Biodiversity¶

The term protozoa has been abandoned by scientists in favour of the term protist meaning any eukaryotic organism that is not an animal, plant, or fungus.

Protists do not form a natural group, but are a paraphyletic assemblage of similar-appearing. but diverse taxa, said to be members of the Kingdom Protista.

9.7.0 Kingdom Protista (protists)

The old classification of Phylum protozoa:

Protozoa are single-celled (unicellular), but may be colonial if no division of functions.

Gas exchange and excretion is by diffusion.

Osmoregulation in freshwater forms is by a contractile vacuole.

Asexual reproduction is by binary fission and sometimes sexual reproduction by conjugation occurs.

1. Class Rhizopoda, move by pseudopodia, feed by phagocytosis

9.10.0 Phylum Amoebozoa, (Phylum Rhizopoda)

2. Class Mastigophora, move by flagella and feed by direct absorption

9.3.5 Class Euglenoidea, Euglena

3. Class Ciliophora, move by cilia and feed by phagocytosis through a "mouth" part of the cell

9.11.0 Phylum Ciliophora, ciliate, Paramecium

4. Class Sporozoa, parasitic so no obvious method of locomotion, feed by direct absorption from the host

9.7.3 Phylum Apicomplexa, (parasites), Plasmodium vivax

9.1.2 Phylum Porifera¶

Phylum Porifera, (sponges)

Porifera, (Latin porus 'pore', and ferre, 'to bear') Phylum Porifera species are mostly marine in tidal zones attached to submerged rocks. body of two layers, water enters in the body through many pores into the central body cavity, skeleton composed of collagen sponge and calcium carbonate or silica, filter feeders.

9.1.3 Phylum Coelenterata¶

Phylum Coelenterata (Phylum Ctenophora, comb jellies, Phylum Cnidaria, jellyfish, sea anemones)

Classification of Coelenterata

(Nowadays, taxonomists use the following phyla instead of Phylum Coelenterata: Phylum Ctenophora, comb jellies, Phylum Cnidaria, jellyfish, sea anemones)

Phylum Coelenterata, (Greek koilos 'hollow', énteron, 'intestine'), are mostly marine colonial organisms, with two cell layers, ectoderm and endoderm, separated by jelly-like mesogloea, have radial symmetry, hollow cup-like body (enteron cavity), with only one entrance, tentacles around the mouth, independent stinging cells not connected to the network nervous system.

Coelenterata have two body forms:

The hydroid form is a sedentary polyp.

The medusa form is a plankton jellyfish-like organism.

1. Class Hydrozoa, have polyp and medusa forms in the life cycle Order Hydrida

e.g. Hydra, is one of the few freshwater species

Obelia forms a colony of hollow tubes attached to seaweed with polyp heads, hydranths, specialized either for feeding or for reproducing by medusa buds.

Order Siphonophora, marine pelagic with apical float, pneumatophore e.g. Physalia, "Portuguese man-of-war"

See diagram 9.37.6 Physalia, "Portuguese man-of-war".

In Australia, it is commonly called a "bluebottle", where the dactylozoids detach in the water off the surfing beaches and surfers are stung by the nematocysts.

2. Class Scyphozoa, jellyfish, medusa form is the main stage in the life cycle, e.g. Aurelia

The "jellyfish", which may be classified as Phylum Cnidaria, subphylum Medusozoa, refers only to the medusa phase of the life cycle.

Some aquariums use the term "sea jellies"instead of "jellyfish", because it is not a "fish".

3. Class Anthozoa (Actinozoa), only the polyp stage in the life cycle, Order Alcyonaria, corals,

e.g. Red coral, Corallium rubrum, Order Zoantharia

9.1.4 Phylum Platyhelminthes¶

Phylum Platyhelminthes (flatworms)

Classification of Platyhelminthes

Many Platyhelminthes are parasites of humans and other animals.

To control these parasites, their life cycle can be broken by killing the hosts or parasites in the host, thoroughly cooking food that contain parasites, and sanitary disposal of human and animal wastes.

