zoology journal

8/2/2019 Zoology Journal

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De La Salle Health Sciences Institute

Dasmarinas, Cavite

Phylum Cnidaria, Platyhelminthes, Nematoda, Annelida, Mollusca

ZOOLOGY JOURNAL

(Background, Life Cycle, Medical Application)

Miguel, Vecher Denise C.

BSPT 1-1

Mrs. Minerva R. Basilio

February 16, 2012


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PHYLUM CNIDARIA

Cyanea capillata

Background

Lion's mane jellyfish, or Cyanea capillata, has

made a sensational appearance in literature,

most notably in Sherlock Holmes's 'The

Adventure of the Lion's Mane.' However, lion's

mane jellyfish is nowhere close to as dangerous

as it is made out to be in popular culture. The

lion's mane jellyfish can attain enormous size. In

fact, the largest Lion's Mane jellyfish is not

merely the largest species of jellyfish in the

world; it is the largest animal in the world. The

one specimen of Lion's Mane which was found in

Massachusetts Bay in 1870 was over 7 feet in

diameter and its tentacles were longer than 120

feet in length. However, the bell of the Artic

Lion's Mane is known to be able to grow up to 8

feet in diameter, and their tentacles can acquire

the length of 150 feet. That is much longer than blue whale, which is generally thought

to be the largest animal in the world.

Lion's mane jellyfish are highly variable in size. While the largest lion's mane jellyfish

are found in the northernmost peaks of the Arctic Ocean, the size of the jellyfish

diminishes as you travel further south. The jellyfish found between 40 degrees latitude

and 42 degrees latitude is amongst the smallest varieties of lion's mane jellyfish. On an

average, the body of the lion's mane jellyfish usually only grows up to 8 feet in diameter.

Similarly the length of the tentacles also decreases as the size itself begins to diminish.

The color of the lion's mane jellyfish is also dependent on its size. The largest

specimens of the lion's mane jellyfish are a dark crimson in color. As their size reduces,

the color becomes lighter until it is light orange or tan.


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Life Cycle

Most jellyfish undergo two distinct life history stages

(body forms) during theirlife cycle. The first is

thepolypoidstage. After fertilization and initial

growth, a larval form, called theplanula, develops.

The planula is a small larva covered with cilia. It

settles onto a firm surface and develops into

a polyp. The polyp is generally a small stalk with a

mouth surrounded by upward-facing tentacles like

miniatures of the closely related anthozoan polyps

(sea anemones and corals), also of the phylum

Cnidaria. This polyp may be sessile, living on the

bottom or on similar substrata such as floats or

boat-bottoms, or it may be free-floating or attachedto tiny bits of free-living planktonor rarely, fish or

other invertebrates. Polyps may be solitary or

colonial. Most are very small, measured in

millimeters. They feed continuously. Certain Box

Jellyfish species sleep on the sea bed in shallow

water.

Medical Application

A sting from the lion's mane jellyfish is not only incapable of causing human deaths; all itdoes is cause an itchy rash and mild burning sensation. Although the rash can be

painful for sensitive individuals and the toxins in the venom may cause an allergic

reaction, the stings from a lion's mane jellyfish can be treated by application of vinegar.
http://en.wikipedia.org/wiki/Biological_life_cyclehttp://en.wikipedia.org/wiki/Polyphttp://en.wikipedia.org/wiki/Planulahttp://en.wikipedia.org/wiki/Ciliumhttp://en.wikipedia.org/wiki/Polyphttp://en.wikipedia.org/wiki/Anthozoahttp://en.wikipedia.org/wiki/Sea_anemonehttp://en.wikipedia.org/wiki/Coralhttp://en.wikipedia.org/wiki/Sessility_(zoology)http://en.wikipedia.org/wiki/Biological_life_cyclehttp://en.wikipedia.org/wiki/Polyphttp://en.wikipedia.org/wiki/Planulahttp://en.wikipedia.org/wiki/Ciliumhttp://en.wikipedia.org/wiki/Polyphttp://en.wikipedia.org/wiki/Anthozoahttp://en.wikipedia.org/wiki/Sea_anemonehttp://en.wikipedia.org/wiki/Coralhttp://en.wikipedia.org/wiki/Sessility_(zoology)


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Physalia physalis

Background

Anyone unfamiliar with the biology of the

venomous Portuguese man-of-war wouldlikely mistake it for a jellyfish. Not only is itnot a jellyfish, it's not even an "it," but a"they." The Portuguese man-of-war is asiphonophore, an animal made up of acolony of organisms working together.

The man-of-war comprises four separatepolyps. It gets its name from the uppermostpolyp, a gas-filled bladder, or pneumatophore, which sits above thewater and somewhat resembles an old

warship at full sail. Man-of-wars are alsoknown as bluebottles for the purple-bluecolor of their pneumatophores.

The tentacles are the man-of-war's secondorganism. These long, thin tendrils canextend 165 feet (50 meters) in length below

the surface, although 30 feet (10 meters) is more the average. They are covered invenom-filled nematocysts used to paralyze and kill fish and other small creatures. Forhumans, a man-of-war sting is excruciatingly painful, but rarely deadly. But bewareeven dead man-of-wars washed up on shore can deliver a sting.

Muscles in the tentacles draw prey up to a polyp containing the gastrozooids ordigestive organisms. A fourth polyp contains the reproductive organisms.

Man-of-wars are found, sometimes in groups of 1,000 or more, floating in warm watersthroughout the world's oceans. They have no independent means of propulsion andeither drift on the currents or catch the wind with their pneumatophores. To avoidthreats on the surface, they can deflate their air bags and briefly submerge.

