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Kingdom: Animalia
Subkingdom: Eumetazoa
Superphylum: Platyzoa
Phylum: Platyhelminthes
characteristics :
simple~ soft-bodied
bilaterially symmetrical
invertebrate animal
have no body cavity
have a beginnings of a head region
no specialized circulatory &respiratory organs which restricts them to flattened
shaped~ allow oxygen & nutrients pass their body through diffusion
acoelomates~ characterized by having 3 germs layer
structure of flatworm
habitat
marine, freshwater, damp terrestial environments
locomotion
undulating~ tiny bristles (cilia), help it move as 2 layers of muscles unnder its skin
reproduction
both male and female reproductive body parts.
able to produces sperm and eggs.
Hermaphrodites, able to fertilize themselves (asexual reproduction)
able to reproduce sexually with other worms, most common asexual
able to produce millions of eggs in a day.
eggs are found in the rear section of the tape worm. When the eggs are ready to leave the body they break off and are excreted with digested food. The eggs will remain in the feces until another animal swallows it. The eggs cannot survive very long outside a host's body, so if they are not swallowed by another animal they will die.
Digestion
A flatworm has a combination digestive/excretory system. It takes food in and gets rid of wastes through the same opening
Kingdom: Animalia
Superphylum: Lophotrochozoa
Phylum: Annelida
The annelids ( also called Ringed Worm ), collectively called Annelida (from French annelés "ringed ones", ultimately from Latin anellus "little ring"), are a large phylum of segmented worms, with over 17,000 modern species including ragworms, earthworms and leeches.
Characteristics
consists of multiple segments
each of which has the same sets of organs
Septa separate the segments of many species, but are poorly-defined or absent in some
annelids are soft-bodied
Their bodies are long,
Annelids' cuticles are made of collagen fibers
Body bilaterally symmetrical, metameric, often with a distinct head
Triploblastic body
Asexual reproduction by fission and fragmentation capable of complete regeneration,asexual reproduction by budding in some.
Respiratory gas exchange through skin,gills or parapodia
Locomotion
Many annelids move by peristalsis (waves of contraction and expansion that sweep along the body), or flex the body while using parapodia to crawl or swim.
In some annelids, including earthworms, all respiration is via the skin
many polychaetes and some clitellates (the group to which earthworms belong) have gills associated with most segments, as extensions of the parapodia in polychaetes.
gills of tube-dwellers and burrowers usually cluster around whichever end has the stronger water flow.
Polychaetes can reproduce asexually
dividing into two or more pieces or by budding off a new individual while the parent remains a complete organism. Some oligochaetes, such as Aulophorus furcatus, seem to reproduce entirely asexually
others reproduce asexually in summer and sexually in autumn
asexual reproduction in oligochaetes is always by dividing into two or more pieces, rather than by budding
however, leeches have never been seen reproducing asexually
Kingdom: Animalia
Phylum: Mollusca
Class: Gastropoda
The scientific name for the garden snail is Helix aspersa. It is a gastropod which in latin means, gastro for stomach and pod for foot or just "a belly footed animal".
Characteristics
most mollusks are marine
dorsal body wall forms pairs of folds called mantle whichencloses the mantle cavity, is modified into gills or lung, and secrete the shell (shell absent in some) ventral body wall specialized as a muscular foot variously modified but used chiefly for locomotion
body bilaterally symmetrical (bilateral asymmetry in some), unsegmented, often with definite head.
triploblastic body
Coelom limited mainly to area around heart and perhaps lumen around gonads part of kidney and occasionally part of the intestine
gas exchange by gills, lungs, mantle or body surface
their soft bodies are protected by a hard shell.
its body is long, moist and slimy.
when it is disturbed, it simply withdraws or pulls itself back into its shell.
retreats into its shell and seals the entrance in dry weather to protect its body from drying up.
