellyfish, Hydra, Anemones, and Corals

radial symmetry, gastrovascular cavity-blind cavity with a single opening (mouth), diploblastic tissue level of organization. The epidermis and gastrodermis are separated by the mesoglea

This specialized cell occurs in cnidaria, used for defense, feeding, and attachment in epidermis and gastrodermal cells.

Cnidocytes

Body Form of Cnidaria

asexual and sessile. Cylindrical with mouth surrounded by tentacles

polyp

Body Form of Cnidaria

dioecious (separate sexes) and free swimming, mouth and tentacles facing downward

medusa

organism experiences both polyp and medusa stages

alternation of generations

Cnidaria Maintenance Functions

gastrovascular cavity-

used for digestion, exchange of gases, metabolic wastes, discharge of gametes (through mouth)

Cnidaria Maintenance Functions

feed on small crustaceans, digestion partially extracellular, and partially intracellular. Gas and waste from simple diffusion. Water-filled gastrovascular cavity serves as a hydrostatic skeleton. Contractile cells work against water to give the body shape.

Cnidaria movement

polyps-

move slowly by somersaulting, gliding, walking on tentacles

Cnidaria Movement

medusa

swim and float. Water and wind utilized for movement.

Nervous system of Cnidaria

most primitive in animalia. 2D nerve net (web of cells), under the epidermis under the mesoglea

Reproduction of Cnidaria

most are dioecious, fertilization outside body.

Reproduction of Cnidaria

planula

ciliated, free-swimming larvae that attaches to a substrate and develops into a polyp

Characteristics of Hydra (class of Cnidaria)

common freshwater cnidarian that hangs from floating plants. Hydra has no medusa stage and polyp reproduces both sexually and asexually. Mostly marine but only class with freshwater characteristics. Polyp and medusa stages in most. Nematocysts in epidermis, external fertilization, mesoglea mostly acellular. Obelia is a common marine hydrozoan forms a colony

Characteristics of Scyphozoa

entirely marine, polyp and medusa stages in most. Medusa is the dominant stage. Mesoglea contains amoeboid cells, cnidocytes in gastrodermis and epidermis. Display negative photo-taxis

Characteristics of Cubozoa

related to jellyfish, all marine, cube-shaped medusa with stinging tentacles

Characteristics of Staurozoa

stalked jellyfish, all marine, polyps with oral ends that look like medusa. Crawling, non-ciliated larvae

Characteristics of Anthozoa

sea anemones, corals. Marine. largest cnidarian class. All attached polyps, medusa stage absent.

What is the largest cnidarian class

anthozoa

What phyla is described?

Marine, 90 species, gelatinous (similar to jellyfish), swim using 8 comb rows, diploblastic, and possibly triploblastic. Briradial symmetry, branched gastrovascular canal system, nerve net, statocysts, bioluminescent, monoecious, external fertilization, tentacles

Phylum Ctenophora-Sea Walnuts, Comb Jellies

Feeding and Reproduction of Phylum Ctenophora

feed on plankton, small invertebrates. Some have tentacles with colloblasts others have no tentacles, dioecious with external fertilization

Sponges are the most _________________ animals, among the oldest on record

primitive

Cnidarians arose early, primitive _________________ may have been ancestors

anthozoans

Distant relations between ___________________ and ____________________

ctenophores, cnidarians

protostomes that do not molt

lophotrochozoa

Protostomes that molt

ecdysozoa

Triploblastic Acoelomate Body Plan

5 phyla-

acoelomorpha, Platyhelminthes, Nemertea, Gastrotricha, Cycliophora. All are lophotrochozoans

Triploblastic Acoelomate Body Plan

spongy mass of undifferentiated mesoderm cells around the viscera, muscles, or epithelial cells. Functions: skeletal support, nutrient and oxygen storage, transport, motility

parenchyma

Acoelomorpha characteristics

small, flattened, marine worms recently split from the Platyhelminthes. Very primitive digestive and organ systems. Free-living. Asexual reproduction or monoecious

Flatworms

Phylum Platyhelminthes

Phylum Platyhelminthes (flatworms) Characteristics

usually flattened dorsoventrally, unsegmented or strobliated (tapeworms), organ systems, 4 classes, distinct head w/ centralization of the nervous system, blind-sac body incomplete gut and mouth is the only permanent opening most are monoecious

Class Turbellaria-Phylum?

Platyhelminthes

Planarians

Class Turbellaria, Phylum Platyhelminthes

Class Turbellaria, Phylum Platyhelminthes Characteristics

3,000 species, free-living bottom dwellers in freshwater and marine environments, ciliated epidermis in direct contact with the environment, locomotion by cilia and muscle undulations

Class Turbellaria (Phylum Platyhelminthes), Digestion

most carnivores, feeding on small invertebrates, incomplete digestive tract (no anus). Digestive cavity varies from rare to highly branched. Pharnyx is the ingestive organ.

Class Turbellaria (Phylum Platyhelminthes), Gas Exchange

no circulatory or respiratory system, gases exchanged through the body wall, most metabolic wastes are removed by diffusion

Class Turbellaria (Phylum Platyhelminthes), Osmoregulation

marine turbellarians are near osmotic equilibrium and freshwater turbellarians must osmoregulate

Protonephridia network of tubules along the length of the body in parenchyma tissue.