Life Cycle

Hydroid colonies are usually dioecious, which means that they have separate sexes - all

the polyps in each colony are either male or female, but not usually both sexes in the

same colony. In some species, the reproductive polyps, known as gonozooids bud off

asexually-produced medusae. These tiny, new medusae (which are either male or

female) mature and spawn, releasing gametes freely into the sea in most

cases. Zygotes become free-swimming planula larvae or actinula larvae that either

settle on a suitablesubstrate (in the case of planulae), or swim and develop into another

medusae or polyp directly (actinulae).
http://en.wikipedia.org/wiki/Hydroidhttp://en.wikipedia.org/wiki/Dioecioushttp://en.wikipedia.org/wiki/Gametehttp://en.wikipedia.org/wiki/Zygotehttp://en.wikipedia.org/wiki/Planulahttp://en.wikipedia.org/wiki/Substrate_(biology)http://en.wikipedia.org/wiki/Hydroidhttp://en.wikipedia.org/wiki/Dioecioushttp://en.wikipedia.org/wiki/Gametehttp://en.wikipedia.org/wiki/Zygotehttp://en.wikipedia.org/wiki/Planulahttp://en.wikipedia.org/wiki/Substrate_(biology)


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The medusa stage, if present, is the

sexually-reproductive life cycle

phase (that is, in hydrozoan

species that have both polyp

and medusa generations).

Medusae of these species ofHydrozoa are known as

"hydromedusae". Most

hydromedusae have shorter life

spans than the

largerscyphozoan jellyfish.

Some species of

hydromedusae release

gametes shortly after they are

themselves released from the

hydroids (as in the case offire

corals), living only a few hours,while other species of

hydromedusae grow and feed in

the plankton for months,

spawning daily for many days before their supply of food or other water conditions

deteriorate and cause their demise.

Medical Application

The toxin of Physalis is dangerous to humans, causing excruciating pain and

sometimes leading to death. Long after the death of Physalis the toxin can remainpotent and toxic, so they should always be handled with extreme care whenencountered.
http://en.wikipedia.org/wiki/Scyphozoahttp://en.wikipedia.org/wiki/Fire_coralhttp://en.wikipedia.org/wiki/Fire_coralhttp://en.wikipedia.org/wiki/Planktonhttp://en.wikipedia.org/wiki/Scyphozoahttp://en.wikipedia.org/wiki/Fire_coralhttp://en.wikipedia.org/wiki/Fire_coralhttp://en.wikipedia.org/wiki/Fire_coralhttp://en.wikipedia.org/wiki/Plankton


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Chironex fleckeri

Background

Chironex fleckeriis the largest of the cubozoans

(collectively called box jellyfish), many of which may carry

similarly toxic venom. Its bell grows to about the size of a

basketball, and trails four clusters of 15 tentacles trailing

from each of the four corners of the bell. The pale blue bell

has faint markings and viewed from certain angles it bears

a somewhat eerie resemblance to a human head orskull.

Since it is virtually transparent, the creature is nearly

impossible to see in its habitat, posing particular danger to

swimmers.

Life Cycle

The life cycle of a sea wasp corresponds

to the Chirodropid life cycle which exhibits

seasonal alternation of generations

between freshwater and saltwater. In themarine environment, a male adult

medusa releases sperm to fertilize the

eggs of an adult female medusa. After

fertilization, the embryo develops into a

free swimming planula larvae in

freshwater. Once the larvae reaches an

area with suitable resources, it settles

down onto the sediment and transforms

into a polyp. Rather than transforming

into a schyphistoma, this polyp producesother polyps that bud off and transform

into the adult medusa
http://en.wikipedia.org/wiki/Box_jellyfishhttp://en.wikipedia.org/wiki/Tentaclehttp://en.wikipedia.org/wiki/Skullhttp://en.wikipedia.org/wiki/Box_jellyfishhttp://en.wikipedia.org/wiki/Tentaclehttp://en.wikipedia.org/wiki/Skull


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Medical Application

Chironex fleckeriis best known for its extremely powerful and occasionally fatal sting.

The sting produces excruciating pain accompanied by an intense burning sensation,

and the venom has multiple effects, attacking the nervous system, heart, and skin at the

same time. While an appreciable amount of venom (contact from about ten feet or threemetres of tentacle) needs to be delivered in order to have a fatal effect on an adult

human, the potent neurotoxic venom is extremely quick to act. Fatalities have been

observed as little as four minutes after envenomation, notably quicker than any snake,

insect or spider. Occasionally a person swimming who gets stung will undergo cardiac

arrest or drown before they can even get back to the shore or boat.

If a person does manage to get to safety, treatment must be administered urgently.

Dousing a sting with vinegarimmediately inhibits any nematocysts which have not been

activated, whereas rubbing a sting or dousing with alcohol can encourage nematocysts

to activate. After dousing with vinegar, rescue breaths and CPR may be required; forless serious stings, treatment with ice packs and antihistamines is an effective method

of pain relief. Adhering tentacles should be removed carefully from the skin using

protected hands or tweezers. An antivenom to the Box Jellyfish's sting does exist. After

the immediate treatment described above, it must be administered quickly. Hospitals

and ambulance services near to where the jellyfish live possess it, and must be

contacted as soon as possible. The jellyfish's venom is so powerful, however, that even

if the victim does get to safety and have the immediate treatment given and contact the

ambulance, they may die before the ambulance reaches them.
http://en.wikipedia.org/wiki/Sting_(biology)http://en.wikipedia.org/wiki/Vinegarhttp://en.wikipedia.org/wiki/CPRhttp://en.wikipedia.org/wiki/Antivenomhttp://en.wikipedia.org/wiki/Sting_(biology)http://en.wikipedia.org/wiki/Vinegarhttp://en.wikipedia.org/wiki/CPRhttp://en.wikipedia.org/wiki/Antivenom


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PHYLUM PLATYHELMINTHES

Eurylepta californica

Background

Body greyish-white with white border andnarrow mid-dorsal white line; withirregular black lines crisscrossing dorsalsurface. With a dark mark (blackproximally, red distally) at the bases ofthe large marginal tentacles.

Found in the low rocky intertidal (andsubtidal). Relatively rare, sometimes

found floating upside down on thesurface film in tidepools (especially on early morning low tides). One individual wasfound with its pharynx inserted into the tunicate Clavelina huntsmani, apparently feedingon the tunicate.