Make sure that children wash their hands thoroughly after handling cats and dogs.

Platyhelminthes have a dorsiventrally-flattened body (flattened from above), bilateral symmetry (head, tail, left and right sides), three cell layers: (ectoderm, mesoderm, endoderm), but no body cavity.

Both sex organs are present in the one organism (hermaphrodite).

They have a primitive brain and paired ventral nerve cords.

The three classes of platyhelminthes are as follows:

1. Class Turbellaria, planarians, are free-living flatworms with simple anterior eyes and can replace lost body parts (regeneration).

They move with cilia and rhythmical muscle contraction to scavenge detritus.

2. Class Trematoda, flukes, have a complex attaching devices of suckers and sometimes hooks.

They attach themselves to the interior of the host and suck in blood and mucus with a muscular pharynx.

Cat liver fluke (Opisthorchiasis felineus)

Chinese liver fluke (Clonorchis sinensis)

Lung fluke (Paragonimus westermani)

Schistosoma fluke (Schistosoma mansoni, S. japonicum), bilharzia, schistosomiasis disease, infection by skin penetration, parasite in freshwater snails

Sheep liver fluke (Fasciola hepatica)

3. Class Cestoda, tapeworms, attach to the gut wall of host by an attaching device (scolex) with hooks and suckers.

The body is divided into segments (proglottids) that are continually produced behind the scolex.

They remain attached to the interior of the hosts digestive system and absorb the pre digested food.

Pork tapeworm (Taenia solium), infection from eating undercooked pork

Hydatid tapeworm (Echinococcus granulosis), infection from faeces in dog fur

See diagram 9.37.3: Life cycle of Echinococcus granulosis.

Cat tapeworm (Dipylidium caninum), infection from ingestion of cat flea.

9.1.5 Phylum Nematoda¶

Ascaris lumbricoides (human intestinal roundworm)

Slide – Echinococcus Granulosus of Entire Worm, MTA, (Commercial).

See diagram 9.37.9: Rhabditis mature female.

9.1.6 Phylum Annelida¶

Phylum Annelida, segmented worms, ringed worms, annelids

See diagram 9.37.8 TS (Lumbricus terrestris).

Annelids, soft cylindrical bodies, segmented, bilaterally symmetrical, blood vessels, bristles (chaetae), gametes, paired ventral nerve cords

The main body cavity (coelom) is surrounded by mesoderm with ducts to exterior to carry wastes, (filtered by nephridia).

Classification

Class Polychaeta

Mostly marine, move by undulations and parapodia bearing many chaetae, separate sexes, free-swimming larva, distinct head, bristle worms, polychaetes (paddle-footed annelids, usually marine swimming worms), Nereis ragworm

Sipuncula (sipunculan worms, peanut worms) (Phylum Sipuncula), Sipunculus, Phascolosoma

Echiura, spoon worms, burrow worms, echiuran worms, (marine), Bonellia green spoonworm

Class Oligochaeta

Earthworms, angleworms, Lumbricus common earthworm, Allolobophora green worm, Eisenia red wriggler worms

terrestrial burrowing, digest garden detritus, move by peristalsis ripples, few chaetae, hermaphrodite, eggs laid in cocoons, no larva

Class Hirudinea

Leeches, suck blood, use anticoagulant, segments divided into rings, no chaetae or parapodia, hermaphrodite, eggs laid in cocoons, no larva.

Hirudo medical leech

Class Pogonophora (beard worms), Riftia giant tube worm

Earthworm behaviour, Lumbricus terrestris)

The British naturalist Charles Darwin (1809–1882) published his book on The Formation of Vegetable Mould, through the Actions of Worms, With Observations on their Habits (1881). Experiment

See diagram 9.3.32: Earthworm observation box.

The burrowing behaviour of the common earthworm, (Lumbricus terrestris), provides valuable aeration of agricultural soils.

Make a wooden observation box 30 cm × 30 cm × 15 cm fitted with a glass front to studying the habits of earthworms.

Fill the box nearly to the top with successive layers of 1. sand, 2. leaf mould, and 3. loam soil.