Flame cells-tiny hollow enlargements that beat cilia to create negative pressure

Class Turbellaria (Phylum Platyhelminthes), Nervous system

vary from nerve nets to nervous system with nerve cords. Tissue concentrated in cerebral ganglion or a pair of primitive brains.

Respond to stimuli.

Auricles (sensory lobes) may project from side of the head with chemoreceptors and ocelli (eyespots)

Dense group of nerve-cell bodies

ganglion

Class Turbellaria (Phylum Platyhelminthes), Reproduction

Asexual: transverse fission divides into anterior and posterior animal------->monoecious

Sexual: reciprocal sperm exchange between animals, eggs deposited in cocoons, larvae resemble adults

Phylum Platyhelminthes (flatworms), Class Monogenea, characteristics (monogenetic fluke)

>1,000 species, marine and freshwater, ectoparasites of fish, have a posterior attachment organ-----> opisthaptor. Monoecious but cross fertilize, and develop into free-swimming larvae (monogenetic fluke)

Monogenea

group of parasitic flatworm flukes that have only one host during the life cycle

Class Trematoda (Phylum Platyhelminthes) (flukes:parasitic worms), characteristics

>10,000 species, parasitic and of considerable economic and medical importance. Body flat and oval or elongated. Epidermis has a tegument-continuous layer of fused cells efficient at absorbing nutrients and resisting immune system of hosts.

2 subclasses of Trematoda or flukes

Aspidogastrea and Digenea

tegument

continuous layer of fused cells efficient at absorbing nutrients and resisting immune system of hosts.

Class Trematoda (Phylum Platyhelminthes) (flukes:parasitic worms), digestive system

attach with 2 suckers oral (anterior) and acetabulum (mid-body), anterior mouth, muscular pumping pharynx, blind pouches called cecae, feed on host cell and fragments

Class Trematoda (Phylum Platyhelminthes) (flukes:parasitic worms), life cycle

2 body forms adult and larval, at least 2 hosts, adults live in blood stream, digestive tract or visceral organs of a host (vertebrate)

Eggs produced sexually exit and hatch in water. Ciliated larvae swim to find intermediate hosts. Asexual reproduction takes place in intermediates and second larvae leave intermediates and are consumed by or penetrate hosts

Class Cestoda (Phylum Platyhelminthes)

tapeworms

Class Cestoda (Phylum Platyhelminthes), characteristics

3,500 species, specialized endoparasites in digestive system, lack mouth and digestive system use body wall instead, consist of repeating units--------> Proglottids

Class Cestoda (Phylum Platyhelminthes), body regions

1) scolex- holdfast structure containing system of suckers and hooks

2) neck-immature proglottids

3)stroblia-series of proglottids, which produce eggs when mature

Class Cestoda (Phylum Platyhelminthes), structural adaptations

Tapeworms live in stable environments. The tegument is similar to flukes and is the only means of absorbing nutrients and enzymes from a host. Reduced nervous system-nerve mass in scolex with lateral cords. Simple protonephridia system

Class Cestoda (Phylum Platyhelminthes), reproduction

monoecious with testes and ovaries in proglottids. Sperm and eggs are produced at different times, so fertilization occurs between different proglottids. The eggs accumulate in gravid proglottids. These then break away, pass out in feces, and are consumed by intermediate hosts where they penetrate muscles

Taeniarhynchus saginatus

beef tapeworm

pork tapeworm

Taenia solium

fish tapeworm

Diphyllobothrium latum

bore into bloodstream where they encyst and become cysticerci or bladder worms

beef and pork tapeworms

invade human muscle tissue causing cysticercosis

pork tapeworm

2 intermediate hosts-crustaceans and fish

fish tapeworms

Ribbon worms

Phylum Nemertea

Phylum Nemertea (Ribbon Worms), characteristics

~900 species of free-living marine worms, extendable proboscis for feeding, carnivores and feed on segmented worms or crustaceans, ingest invertebrates, more evolutionary advanced than flatworms.

have protonephridia, cerebral ganglion, and nerve cords line flatworms. Fluid filled sac functions like a primitive coelom. Complete digestive tract with anus and closed circulatory system, dioecious, external fertilization, ciliated larvae

Phylum Nemertea (Ribbon Worms), characteristics

Phylum Gastrotricha

~500 species, fresh water, and marine, small, occur in sediment. A complete digestive system with mouth, pharynx, intestine, and anus. Acoleomate but removed from other phyla because of different protonephridia.

No larval stage, act as mini adults

Marine Form of Phylum Gastrotricha reproduce

monoecious and sexually

Freshwater form of Phylum Gastrotricha reproduce

using parthenogenesis

Phylum Cycliophora

symbions

Phylum Cycliophora characteristics

most recently described phylum, live on mouths of lobsters (commensalism), dioecious

Pseudocoleomates

Aschelminthes

Pseudocoleomates (Aschelminthes) body plan

several phylum, polyphyletic, 2 lophotrochoazoan phyla, 5 ecdysozoan phyla

Pseudocoleomates (Aschelminthes) characteristics

fluid filled pesudocoelom (false body cavity), distinct body cavity but lacks mesenteries (membranes) and peritoneal linings, serves in circulation, digestion, and locomotion (hydrostatic skeleton). All have a protective non-cellular cuticle

Most have a muscle pharynx, adhesive glands, complete digestive tract, dioecious, microscopic, and vary from freshwater, parasitic, and marine

Pseudocoleomates (Aschelminthes) characteristics