Life Cycle


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Parasitic flatworms are also known as flukes. They start life as eggs that are passed out

in the faeces of birds such as oystercatchers. If eaten by a mudflat snail, or whelk, the

eggs hatch and the larvae multiply by budding. The tiny fluke larvae leave their whelk

hosts and invade another shellfish, cockles. The larvae accumulate in the foot of

cockles, preventing them burrowing into the mud to escape predation. The stranded

cockles are eaten by oystercatchers. Once inside the bird, the flukes mature and

produce fertilised eggs, and the cycle begins again.

Medical Application

Infection by a parasitic flatworm called a fluke. The infection can occur in the digestive

tract as well as other organs such as the liver. A person can become infected by

consuming uncooked fish, plants or animals from waters that are fluke-infested. The two

main types of flukes that can affect humans are liver flukes and lung flukes which canresult in diseases such as Schistosomiasis, fascioliasis, opisthorchiasis and

paragonmiasis.


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Maiazoon orsaki

Background

The diagnostic characters for this

species are the presence of twomale gonopores posterior to the

pharynx and the presence of

three to five female gonopores.

The transparent light brown or

cream background with a thin

white median line is also a

diagnostic character for this

species.

Elongate oval body, raised medially with marginal ruffles and slightly taperedposteriorly. Transparent light brown or cream background with a thin white median line

starting anteriorly to the cerebral eyespot and ending just prior to the posterior margin.

An indistinct marginal band, intensifying into orange-brown with a narrow black rim. A

big cerebral cluster of eyes and a simple pharynx anteriorly located. Two male

gonopores posterior to the pharynx and three to five female gonopores equidistant,

located posterior and well separate from the male pores.

Life Cycle

Cestodes (tapeworms) and

trematodes (flukes) have

complex life-cycles, with

mature stages that live as

parasites in the digestive

systems of fish or

land vertebrates, and

intermediate stages that infest

secondary hosts. The eggs of

trematodes are excreted from

their main hosts, whereas

adult cestodes generate vast

numbers ofhermaphroditic,

segment-like proglottids which

detach when mature, are excreted and then release eggs. Unlike the other parasitic
http://en.wikipedia.org/wiki/Vertebratehttp://en.wikipedia.org/wiki/Hermaphroditichttp://en.wikipedia.org/wiki/Proglottidhttp://en.wikipedia.org/wiki/Vertebratehttp://en.wikipedia.org/wiki/Hermaphroditichttp://en.wikipedia.org/wiki/Proglottid


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groups, the monogeneans are external parasites infesting aquatic animals, and their

larvae metamorphose into the adult form after attaching to a suitable host.

Medical Application

A central component of all multicellular life is the ability of cells to divide -- and divideevenly. Before a cell divides, it has to assemble two exact copies of its DNA and thenmake sure that DNA sorts evenly into the two separate halves as they pinch off. Manyhealth problems arise from cells losing this ability.

A hallmark of cancer, for instance, involves abnormalities in this division. Tumor cellsoften duplicate extra pieces of DNA. Certain forms of childhood mental retardation arealso marked by abnormal divisions, which cause the loss of large pieces of DNA,leading to development problems in certain brain structures.Centrosomes have been seen as animals' ultimate evolutionary fix for this problem.

Plants and fungi don't have them, but animals have had centrosomes in their cells, aslong as there have been animals. These structures were thought to play a central role incell division -- laying down track-like spindles onto which the cells sort their dividingDNA. Centrosomes were seen as so important to cell division that all animals wereassumed to have them. The discovery that at least one animal doesn't came quiteunexpectedly.


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Cycloporus venetus

Background

Small polyclad, purple-bluecolour, with yellow

marginal band and

tentacles and a

longitudinal white line

in the middle of the

back. 2 cm. Found

along the external

reef. It can be

associated withcolonial ascidians

(withAtriolumrobustum, withOxycorynia fascicularis), probably its food.A certain similitude withPseudoceros bifurcus, the latter having amore complex longitudinal line.

Life Cycle
http://www.seadb.net/en_Lesser-urn-ascidian-Atriolum-robustum_273.htmhttp://www.seadb.net/en_Lesser-urn-ascidian-Atriolum-robustum_273.htmhttp://www.seadb.net/en_Stalked-green-ascidian-Oxycorynia-fascicularis_292.htmhttp://www.seadb.net/en_Pseudoceros-bifurcus_131.htmhttp://www.seadb.net/en_Lesser-urn-ascidian-Atriolum-robustum_273.htmhttp://www.seadb.net/en_Lesser-urn-ascidian-Atriolum-robustum_273.htmhttp://www.seadb.net/en_Stalked-green-ascidian-Oxycorynia-fascicularis_292.htmhttp://www.seadb.net/en_Pseudoceros-bifurcus_131.htm


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Medical Application

Anthelmintics are drugs that are used to treat infections with parasitic worms. This

includes both flat worms, e.g., flukes and tapeworms and round worms, i.e., nematodes.

They are of huge importance for human tropical medicine and for veterinary medicine.

The World Health Organization estimates that a staggering 2 billion people harbor

parasitic worm infections. Parasitic worms also infect livestock and crops, affecting food

production with a resultant economic impact. Also of importance is the infection of

domestic pets. Indeed, the companion animal market is a major economic consideration

for animal health companies undertaking drug discovery programs.


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PHYLUM NEMATODE

Aphelenchoides ritzemabos

Background

Aphelenchoides ritzemabosi(Black currant nematode, Chrysanthemum foliar

nematode, Chrysanthemum leaf nematode, Chrysanthemum nematode) is a plant

pathogenic nematode

Life Cycle

The length of life-

cycle of

Aphelenchoidesritzema-bosi is 10

to 13 days. Each

female lays about

twenty-five to thirty-

five eggs in

compact groups.

The eggs take 3 to

4 days to hatch and

the larvae 9 to 10

days to reachmaturity.