Habitat
Outer surface of flat pinacocytes, most interior surfaces lined with flagellated collar cells (choanocytes) that create water currents , a gelatinous protein matrix called mesohyl contains amebocytes of various type and skeletal elements
Skeletal structure of fibrillar collagen (protein) and calcareous or siliceous crystalline spicules, often combined with variously modified collagen(sponging)
No Organs or tissues, digestion intracellular, excretion and respiration by diffusion
Reaction to stimuli apparently local and independent in cellular sponges,but electrical signals occur in syncytial glass sponges,nervous system probably absent
Adult sponges are sessile, meaning that they are not able to move from place to place. This characteristic makes sponges seem superficially plant-like but sponges do not share other features of plants.
Sponges are not capable of photosynthesis.
Sponges are diploblasts meaning that they develop from two basic germ layers or cell layers: an ectoderm, or outer layer, and an endoderm, or inner layer
Movement
Although adult sponges are fundamentally sessile animals, some marine and freshwater species can move across the bottom at speeds of 1–4 millimetres (0.039–0.16 in) per day, as a result of amoeba-like movements of pinacocytes and other cells. A few species can contract their whole bodies, and many can close their oscula and ostia.
filter food particles out of the water flowing through them
Particles larger than 50 micrometers cannot enter the ostia
pinacocytes consume them by phagocytosis (engulfing and internal digestion)
Particles from 0.5 to 50 micrometres (2.0×10−5 to 0.00197 in) are trapped in the ostia, which taper from the outer to inner ends
Collar bodies digest food and distribute it wrapped in vesicles that are transported by dynein "motor" molecules along bundles of microtubules that run throughout the syncytium.
Respiration
Sponges' cells absorb oxygen by diffusion from the water flow system, into which carbon dioxide and other soluble waste products such as ammonia also diffuse
Archeocytes remove mineral particles that threaten to block the ostia, transport them through the mesohyl and generally dump them into the outgoing water current, although some species incorporate them into their skeletons.
worldwide - from the polar regions to the tropics
Most live in quiet, clear waters, (sediment stirred up by waves or currents would block their pores, making it difficult for them to feed and breathe)
greatest numbers of sponges are usually found on firm surfaces such as rocks, but some sponges can attach themselves to soft sediment by means of a root-like base.
Most sponges are hermaphrodites (function as both sexes simultaneously)
although don't have gonads (reproductive organs) but sperm are produced by choanocytes or entire choanocyte chambers that sink into the mesohyl and form spermatic cysts while eggs are formed by transformation of archeocytes, or of choanocytes in some species.
JELLY FISH
Characteristics of phylum cnidaria
Cnidocytes present, typically housing stinging organelles called nematocyst
Entirely aquatic, some in fresh water, but most marine
Radial symmetry or biradial symmetry around a longitudinal axis with oral and aboral ends no definite head
Two type of individuals, polyps and medusa
Adult body two layered (diploblastic) with epidermis and gastrodermis derived from embryonic ectoderm and endoderm respectively.
Mesoglea. An extracellular matrix (jelly) lies between body layers, amount of mesoglea varies,some have mesoglea with cells and connective tissue from ectoderm
Incomplete gut called gastrovascular cavity often branched or divide with septa
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 attached to tiny bits of free-living plankton or rarely, fish or other invertebrates
polyps generally have a mouth surrounded by upward-facing tentacles like miniatures of the closely-related anthozoan polyps (sea anemones and corals), also of the phylum Cnidaria.
polyps may be solitary or colonial, and some bud asexually by various means, making more polyps.
Cnidarians feed in several ways:
most obtain the majority of their food from predation but some, including the corals Hetroxenia and Leptogorgia, depend almost completely on their endosymbionts and on absorbing dissolved nutrients.
no respiratory organs
when the water in the digestive cavity becomes stale it must be replaced, and nutrients that have not been absorbed will be expelled with it
some Anthozoa have ciliated grooves on their tentacles, allowing them to pump water out of and into the digestive cavity without opening the mouth.