Push down each layer before adding the next layer.

Put lettuce leaves, dead leaves, and pieces of carrot on the surface of the soil.

Loosen the surface of the soil and gently drop on some earthworms.

Watch them burrow into the loose soil.

Keep the contents of the box damp and study the behaviour of the worms through the glass front of the observation box.

9.1.7 Phylum Arthropoda, spiders, ticks, water flea, shrimps, crabs, barnacles, millipedes, centipedes¶

Subphylum: Chelicerata Class: Arachnida, arachnids, horseshoe crabs, sea scorpions, harvestmen, camel spiders, mites, ticks, whipscorpions, scorpions, vinegaroons, spiders,

over 110,000 species including 51,000 spiders, mostly terrestrial, body divided into cephalothorax and abdomen, eight legs attached to the cephalothorax,

first pair of legs, chelicerae, for feeding and defence, second pair of legs for feeding, locomotion, reproduction, pair of pinchers in scorpions, mites larva 6 legs

Subphylum Myriapoda, (myriapods) segmented body, a pair of antennae, spiracles, millipedes, centipedes)

House Centipede, (Allothereua maculata), (Greek murias 'ten thousand', pod 'foot')

Subphylum Crustacea, crustacean

Class Branchiopoda, brine shrimps, water flea (Daphnia)

Class Cephalocarida, horseshoe shrimps

Class Copepoda, copepods, fish lice

Class Malacostraca, crayfish, prawn, crabs, krill, lobsters, crayfish, crabs, shrimps

Class Maxillopoda, copepod, barnacle

Class Ostrocoda, seed shrimps

9.1.7.1 Class Insecta¶

Orders of insects

Order Anoplura, sucking lice

Order Aptera, wingless, fleas, silverfish

Order Coleoptera, forewings fully hardened), weevils, scarabs, chafers, dung beetles, longicorn beetles, jewel beetles

Order Diptera, two‑winged, flying wings and 'halteres' for balance, mosquitoes, midges, sand flies, blowflies house fly

Order Ephemoptera, smaller membranous hindwings, held upright at rest and often pressed together, mayflies

Order Hemiptera, forewings partly hardened, sucking mouthparts, aphids, hoppers, scale insects, cicadas, water striders, bed bugs

Order Hymenoptera, two pairs of membranous wings, body has distinct waist, ants, wasps, bees, sawflies, vinegar fly

Order Lepidoptera, scaly wings, butterflies, moths

Order Megaloptera, alderflies, dobsonflies

Order Neuroptera, main veins in the wings, net-winged, lacewings, mantid flies, antlions

Order Odonata, at rest spread wings out to the side, dragonflies, damselflies

Order Plecoptera, stoneflies

Order Trichoptera, caddisflies

9.1.7.2 Order Diptera¶

Fruit fly, (Drosophila melanogaster), vinegar fly, deposits eggs on rotting ripe fruit.

The species has its origins in the woodlands of south-central Africa, where it relied heavily on the marula fruit, Sclerocarya birreaica.

The “true” fruit flies, tephritid flies, are larger and more colourful and attack fruit before it rots.

Drosophila flies may be abundant in wineries, stone fruit orchards and banana plantations during harvest.

They are small, easy to feed, have a very quick life cycle and can produce hundreds of offspring.

The Drosophila life cycle lasts approximately 10 days at 25°Cm and a single fertile female can lay hundreds of eggs.

Drosophila embryogenesis lasts approximately 24 hours.

Drosophila melanogaster that genes were found to be bundled up in chromosomes, when its genome was sequenced in the 1990s.

Fruit flies have been crucial in mapping the molecular interactions involved in allowing cells to migrate and stitch together to repair tissue damage.

Drosophila melanogaster has contributed directly to disease control.

Wolbachia bacteria, isolated from this species, are used to suppress the transmission of dengue disease and other human viral diseases transmitted by mosquitoes.

A strain of Wolbachia living inside the tissues of fruit flies and passed from mother to offspring was transferred through microinjection to Aedes mosquitoes.