Fertilisation and

egg laying occur

chiefly at the

boundary between

the discoloured and

green portions of the leaf. The amount of free water inside the infested leaf is

determined by weather conditions; eelworm activity in the leaf is, consequently, mainly

confined to periods when there is rain or heavy mists. Early stages of chrysanthemum

eelworm cannot resist desiccation as well as late stages. 95 per cent of late stage

larvae and adults emerge from leaves immersed in water for 2 days compared with 12

per cent early stage larvae. Few small larvae invade leaves or migrate up the plant.

Adults, unlike larvae, are able to swim because of the greater propulsive forces they

generate. Adults and possibly fourth stage larvae are responsible for spread of

infestations.


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Medicinal Application

The survival of Aphelenchoides

ritzemabosi in soil and leaves was

studied at four chrysanthemum

nurseries and in the laboratory. No

nematodes were recovered from

nursery soils after the 4th April. In

wet soil inoculated with

eelworms or infested leaves the

eelworms died rapidly and none was recovered after 17 weeks except in frozen soil at -

5 C when 0.3% were alive after 15 months. In dry soil kept at 5 C, 10% wererecovered after 15 months. Higher temperatures (18 and 25 C) reduced survival time.

Chrysanthemum eelworms in dried leaves kept at 25 C died within 2 years but at 4 C

and 7 C, 33% and 8% respectively were alive after 3 years when all active stages were

recovered.


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Nacator americanus

Background

Necator americanus is a species ofNecator. It is a

class within the phylum Nematodes and commonlyknown as New World hookworm. It is a parasitic

nematode worm that lives in the small intestine of

hosts such as humans, dogs, and cats. It is

responsible forNecatoriasis. Since Necator

americanus andAncylostoma duodenale (also known

as Old World hookworm) are the two most common

human hookworms, they are usually discussed together as hookworm infection. They

differ only in geographical distribution, structure of mouthparts, and relative size.

Life Cycle

This worm starts out as an

unembryonated egg in the

soil. After 2448 hours under

favorable conditions, the eggs

become embryonated and

hatch. This first juvenile stage

1 is known as rhabditiform.

The rhabditiform larvae grow

and molt in the soil,

transforming into a juvenile

stage 2. The juvenile stage 2

molts once more until

reaching the juvenile 3 stage,

which is also called filariform;

this is also the infective form.

The transformation from

rhabditiform to the filariformusually takes 5 to 10

days. This larvae form is able

to penetrate human skin,

travel through the blood

vessels and heart, reaching the lungs. Once here, they burrow through the pulmonary

alveoli and travel up the trachea, where they are swallowed and are destined for the
http://en.wikipedia.org/wiki/Necator_(nematode)http://en.wikipedia.org/wiki/Necatoriasishttp://en.wikipedia.org/wiki/Ancylostoma_duodenalehttp://en.wikipedia.org/wiki/Necator_(nematode)http://en.wikipedia.org/wiki/Necatoriasishttp://en.wikipedia.org/wiki/Ancylostoma_duodenale


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small intestine. This is where they mature and reproduce into adults by attaching

themselves to the intestinal wall, causing an increase of blood loss by the host. The

eggs end up on the soil after leaving the body through the feces. On average, most

adult worms are eliminated in 1 to 2 years. N. americanus life cycle only differs slightly

fromA. duodenale. N. americanushas no development arrest in immune hosts and it is

necessary for it to migrate through the lungs.

Medical Application

When adult worms attach to the villi of the small intestine, they suck on the host's blood,

which may cause abdominal pain, diarrhea, cramps, and weight loss that can lead to

anorexia. Heavy infections can lead to the development of iron-deficiency and

hypochromic microcytic anemia. This form of anemia in children can give rise to

physical and mental retardation. Infection caused by cutaneous larvae migrans, a skin

disease in humans, is characterized by skin ruptures and severe itching.


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Clonorchis chinesis

Background

Clonorchis sinensis, the

Chinese liver fluke, is a

human liverfluke in the

class Trematoda,

Phylum Platyhelminthes.

This parasite lives in

the liverof humans, and

is found mainly in the

common bile

duct and gall bladder, feeding on bile. These animals, which are believed to be the third

most prevalent worm parasite in the world, are endemic to Japan,China, Taiwan,

and Southeast Asia, currently infecting an estimated 30,000,000 humans.

Life Cycle

The egg of a Clonorchis

sinensis (commonly: human

liver fluke), which contains the

miracidium that develops into

the adult form, floats in

freshwater until it is eaten by a

snail.

Once inside of the snail body,

the miracidium hatches from the

egg, and parasitically grows

inside of the snail. The

miracidium develops into a

sporocyst, which in turn house

the asexual reproduction of

redia, the next stage. The redia themselves house the asexual reproduction of free-

swimming cercaria. This system of asexual reproduction allows for an exponential

multiplication of cercaria individuals from one miracidium. This aids the Clonorchis inreproduction, because it enables the miracidium to capitalize on one chance occasion of

passively being eaten by a snail before the egg dies.

Once the redia mature, having grown inside the snail body until this point, they actively

bore out of the snail body into the freshwater environment.
http://en.wikipedia.org/wiki/Fluke_(parasite)http://en.wikipedia.org/wiki/Trematodahttp://en.wikipedia.org/wiki/Platyhelmintheshttp://en.wikipedia.org/wiki/Parasitehttp://en.wikipedia.org/wiki/Liverhttp://en.wikipedia.org/wiki/Bile_ducthttp://en.wikipedia.org/wiki/Bile_ducthttp://en.wikipedia.org/wiki/Gall_bladderhttp://en.wikipedia.org/wiki/Bilehttp://en.wikipedia.org/wiki/Japanhttp://en.wikipedia.org/wiki/Chinahttp://en.wikipedia.org/wiki/Taiwanhttp://en.wikipedia.org/wiki/Southeast_Asiahttp://en.wikipedia.org/wiki/Liver_flukehttp://en.wikipedia.org/wiki/Asexual_reproductionhttp://en.wikipedia.org/wiki/Fluke_(parasite)http://en.wikipedia.org/wiki/Trematodahttp://en.wikipedia.org/wiki/Platyhelmintheshttp://en.wikipedia.org/wiki/Parasitehttp://en.wikipedia.org/wiki/Liverhttp://en.wikipedia.org/wiki/Bile_ducthttp://en.wikipedia.org/wiki/Bile_ducthttp://en.wikipedia.org/wiki/Bile_ducthttp://en.wikipedia.org/wiki/Gall_bladderhttp://en.wikipedia.org/wiki/Bilehttp://en.wikipedia.org/wiki/Japanhttp://en.wikipedia.org/wiki/Chinahttp://en.wikipedia.org/wiki/Taiwanhttp://en.wikipedia.org/wiki/Southeast_Asiahttp://en.wikipedia.org/wiki/Liver_flukehttp://en.wikipedia.org/wiki/Asexual_reproduction


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There, instead of waiting to be consumed by a host (as is the case in their egg stage),

they seek out a fish. Boring their way into the fish's body, they again become parasites

of their new hosts.

