321 Lab 1 Midterm

Class Hydrozoa

- More colonial -Smalley bell shape, with velum (used for direction during jetpropulsion via controling size of bell

Class Staurozoa

- No alteration of generations -Lack Meduzoa stage Locomotion: Attachemnt and detachment of Basal plate and anchors allows looping type movement

Locomotion of Scyphomedusae vs. Hydromedusae

- Scyphomedusae- uses muscle fibres for periodic contraction to move ( Hydromedusae- uses its velum to propel itself

Morphological Traits of Cnidarian Polyp Hydra

--Cnidocytes present only on the epidermis -Mouth located at apex of Hypostome, tentacel arising from it -Body colum Below Hypostome is called the gastric region - Budding zone, where new polyps arise as asexual buds -

Phylum Cnidaria

-2 layers of epithelia = epidermis and gastrodermis , mesoglea in the middle

Class Hexacorallia

-6 comple septa -No pinnate solitary or colonial -Anemones and stony corals

Class Octocorallia

-8 complete septa and tentacles -Colonial with polyps connected by mesoglea and gastrodermal tubes -Tentacles are Pinnate(with side branches) -sea pens, sea fans , sea whips

Explain dorso-ventral flattening in Hirudinea

-Allow leeches to live along bottom of water -diffusion and uptake of nutrients -High surface volume ratio

Class trematoda Opisthorchis sinensis

-Chinese Fluke -Asexual reproduction via polyembryony

Life cycle of scyphozoa

-Eggs -sperm/Fertilization - Planula - Scyphistoma - Strobilation - Ephyra -Are Gonochoristic = dioecious

Phylum Annelida

-Eucoelomate -Metamerism

Phylum Annelida division

-Hirudina (leeches) -Oligochaeta (earthworm)

Class Scyphozoa feeding

-Injested food taken to 4 gastric pouches contain tentacle called gastric filaments that excrete digestive enzymes - The nutrients absorbed travel through gastrovascular canals -Adradial canals unbranched and INterradial and perradial canals Rhopalium = sensory receptors

Sedentaria-Clitellata-Hirudinea

-Leeches -Ectoparasite -Metanephridea

Subphylum Anthozoa

-No medusa Stage -Distinguished from scyphozoan and hydrozoan via body wall of anthozoans turns into gullet or actinopharynx Similarities with Meduzoa= Mesoglea contains ameboid cells and gastrovascular cavity is subdivided via nematocyst.

Family Terebellidae

-Spaghetti worm

Subphylum Anthozoa sea anemone

-Tentacles -Siphonoglyphs -Gullet -Body Column -Acontia -Coelenteron -septa -Gonad -Pedal Disc -Mouth

Class Turbellaria reproduction

-Transverse Fission/Hermaphroditic 1.penis protruded from "genitial pore" into "copulatory bursa" where sperm is deposited 2.Sperm then Travels to the ovaries , fertilizing the eggs 3. then the fertilized eggs passed down to the yolk cells and discharged from yolk glands

Class Demospongiae

-all have leuconoid body structure -Skeleton, composed of spongin and silicious spicules

Locomotion in sedentaria Lumbricus

-earthworm -shows positive geotaxis -Moves via lengthening circular muscles

Nereis

-prostonium -eyes -palps -peristominum

Anthozoan Life cycle

1.Planula 2. Metamorphosis 3. Young Polyp formed 4. Adult Polyp -Gonochoristic -aexual via vudding

Spicules of demospongiae

Acid did not dissolve

Subphylum Medusozoa similarity

All medusozoans have mitochondrial chromosome that is linear

Whats the benefit of parthenogenesis

All rotifers are homozygous so avoid negative gene mutation

Whats the functional importance of Hemoglobin that binds to oxygen in both terebellidae and Oligochaetaes ?

Allows aerobic respiration , providing ATP

Turbellaria (Dugesia)

Anterior -intestinal caeca -eye spots -auricles -Pharynx -Pharyngeal cavity

Class Hexactinellida (glass sponges)

Aphrocallistes -6 pointed spicules

How are gemmules produced ?

Asexual reproduction via budding

Demospongiae Halichondria

Bread Crumb Sponge -chemical defense = Smell

Spicules of Grantia

Calcarea Grantia -Acid test= dissolved -

What might be the functional value of cnidocytes within the gastrodermis?

Can help with digestion or kill prey if its not already dead

Cestodes Vs. Trematode reproduction

Cestodes: contain Proglottids which undergo polyembryony trematodes: contain sporocyst stage(polyembryony) then redia stage

Phylum Platyhelminthes

Class Turbellaria Class Trematoda Class Cestoda -acoelomate -Protonephridia(osmoregulation/excretion) -Contai Parenchymal cells

Why do Cnidarians have no specialized organs for gas exchange or excretion?