The Wolbachia bacteria interact with viruses in such a way as to prevent viral build-up in the salivary gland of the mosquitoes.

9.9.2.0 Order Diptera, mosquito

9.9.1.0 Order Diptera¶

(true flies, two-winged flies, bee flies, blow flies, blue bottles, bot flies, crane flies, daddy long legs, fruit flies, gall midges, gnats house flies, hover flies, midges, moth flies, sand flies, tsetse flies, vinegar flies)

Suborder Brachycera (circular-seamed flies, muscoid flies, short-horned flies)

Family Drosophilidae (pomace flies, small fruit flies, vinegar flies)

(Drosophila melanogaster) (common fruit fly)

9.9.2.0 Order Diptera¶

Mosquito

Suborder Nematocera (long-horned flies)

Family Culicidae (mosquitoes)

(Anopheles gambiae) (South American mosquito)

(Culex tarsalis) (North American mosquito)

(Aedes notoscriptus), "backyard mosquito", Australia

(Aedes vigilax), salt marsh mosquito, Australia

9.1.8 Phylum Mollusca¶

Molluscs have an unsegmented, soft body, a muscular foot or tentacles, a mantle that can secrete a shell, a radula (tongue with teeth).

Molluscs can be found in marine, terrestrial and freshwater environments, and most molluscs are snails and slugs.

Natural pearls are formed when a small, foreign object gets stuck inside an oyster.

Class Gastropoda, (gastropods), snails, slugs abalone, limpets, conch shells, nudibranchs.

Class Bivalvia, (bivalves), clams, oysters, scallops, mussels.

Class Polyplacophora, chitons, eight overlapping plates, live attached to rocks in tidal areas, use radula to scrape off algae.

Class Cephalopoda, (cephalopods), squid, octopuses, cuttlefish, nautiluses.

Class Scaphopoda, (scaphopods), tusk shells, curved tooth-like, open-ended shells, live in marine sand and mud.

Class Aplacophora, spicule worms, look like worms with spicules in skin instead of a shell, live in deep-water habitats.

9.1.9 Phylum Echinodermata¶

Echinoderms have basic adult parts in fives, calcite skeleton, hydraulic tube feet or a water-vascular system.

They occur mainly in shallow coastal or reef waters.

Class Asteroidea, (asteroids), starfish or sea stars

Class Crinoidea, (crinoids), feather stars and sea lilies

Class Ophiuroidea, (ophiuroids), brittle stars and basket stars

Class Echinoideasea, (echinoids), sea urchins, heart urchins and sand dollars

Class Holothuroidea, (holothuroids), sea cucumbers, trepang or bêche de mer

Crown-of-Thorns starfish, (Acanthaster planci), huge increase in numbers and destructive effects on the corals of Australian Great Barrier Reef.

9.1.10 Phylum Chordata¶

Phylum Chordata, Chordata, chordates

Chordates have a nerve cord along the back of the body, and a 'notochord' or firm rod of cells beneath the nerve cord.

gill slits, (not in some chordates, but were present during evolutionary development)

Dingo

Dingo, (Canis familiaris) Family Canidae Order Carnivora Class Mammalia Phylum Chordata The dingo is a placental mammal, an ancient breed of domestic dog, introduced to Australia by seafarers, about 4,000 years ago.

Its origins have been traced back to early breeds of domestic dogs in south east Asia.

Te earliest archaeological finding has been dated to 3,250 years ago.

The coat colour is mainly ginger with white feet and body mass is 12-24 kg.

The body fur is short while the tail is bushy.

Its canine teeth are longer than those of a domestic dog, and the dingo's muzzle is also longer and tapered.

Dingoes can live in a wide range of habitats found on the Australian mainland.

However, after European colonisation and the growth of pastoralisation, dingoes were removed from farming and grazing areas.

9.1.12 Subphylum Urochordata¶

Subphylum Urochordata (sea squirts, tunicates)

Ascidians have a primitive backbone at some stage of their life cycle, most are hermaphrodites and reproduce by external fertilisation.