Once inside of the fish muscle, the cercaria create a protective metacercarial cyst with

which to encapsulate their bodies. This protective cyst proves useful when the fishmuscle is consumed by a human.

The acid-resistant cyst enables the metacercaria to avoid being digested by the human

gastric acids, and allows the metacercaria to reach the small intestine unharmed.

Reaching the small intestines, the metacercaria navigate toward the human liver, which

becomes its final habitat. Clonorchis feed on human bile created by the liver. In the

human liver, the mature Clonorchis reaches its stage ofsexual reproduction. The

hermaphroditic adults produce eggs every 130 seconds, resulting in the rapid

multiplication of inhabitants in the liver.

Medical Application

Dwelling in the bile ducts, Clonorchis induces an inflammatory reaction,

epithelial hyperplasia and sometimes even cholangiocarcinoma, the incidence of which

is raised in fluke-infested areas.

One adverse effect ofClonorchis is the possibility for the adult metacercaria to consume

all bile created in the liver, which would inhibit the host human from digesting, especially

fats. Another possibility is obstruction of the bile duct by the parasite or its eggs, leading

to biliary obstruction and cholangitis (specifically oriental cholangitis).

Central Serous Retinopathy(CSR) a report of 80 cases by Dr. John Chiao-nan Chang,

M.D. and Dr. Yin-Ping Wang, M.D. Hong Kong on page 125 of their report observed that

19% of the cases of CSR in their sample tested positive forClonorchis sinensis.
http://en.wikipedia.org/wiki/Small_intestinehttp://en.wikipedia.org/wiki/Bilehttp://en.wikipedia.org/wiki/Liverhttp://en.wikipedia.org/wiki/Sexual_reproductionhttp://en.wikipedia.org/wiki/Hyperplasiahttp://en.wikipedia.org/wiki/Cholangiocarcinomahttp://en.wikipedia.org/wiki/Bile_ducthttp://en.wikipedia.org/wiki/Cholangitishttp://en.wikipedia.org/wiki/Small_intestinehttp://en.wikipedia.org/wiki/Bilehttp://en.wikipedia.org/wiki/Liverhttp://en.wikipedia.org/wiki/Sexual_reproductionhttp://en.wikipedia.org/wiki/Hyperplasiahttp://en.wikipedia.org/wiki/Cholangiocarcinomahttp://en.wikipedia.org/wiki/Bile_ducthttp://en.wikipedia.org/wiki/Cholangitis


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PHYLUM ANNELIDA

Hirudo medicinalis

Background

The general morphology of

medicinal leeches follows that of

most other leeches. Fully mature

adults can be up to 20 cm in

length, and are green, brown, or

greenish-brown with a darker

tone on the dorsal side and a

lighterventral side. The dorsal

side also has a thin red stripe.

These organisms have two

suckers, one at each end, called

the anteriorand posteriorsucker

s. The posterior is used mainly

for leverage, whereas the

anterior sucker, consisting of

thejaw and teeth, is where the

feeding takes place. Medicinal leeches have three jaws (tripartite) that look like little

saws, and on them are about 100 sharp teeth used to incise the host. The incisionleaves a mark that is an inverted Y inside of a circle. After piercing the skin and

injecting anticoagulants (hirudin) and anaesthetics, they suck out blood. Large adults

can consume up to ten times their body weight in a single meal, with 5-15 ml being the

average volume taken. These leeches can live for up to a year between feeding.

Medicinal leeches are hermaphrodites that reproduce by sexual mating, laying eggs in

clutches of up to 50 near (but not under) water, and in shaded, humid places.
http://en.wikipedia.org/wiki/Morphology_(biology)http://en.wikipedia.org/wiki/Dorsum_(biology)http://en.wikipedia.org/wiki/Ventralhttp://en.wikipedia.org/wiki/Anteriorhttp://en.wikipedia.org/wiki/Posterior_(anatomy)http://en.wikipedia.org/wiki/Jawhttp://en.wikipedia.org/wiki/Teethhttp://en.wikipedia.org/wiki/Anticoagulanthttp://en.wikipedia.org/wiki/Hirudinhttp://en.wikipedia.org/wiki/Anaesthetichttp://en.wikipedia.org/wiki/Bloodhttp://en.wikipedia.org/wiki/Hermaphroditehttp://en.wikipedia.org/wiki/Sexhttp://en.wikipedia.org/wiki/Morphology_(biology)http://en.wikipedia.org/wiki/Dorsum_(biology)http://en.wikipedia.org/wiki/Ventralhttp://en.wikipedia.org/wiki/Anteriorhttp://en.wikipedia.org/wiki/Posterior_(anatomy)http://en.wikipedia.org/wiki/Jawhttp://en.wikipedia.org/wiki/Teethhttp://en.wikipedia.org/wiki/Anticoagulanthttp://en.wikipedia.org/wiki/Hirudinhttp://en.wikipedia.org/wiki/Anaesthetichttp://en.wikipedia.org/wiki/Bloodhttp://en.wikipedia.org/wiki/Hermaphroditehttp://en.wikipedia.org/wiki/Sex


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Life Cycle

Hirudo medicinalis reproduce once a

year. Their reproduction season lasts

from June to August. All leaches are

hermaphroditic and they get fertilized

on the inside. They get fertilized when

sperm is given to the vagina by an

extendable organ. After this a cocoon is

made around the clitellum and falls off

the anterior section of the leech. The

last step to the Hirudo medicinalis

reproduction cycle is when an egg is

laid in damp soil that is located just

above the shoreline and after 14 days

the eggs are hatched.