Contain epidermis cells for gas exchange and sxcretion, the larger size allows for more exchange of nutrients and oxygen.

Class turbellaria

Contains Cells in epithelium called Rhabdites: -unique and secrete muscus when in contact with water, used has a defensive function that facilatated diffusion - Contain Neoblast for regenration of body parts -Dugesia, Leptoplana

Taenia sodium life cycle

Cysticercus = bladder worm in intermediate host

How do rotifers survive in extreme environments?

Embryos are encysted in 3 layered shell that protects them from external stressors -can remain dormant for several decades resisting adverse environments

Errantia vs. Sedentaria

Erranatia, co tain well developed parapodia , supported via chitinous rods such as aciculae - appendages and cephalization for sensory functions - eyes, chemosensory structures sedentaria: -head appendages fuction for food capture not sensory -contain eversible pharynx that is not armed with jaws

polychaete division

Errantia(Polychaete with active lifestyle) Sedentaria( Polychaete with sedentary lifestyle in tubes and burrows

What features demonstrate bilateral symmetry and cephalization?

Eye spots

Hydromedusae obelia

Gastrozooid gonozooid coenosarc perisarc stolons

Whats the difference between the body bxominerals between hexacorallia and octocorallia?

Hexacorallia =secrete limestone skeleton which is harder than octocarralia Octocorallia= excrete calcium carbonate skelton in basal epidermis , for more softer shell

Why do siboglinidae have binding sites for for sulfide?

High levels of methane and sulfide in surrounding area , diffuses into siboglinidae , used to generate ATP

Syconoid Sponge

Larger vase shaped, chanocyte-line chambers , open into spongocoel

Anthozoan Metridium

Nematocyst tubules discharged from Cnidocyst of Aconitum

Ecdysozoa

Nematoda and Arthropoda - Moult a cuticle

Locomotion of Turbellaria Dugesia

Planarians move by beating cilia on the ventral dermis, allowing them to glide along on a film of mucus.

Asconoid Sponge

Smallest, vase-shaped, choanocytes line central spongocoel(atrium)

Class Calcarea (Phylum Porifera)

Spicules calcium carbonate

Class Scyphozoa

Swimming via rhythmic contraction of epitheliomuscle cells -Oral arms extend from manubrium(tube of muscular body wall that hangs downwards from undersurface of the bell

Adult Rotifera

Toes contain cement glands , allows attachment to objects in water

siboglinidae anatomy

Trophosome located in the middle region Opisthosoma, help anchor worm to tube

Feeding in turbellaria Dugesia

Use digestive enzymes, neurotoxins, and adhesive secretion swallow prey whole

Phylum Rotifera (rotifers)

Very small body size • Head, trunk, and foot (with toes) • Corona-crownofcilia (swimming and feeding) • Syncytial epidermis with thick layer of cytoskeletal filaments • Mastax(pharynx) with trophi(jaws) • Mouth and anus

Locomotion of ErrantidNereis

Wave like motions , using parapodia and longitudial/ circular muscles

Lophotrochozoa

annelids with mollusk and other phyla

Rotifers locomotion

beat there cilia near mouth to move

Turbellaria cross section

body wall musculature -intestinal caeca -parenchyma -epidermis

Terebellidae(Spaghetti) parapodia function

contain chateau , gills and branchial for selective deposit feeding

Family Sabellidae

example of polychaete feather duster worms - feathers (tubes) are feading organs that make mucus

Family Siboglinidae

hot vent worm

leuconoid sponges

more complex design, no real atrium, several small flagellated chambers instead in which choanocytes are, most adaptive and large type of sponge,

Whty are scyphomedusae higher in particular geographic locations , such as Pacific coast of BC?

more nutrients in water , produces more phytoplankton which produce zooplankton that are a vital source of nutrient for scyphozoa

What is a syncytium?

multinucleate mass of cytoplasm within the cell

Sabellidae(Duster) parapodia function

reduced parapodia used to move up and down tube

What are gemmules?

resistant structures which function in asexual reproduction, capable of surviving adverse environmental conditions

Whats there functional importance?

resistant to hydration, freezing, and low oxygen allowing survial in tough environments

Why should cestodes proglottids not be considered as asexual reproduction?

undergo sexual reproduction

Why do oligochaete have pharyngeal dilator muscles?

use them for sucking, esophagus, and food grinding.

Class Cestoda (tapeworms)

• Endoparasites - adults live in vertebrate intestine • No mouth or digestive cavity • Non-ciliated, syncytial epidermis - specialized for import of nutrients from intestinal lumen of definitive host • Scolex, neck, strobila (chain of proglottids) • Can self-fertilize or cross-fertilize