Their free-swimming larva, ascidian tadpoles, secrete slime and attach themselves to a rock surface head-first, and then absorb their tail.

Adult ascidians are unable to move around and filter food particles from the water by pumping water in one siphon and out the other.

Ascidians are called "sea squirts", because they squirt jet of water if trodden on when they are uncovered at low tide.

9.1.13 Subphylum Vertebrata¶

Vertebrates have a vertebral column, bony vertebrae separated by mobile discs, developed from the notochord.

9.1.14 Class Agnatha¶

Class Agnatha, Petromyzontida, jawless fish

Cyclostomi (hagfish and lampreys)

Agnathans are the oldest fossils with a skull but no jaws.

Hagfish have no scales, weak eyes under skin, and live deep in the ocean.

Lampreys, lamprey eels, parasitic on river and lake fish, two eyes and two primitive eyes, fishing pest, but good to eat and cook to make jellied eels.

Superclass Gnathostomata (jawed vertebrates)

9.1.15 Class Chondrichthes¶

Class Chondrichthes, (cartilaginous fish), elasmobranchs, (sharks, dogfish, stingrays)

Chondrichthyes (Greek khóndros 'cartilage' and ikhthús 'fish'), jawed fish, which all have skeletons primarily composed of cartilage.

Chondrichthyes are aquatic vertebrates with paired fins, paired nares, placoid scales, conus arteriosus in the heart, and no opercula and swim bladders.

Subclass Elasmobranchii contain the sharks, rays, skates and sawfish.

Subclass Holocephali contain the chimaeras, ghost sharks

Size of elasmobranks is from 10 cm, finless sleeper ray, to the over 10 m, whale shark.

9.1.16 Class Osteichthyes¶

Class Osteichthyes, (bony fish, "fish")

Osteichthyes or bony fish, which have skeletons primarily composed of bone tissue.

Since 2019, understanding of how species composition of fish assemblages varies with changing habitat and environmental conditions has advanced.

The range of suitable habitat for some important fishery species will substantially reduce, e.g. red throat emperor, dusky flathead and blue threadfin salmon.

Some species may increase their distribution, benefiting from increased prey availability, e.g. the flowery rock cod and barred javelin.

Some species of bony fish are farmed, i.e. grown and harvested in an aquaculture system

9.1.17 Class Sarcopterygii¶

Class Sarcopterygii, (lobe-finned fishes, coelacanths)

Genus: Latimeria, Species chalumnae, Family Latimeriidae, Class Sarcopterygii, Subphylum Vertebrata, Phylum Chordata

Coelacanth, (Latimeria chalumnae), has muscular lobes in the fins, attached to the appendicular skeleton.

Such fins may have paved the way for the limbs of the first land vertebrates to evolve.

Coelacanths reside at ocean depths of as much as 800 m and female coelacanths may reach up to 2 m long and weigh 110 kg.

9.1.18 Subclass Dipnoi¶

Subclass Dipnoi (lungfishes)

Genus Neoceratodus Species forsteri Family Ceratodontidaei Subphylum Vertebrata Phylum Chordata Kingdom Animalia

Australian Lungfish, (Neoceratodus forsteri), can breathe air by coming to the surface when freshwater habitat is stagnant or the quality is low.

The Australian Lungfish has only a single lung, all other species have a pair, and can grow to 1.5 metres in length and 40 kilograms in weight.

It has a long, heavy body with large scales, small eyes, paddle-like pectoral fins and pelvic fins.

It is usually olive-green to brown on the back and sides with some scattered dark blotches, and whitish ventrally.

It occurs naturally in the Burnett and Mary River systems of Queensland, Australia, although it has been introduced into other rivers.

9.1.19 Class Amphibia¶

Class Amphibia, (amphibians), (frogs, toads, newts, salamanders)

The three main groups of amphibians are the frogs, salamanders and caecilians, but only the frogs are present in Australia.

Although some Australian frogs have ‘toad’ in their names, there are no ‘true’ toads (i.e. members of the family Bufonidae), native to Australia.