Medicinal leeches are now

making a comebackin microsurgery. They provide

an effective means to reduceblood coagulation, to relieve

venous pressure from poolingblood (venous insufficiency),

and in reconstructivesurgeryto stimulate circulation

in reattachment operations for

organs with critical blood flow,

such as eyelids, fingers, and

ears. The therapeutic effect is

not from the blood taken in the

meal, but from the continuedand steady bleeding from the wound left after the leech has detached. The most

common complication from leech treatment is prolonged bleeding, which can easily be

treated, although allergic reactions and bacterial infections may also occur.
http://en.wikipedia.org/wiki/Microsurgeryhttp://en.wikipedia.org/wiki/Coagulationhttp://en.wikipedia.org/wiki/Reconstructive_surgeryhttp://en.wikipedia.org/wiki/Reconstructive_surgeryhttp://en.wikipedia.org/wiki/Microsurgeryhttp://en.wikipedia.org/wiki/Coagulationhttp://en.wikipedia.org/wiki/Reconstructive_surgeryhttp://en.wikipedia.org/wiki/Reconstructive_surgeryhttp://en.wikipedia.org/wiki/Reconstructive_surgery


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Nereis limnicolaBackground

A ragworm is a type of annelid

worm which lives along the

Atlantic shoreline in both North

America and Europe.

The worms can also be found in

parts of the Mediterranean, and

they are extremely abundant,

providing a source of food to

many wading birds and larger

ocean creatures. Some

fishermen are familiar withragworms, as they are

commonly used as bait, and they are available at many fishing supply stores in both

fresh and frozen states.

Life Cycle

Near mating time in most species, the rear part of the body becomes swollen with

sperm or eggs. The worm leaves its shallow burrow on the sea bottom and, usually at

night, releases sex cells near the water surface. After fertilization a spherical larva

(trochophore) emerges from the egg. In some species mating occurs in the burrow. The

female dies soon after.

Some species are simultaneous hermaphrodites (i.e., they have functional reproductive

organs of both sexes) and may even reproduce by self-fertilization. The most common

North American species is Nereis limnicola, found on the Atlantic and Pacific coasts. N.

virens, which may be as long as 80 cm (31.5 inches), occurs on both sides of the North

Atlantic. Some rag worms are commonly used by fishermen for bait

Medical Application

The larger Rag worms (King + Common Rag worm) do bite and it's often enough to

draw blood, they have two pincer like "teeth" at the head and can latch on pretty firmly

to a finger.

The smaller the rag worm the less harmful the bite and some species are harmless but

if you're referring to the live type they sell in fishing stores or that you dig up from your

beach at low tide then yes, this type does bite and many fishermen (or women) have

received nips to the finger while trying to bait their lines. The greenish ones have the

meanest bite.
http://www.britannica.com/EBchecked/topic/409438/http://www.wisegeek.com/what-are-the-different-types-of-worms.htmhttp://www.britannica.com/EBchecked/topic/224938/gametehttp://www.britannica.com/EBchecked/topic/409438/http://www.britannica.com/EBchecked/topic/409438/http://www.wisegeek.com/what-are-the-different-types-of-worms.htmhttp://www.britannica.com/EBchecked/topic/224938/gametehttp://www.britannica.com/EBchecked/topic/409438/


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Lumbricus terrestris

Background

Earthworms (also called nightcrawlers) arevery important animals that aerate the soilwith their burrowing action and enrich thesoil with their waste products (calledcastings). Good soil can have as many asas 1,000,000 (a million) worms per acre.

There are over 3,000 species ofearthworms around the world.These invertebrates (animals without a

backbone) range in color from brown to tored, and most have a soft body.Earthworms range in size from a few incheslong to over 22 feet long. The largestearthworms live in South Africa and

Australia.

Life Cycle

Copulation and reproduction are separate processes in

earthworms. The mating pair overlap front

ends ventrally and each exchanges sperm with the other.The clitellum becomes very reddish to pinkish in color.

The cocoon, or egg case, is secreted by the clitellum

band which is near the front of the worm, but behind the

spermathecae. Some time after copulation, long after the

worms have separated, the clitellum secretes the cocoon

which forms a ring around the worm. The worm then

backs out of the ring, and as it does so, injects its own

eggs and the other worm's sperm into it. As the worm slips out, the ends of the cocoon

seal to form a vaguely lemon-shaped incubator (cocoon) in which the embryonic worms

develop. They emerge as small, but fully formed earthworms, except for a lack of the

sex structures, which develop later in about 60 to 90 days. They attain full size in about

one year, sometimes sooner. Scientists predict that the average lifespan under field

conditions is 48 years, still most garden varieties live only one to two years. Several

common earthworm species are mostly parthenogenetic, that is, with asexual

reproduction resulting in clones.
http://www.enchantedlearning.com/subjects/invertebrates/index.shtmlhttp://en.wikipedia.org/wiki/Copulationhttp://en.wikipedia.org/wiki/Reproductionhttp://en.wikipedia.org/wiki/Ventralhttp://en.wikipedia.org/wiki/Clitellumhttp://en.wikipedia.org/wiki/Cocoon_(silk)http://en.wikipedia.org/wiki/Parthenogenesishttp://www.enchantedlearning.com/subjects/invertebrates/index.shtmlhttp://en.wikipedia.org/wiki/Copulationhttp://en.wikipedia.org/wiki/Reproductionhttp://en.wikipedia.org/wiki/Ventralhttp://en.wikipedia.org/wiki/Clitellumhttp://en.wikipedia.org/wiki/Cocoon_(silk)http://en.wikipedia.org/wiki/Parthenogenesis


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The researchers write that Pheretima (family Megascolecidae, i.e. earthworm) has beendocumented as a potent agent for the treatment of cough and breathing difficultyin traditional Chinese medicine for nearly 2000 years.

