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