However, one species of true toad, the Cane toad,(Rhinella marina), has been introduced to the country.

It is now considered to be an invasive species.

Poison secreted by glands in the toad’s skin causes native predators to fall ill after eating the amphibian.

The poison is often fatal.

Four families of frogs in Australia:

1. Hylidae (tree frogs), 2. Microhylidae (narrow-mouthed frogs). 3. Myobatrachidae (southern frogs), 4. Ranidae (true frogs)

9.1.20 Class Reptilia¶

Class Reptilia, reptiles, (snakes, lizards, crocodiles, alligators, turtles, tortoises, tuataras)

Snakes

Turtles

1. Hard-shelled sea turtles

Family Cheloniidae

Loggerhead turtle (Carella caretta), Pacific Ridley turtle (Lepidochelys olivacea), Flat back turtle (Natator depressus)

2. Leathery sea turtle Family Dermochelyidae

Leathery turtle (Dermochelys coriacea)

3. Side-necked freshwater turtles

Long-necked turtles Genus Chelodina, Snapping turtles Genus Elseya

Southern snapping turtle, (Elseya albagula), Mary River turtle (Elusor macrurus), Snake-necked turtle, (Chelodina longicollis) Also, Emdura, Pseudoemdura, Rheodyte

In Australia, a freshwater turtle is popularly known as a "tortoise", but in other countries a tortoise is a domed-shaped terrestrial reptile.

4. Pig-nosed turtle

Family Carettochelydidae, (Carettochelys insculpa)

5. Red-eared slider

Family Emydidae, Red-eared slider, (Trachemys scripta elegans), is the most common pet turtle in the world.br>

Geckos

Asian house gecko (Hemidactylus frenatus), "the chuck chuck", Flap-footed lizards, "legless lizards", Family Pygopodidae

Worm lizards, Aprasia

Skinks, Family Scincidae, Blue tongued lizards, Genus Tiliqua, Eastern Blue tongue lizard (Tiliqua scincoides)

Bicycle lizards, Amphibolurus

The crested dragon bicycle lizard (Ctenophorus cristatus) runs on hind limbs

(Moloc horridus), it has thorn-like spines and eats ants

Family Varanidae, Genus Varanus, Australian lace monitor (Varanus varius) uses termites nests to hatch eggs.

9.1.22 Class Mammalia¶

Mammals: Monotremes, Marsupials, Placentals.

Mammals are warm-blooded animals that have mammary glands, which produce milk, hair of some form, a single bone on each side of the lower jaw, live birth.

Monotremes, platypus, echidna, lay eggs, so not "live birth".

Marsupials, kangaroos, bandicoots, quolls, koala, give birth to poorly developed young, which are then carried in a pouch.

Placental mammals, (eutherian mammals), rodents, bats, cats, dogs, goats, foxes, rabbits produce well-developed offspring.

Marine mammals, seals, sea lions, whales, dolphins, dugong, cannot breathe underwater, but have developed adaptations to aquatic life.

9.1.23 Rabbit¶

Kingdom: Animalia, Animals

Phylum, (Division): Chordata

Subphylum: Vertebrata

Class: Mammalia

Order: Lagomorpha

Family : Leporidae

European rabbit: (Oryctolagus cuniculus)

9.2.0 Archaea¶

Archaea, prokaryotes, have no cell nucleus, no mitosis, no meiosis

Archaea, live in hot acid environment and are mostly anaerobic

Methanococcus jannaschii, lives in hydrothermal vents and its genome has been sequenced.

It derives energy from hydrogenotrophic methanogenesis, an ancient form of respiratory metabolism.

4H₂ + CO₂ → CH₄ + 2H₂O source

9.3.0 Kingdom Chromista¶

Kingdom Chromista have tinsel-type flagella with brush-like extensions.

Class Ulvophyceae, ulvophytes

Class Xanthophyceae, yellow-green algae

9.3.1 Class Bacillariophyceae¶

Class Bacillariophyceae, diatoms

Class Bacillariophyceae, (Bacillariophyta), diatoms, plankton, diatomaceous earth, silica shells (silica cell walls), photosynthesis.