In the study, the water extract of Pheretima was separated into three fractions of theethanolic precipitate, the alkaline fraction and the acidic fraction.Guinea pigs tracheal rings were stimulated by histamine to contract, while isolated rattracheal epitheliums was triggered by carbachol to increase short circuit current.Results show that among the three fractions of Pheretima, the acidic fraction shows themost potent spasmolytic effects on histamine-induced contractions and the mostinhibitory activities on carbachol triggered increase in short circuit current.
http://chinesemedicinenews.com/tag/earthworm/http://www.netdoctor.co.uk/medicines/100000455.htmlhttp://www.answers.com/topic/spasmolytichttp://chinesemedicinenews.com/tag/earthworm/http://www.netdoctor.co.uk/medicines/100000455.htmlhttp://www.answers.com/topic/spasmolytic


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PHYLUM MOLLUSCA

Crassostrea virginica

Background

Valve (shell) length of the eastern oyster reaches up to

8 inches (20 cm). Its two shells (called "valves," hence

the name bivalve) attach together at one end by a

natural hinge and by a single large muscle. The pale

white to gray shell is rough with ridges or bumps.

Life Cycle

Approximately 200 adult oysters were obtained from aNew York shellfish grower in April 2003 and held in afloating cage in Rockaway Inlet until they were deployedin Jamaica Bay. The oysters were ~80 mm in shellheight and estimated to be 2 to 3 years old. Shell heightis measured as the distance from the end of the umboto the ventral shell margin (Galtsoff 1964). One hundredoysters were placed in three 1.9-centimeter mesh bags(107 cm 61 cm 8 cm), which were then deployed on

29 April 2003 at BB and 1 May 2003 at FBF. The bags were tied to a cinderblock andwere kept directly on the benthos. Oysters (n = 10 12) from each site were sampled twice per month through August 2003 to determine condition index and reproductivestatus. The mesh bags were replacedwith new bags (identical) on eachsample date to minimize the impact offouling organisms, which reduce flowof water through the cage. Previousexperiences of field work in JamaicaBay suggested the possibility ofvandalism of our deployed cages(Zarnoch and Schreibman 2008). Infact, within the first two weeks ofdeployment, the oyster bags, oysters,and cinderblock at BB went missing,thus substantiating the risks ofworking in an urban system. Resultson adult reproduction are thereforereported for FBF only. Because of thehealth risks associated withconsuming shellfish from Jamaica
http://urbanhabitats.org/v07n01/easternoysters_full.html#cite21http://urbanhabitats.org/v07n01/easternoysters_full.html#cite60http://urbanhabitats.org/v07n01/easternoysters_full.html#cite21http://urbanhabitats.org/v07n01/easternoysters_full.html#cite60


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Bay, the small sample size used in our study was considered a tradeoff for reducedpublic health risks.


Disease-causing parasites may reach epidemic proportions, killing large number ofoysters within a short time. Such epidemic losses have been recorded wherever oystersare found. In Texas, and throughout the Gulf Coast, a parasitic fungus regularly causesmoderate to severe losses among market oysters. A related parasite was responsiblefor the nearly total kill of oysters in Aransas Bay in the 1960's.

Living conditions in the estuary or bay undergo continual and often harsh changes, butthe oyster is highly adaptable. It tolerates siltation, wide temperature ranges, near-freshto very salty water, extreme tidal fluctuations and many other environmental changes.By tightly closing its shell, it can avoid contact with the harmful environment for some

time. However, when its muscle tires, the shell must open and, if conditions have notimproved, the oyster will die.

The oyster must also contend with many predators and parasites. Several types ofcrabs can crack the shell and feed upon the oyster. The oyster drill, a predatory snail,can rasp a hole through the shell and insert a tubular proboscis to reach the flesh.Certain sponges and mollusks burrow into the oyster valves for their own protection butmay riddle the valves with extensive burrows. This weakens the shell and makes theoyster more vulnerable to predation. Organisms such as mussels and other encrustingcolonial animals may crowd the oysters, interfere with feeding, smother young oystersand hinder spat from setting.


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Crassostrea gigas

Background

The shell of Crassostrea

gigas varies widely with the

environment where it is attached.

There are large rounded radial

folds that are often extremely

rough and sharp. The two valves

of the shell are slightly different in

size and shape, the right valve

being moderately concave. Shell

colour is variable, usually pale

white or off-white. Maturespecimens can vary from 80 mm to 400 mm long.

Life Cycle

The larvae of the Pacific oyster are planktotrophic, and are about 70 m at the

prodissoconch 1 stage. The larvae move through the water column via the use of a

larval foot to find suitable settlement locations. They can spend several weeks at this

phase, which is dependent on water temperature, salinity and food supply. Over these

weeks, larvae can disperse great distances by water currents before they

metamorphose and settle as small spat. Similar to other oysterspecies, once the Pacific

oysterlarvae find a suitable habitat, they attach to it permanently using cement secreted

from a gland in their foot.After settlement, the larvae metamorphose into juvenile spat.

The growth rate is very rapid in optimum environmental conditions, and market size can

be achieved in 18 to 30 months. Unharvested Pacific oysters can live up to 30 years.


Japanese oysters appear to be resistant to the two oyster diseases that havedevastated native oyster populations in the Chesapeake Bay a finding that mayboost efforts to find a disease-resistant gene that could aid the native species.

The finding came from a controversial experiment that began June 29 when trayscontaining 200 Japanese oysters and 400 Bay oysters were placed in the York River.

