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03 A legfontosabb állattörzsek: Ősszájúak

2014.04.09

 

PROTOSTOMES - ŐSSZÁJÚAK
Phylum: Sponges
Differentiated cells: different cell types, but no tissues
2 cell layers: inner (entoderm) and outer (ectoderm)
Cell types
Entoderm:
          Choanocyte (galléros-ostoros sejt)
Ectoderm:
          Sclerocytes: make spicules (needles) of skeleton (calcium carbonate, silica, protein)
          Amoeboid cells: move as an amoeba, transport
Reproduction:
          Sexual: hermaphrodites
          Asexual: budding, gemmules („endospore”)
Importance: water purification
Phylum: CNIDARIANS
Tissues
2 cell layers: entoderm, ectoderm
Mesogloea: jelly-like substance between them
Water content: 95-99%
Radial or sometimes bilateral symmetry
2 main body forms:
          Swimming medusa
          Sessile polyp
Parts:
          Mouth
          Gastrovascular cavity
          Epidermis (ectoderm)
          Gastrodermis (entoderm)
          Tentacle
          Mesogloea
Nematocysts: stinging cells
          On the tentacles, trap the prey
Digestion is started in the gastrovascular cavity and finished in the cells (partly extracellular digestion)
Nervous system: decentralized nerve nets (no brain)
Reproduction
Sexual:
          complex life cycle with both polyp and medusa stages
Asexual:
          Budding
          Moving
Epitheliomuscular cells: muscle fibres in them
Medusa: can swim (jet propulsion)
Polyp: rolls
Main species
          Hydra
          Portuguese Man of War
          Moon jellyfish
          Coral
Worms
          Bilateral symmetry
          Integument: simple squamous epithelial tissue with cuticule
          Moving: muscles connected to the integument (bőrizomtömlő)
          Gut: three sections (flatworm: two)
          Breathing: diffusion
          Excretion: protonephridium/elővesécske (flame cell, flatworms) or metanephridium/vesécske (ciliated funnel)
          Nervous system: ganglia
          Reproduction: sexual (with gametes), asexual (splitting)
Phylum: Roundworms
Saprotrophs: in the soil
Parasites:
          Trichinella
          Elephantiasis
          Pinworm (USA), threadworm (UK) – hegyesfarkú bélgiliszta
Phylum: Flatworms
Gut: 2 segments, the second part is branched (transports the nutrients to the cells)
          Planaria – örvényféreg (in water, cilia on the ventral side)
          Common liver fluke – májmétely
          Tapeworm
Phylum: Segmented worms
          Segments
          Complicated gut
          Moving: peristalsis
          Metanephridium
          Closed circulatory system
          Nervous system: ganglia
Species:
          Earthworm
          Leech
Phylum: Molluscs
          Exoskeleton: shell, contains lime
          Main body parts: head, leg, visceral mass (zsigerzacskó)
          Mantle: produces the shell
          Wall of the mantle cavity: breathing organ („gill” or „lung”)
          Nervous system: ganglia (centre: brain ganglion)
          Open circulatory system
Class: Snails
          Shell is twisted (or reduced)
          Head: tentacles, eyes, radula (grasping tongue)
          Foot: slime and cilia
          Visceral mass (zsigerzacskó) contains the most of organs
          Reproduction: hermaphrodites
Class: Bivalves
          Shell: two parts
          Head is reduced
          Feeding: filter feeders (water-cleaning!)
Class: Cephalopods
          Shell is reduced
          Leg is modified to tentacles with suckers
          Moving: swimming with tentacles and jet propulsion
          Eye: similar to the human eye (the most developed in the Protostomes)
          Reproduction: separated sexes
          Types: octopuses, squids
Phylum: Arthropods
          Segmented body and legs
          Strong exoskeleton (chitin)
          It can not stretch, it must be shed (molting)
          Muscles are attached to the inner surface
          Breathing: tracheae (air tubes)
          Open circulatory system
          Nervous system: 2 ventral nerve cords, ganglia (brain, compound eyes)
Class: Arachnids
          Body parts: cephalotorax, abdomen
          On the cephalotorax: pedipalp (tapogatóláb), chelicera (csáprágó)
          Four pairs of legs
          Digestive juices are injected into the prey (external digestion)
          Carnivores or parasites
          Poison glands
          Reproduction: eggs, incomplete metamorphosis
Subclasses:
Scorpions:
          Pedipalp: pincers
          On the abdomen: metasoma (tail) and sting
Acari: mites and ticks
Spiders
Class: Crustaceans
          Cephalothorax, abdomen
          Exoskeleton: chitin + lime
          Compound eyes, 2 pairs of antennae
          5 pairs of walking legs (1st pair are pincers)
          Breathing: gills
          Reproduction: eggs, incomplete metamorphosis
Class: Insects
          Head: antennae, simple and compound eyes, mouthparts: (chewing type - grasshopper, lapping type - bee, siphoning type – butterfly, sucking type - female mosquito)
          Thorax: 3 pairs of segmented legs and 2 pairs of wings (1st can be soft or hard)
          Abdomen:visceral organs, sting
          Respiration: tracheae
          Reproduction: complete and incomplete metamorphosis
          Excretion: Malpighian tubules
Main types: dragonflies, cockroaches, bugs, locusts, grasshoppers, crickets, aphids, beetles, flies, mosquitos, wasps, bees, ants, butterflies