Since then, researchers from the Virginia Institute of Marine Sciences found that 95percent of the native eastern oyster, Crassostrea virginica, died from the diseases MSXand Dermo. None of the Japanese oysters, Crassostrea gigas, died as the result ofdisease.
http://en.wiktionary.org/wiki/concavehttp://en.wikipedia.org/wiki/Larvaehttp://en.wikipedia.org/wiki/Marine_larval_ecologyhttp://en.wikipedia.org/wiki/Apex_(mollusc)http://en.wikipedia.org/wiki/Larvaehttp://en.wikipedia.org/wiki/Larvaehttp://en.wikipedia.org/wiki/Metamorphosishttp://en.wikipedia.org/wiki/Oysterhttp://en.wikipedia.org/wiki/Specieshttp://en.wikipedia.org/wiki/Larvaehttp://en.wikipedia.org/wiki/Habitathttp://en.wiktionary.org/wiki/concavehttp://en.wikipedia.org/wiki/Larvaehttp://en.wikipedia.org/wiki/Marine_larval_ecologyhttp://en.wikipedia.org/wiki/Apex_(mollusc)http://en.wikipedia.org/wiki/Larvaehttp://en.wikipedia.org/wiki/Larvaehttp://en.wikipedia.org/wiki/Metamorphosishttp://en.wikipedia.org/wiki/Oysterhttp://en.wikipedia.org/wiki/Specieshttp://en.wikipedia.org/wiki/Larvaehttp://en.wikipedia.org/wiki/Habitat


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Mytilus edulis

Background

The blue mussel, Mytilus edulis, is a medium-sized

edible marinebivalvemollusc in the familyMytilidae.

In spite of its specific name edulis, it is not the sole

edible Mytilus species.

The shape of the shell is triangular and elongate

with rounded edges. The shell is smooth with

asculpturing of fine concentric growth lines but no

radiating ribs. The shells of this species are purple,

blue or sometimes brown in color, occasionally with

radial stripes as shown here. ) The outer surface of the shell is covered by

the periostracum which as eroded, exposes the colored prismatic calcitic layer is

exposed and also possibly eroded. Blue Mussels are semi-sessile, have the ability to

detach and reattach to a surface allowing the mollusk to reposition itself relative to the

water position.

Life Cycle

Larval development can last from 15 to 35

days depending environmental conditions

including salinity and temperature, as well as

location. Larvea originating from Connecticutmature normally at 1520 C, though at 15 C

normal development occurs at salinities

between 15 and 35 ppt and 20 at 35 ppt at

20 C[8]. The first stage of development is the

ciliated embryo, which in 24-hours for

fertilization form the trochophore. At this point

although mobile, it is still reliant on the yolk for

nutrients. Characterized by a functional mouth

and alimentary canal the veliger stage also has cilia which are used for filtering food as

well as propulsion. A thin translucent shell is secreted by the shell gland forming the

notable straight hinge of the prodissoconch I shell. The veliger continues to mature

forming the prodissoconch II shell. In the end stage of veliger development

photosensitive eye spots and elongated foot with a byssal gland are formed. Once the

pediveliger is fully developed, its foot extends and makes contact with substrate. The

initial contact with the substrate is loose, if the suitable the larva will metamorphoses

into the juvenile form, plantigrade, and attach byssus threads. The mussel will remain in
http://en.wikipedia.org/wiki/Marine_(ocean)http://en.wikipedia.org/wiki/Bivalvehttp://en.wikipedia.org/wiki/Molluschttp://en.wikipedia.org/wiki/Family_(biology)http://en.wikipedia.org/wiki/Mytilidaehttp://en.wikipedia.org/wiki/Mytilus_(genus)http://en.wikipedia.org/wiki/Sculpture_(mollusc)http://en.wikipedia.org/wiki/Periostracumhttp://en.wikipedia.org/wiki/Blue_mussel#cite_note-7http://en.wikipedia.org/wiki/Trochophorehttp://en.wikipedia.org/wiki/Marine_(ocean)http://en.wikipedia.org/wiki/Bivalvehttp://en.wikipedia.org/wiki/Molluschttp://en.wikipedia.org/wiki/Family_(biology)http://en.wikipedia.org/wiki/Mytilidaehttp://en.wikipedia.org/wiki/Mytilus_(genus)http://en.wikipedia.org/wiki/Sculpture_(mollusc)http://en.wikipedia.org/wiki/Periostracumhttp://en.wikipedia.org/wiki/Blue_mussel#cite_note-7http://en.wikipedia.org/wiki/Trochophore


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the state until reaching 1-1.5mm in length. This attachment is the prerequisite for the

foundation for the blue mussel population. In sheltered environments large masses

sometimes form beds which offer shelter and food for other invertebrates.


Blue mussels are filter feeders and play a vital role inestuaries by removing bacteria and toxins.

Mytilus edulis is commonly harvested for food

throughout the world, from both wild and farmed

sources. Mussels are a staple of many seafood dishes in

various cuisines

including Spanish(especially Galician), Portuguese, Fren

ch, Dutch, Belgian and Italian. They are also commonly

used as lab animals.
http://en.wikipedia.org/wiki/Filter_feedershttp://en.wikipedia.org/wiki/Spanish_cuisinehttp://en.wikipedia.org/wiki/Galician_peoplehttp://en.wikipedia.org/wiki/Portuguese_cuisinehttp://en.wikipedia.org/wiki/French_cuisinehttp://en.wikipedia.org/wiki/French_cuisinehttp://en.wikipedia.org/wiki/Dutch_cuisinehttp://en.wikipedia.org/wiki/Belgian_cuisinehttp://en.wikipedia.org/wiki/Italian_cuisinehttp://en.wikipedia.org/wiki/Lab_animalshttp://en.wikipedia.org/wiki/Filter_feedershttp://en.wikipedia.org/wiki/Spanish_cuisinehttp://en.wikipedia.org/wiki/Galician_peoplehttp://en.wikipedia.org/wiki/Portuguese_cuisinehttp://en.wikipedia.org/wiki/French_cuisinehttp://en.wikipedia.org/wiki/French_cuisinehttp://en.wikipedia.org/wiki/Dutch_cuisinehttp://en.wikipedia.org/wiki/Belgian_cuisinehttp://en.wikipedia.org/wiki/Italian_cuisinehttp://en.wikipedia.org/wiki/Lab_animals

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