Diatoms are unicellular microscopic algae with a silica wall and occur as plankton and fossil forms, e.g. diatomaceous earth.

The word diatom means "cut in two".

Diatoms occur as single cells, colonies or long colonial chains, are yellow to light brown colour.

Their cell walls consist of overlapping silica cells, each like a petri dish.

They float freely in the water or clinging to seaweed, crustaceans and whales.

Example genera: Actinocyclus, Bacillaria, Bellerochea, Cyclotella, Chaetoceros, Cylindrotheca, Fragilaria, Nitzschia, Phaeodactylum, Skeletonema, Thalassiosira

Didymo or rock snot (Didymosphenia geminata) is invasive and causes a mush in freshwater streams.

(Melosira granulata) is a fossil diatom with radial symmetry.

Navicula are boat-shaped diatoms that can move over surfaces using a layer of protoplasm.

9.3.2 Class Chrysophyceae¶

Class Chrysophyceae, (golden-brown algae) Chrysophyte, an alga of the class Chrysophyceae, has two flagella, a red eyespot, yellow-brown chloroplasts and often silica scales on the outside.

The chrysophyte, (Synura australiensis, is a golden-brown algae containing chloroplasts, found mostly in freshwater, covered in silicate scales and yellow colour.

A group of Synura cells aggregates and assembles into a cluster, with each cell has its two flagella facing outward.

9.3.3 Class Cryptophyceae¶

Class Cryptophyceae, (cryptomonads), (Cryptomonas)

The Cryptophyceae are a group of flagellate protists including both photosynthetic and phagotrophic taxa.

The cryptomonad, (Cryptomonas paramecium) has an elongate body, two equal in length flagella, anterior gullet, nucleus, contractile vacuole, frequently filled with starch grains, rotates while swimming, can also swim backwards, occasionally jumps backwards unlike most cryptomonad it is colourless and without chloroplasts.

9.3.4 Class Dinoflagellata¶

Class Dinoflagellata, dinoflagellates

(Noctiluca scintillans), causes red tide fire in the sea.

(Ceratium polysaccharide), wall has horn-like shapes.

Harmful algal blooms (red tides), are caused by (Karenis brevis) and Alexandrium.

Ciguatera disease is caused by eating reef fish infected by (Gambeirdiscus toxicus).

Ciguatoxins, C₆₀H₈₆O₁₉, Ciguatoxin CTX, is a commonly encountered fish toxin, especially in the Giant moray eel (Gymnothorax javanicus). source

Dinoflagellates occur in enormous numbers in the ocean, particularly in tropical waters and display a huge diversity of form.

9.3.5 Class Euglenoidea¶

Class Euglenoidea, (euglenids), (Euglena gracilis)

Phylum: Eugleophyta, Family: Euglenaceae, Genus: Euglena, Species: Euglena gracilis

Euglena species are freshwater single-cell flagellates, which live in water habitats rich in organic matter, has chlorophyll and may form green or red “blooms” in ponds or lakes.

Euglena has a long flagellum at the anterior of the cell for swimming, chloroplasts surrounded by three membranes, pyrenoid centres of carbon dioxide metabolism.

It has a flexible pellicle instad of a cell wall.

It can both use phtosynthesis and feed on organic matter.

It has a red eyespot (stigma) for phototaxis, no cell wall, a "pellicle"of proteinaceous strips surrounds the cell, no records of sexual reproduction.

It requires an external supply of vitamin B12.

The species (Euglena sanguinea) produces the alkaloid toxin Euglenophycin, C₂₀H₃₅NO, causing fish kills source

The main storage product is paramylon, C₁₈H₃₂O₁₄ and Euglena is produced commercially as a source of paramylon. source

Paramylon is a glucose polymer similar to cellulose, but they differ in how the glucose units are linked.

(Cellulose contains β-1→4 glucan linkages, but paramylon has β-1→3 glucan linkages.

9.3.6 Class Haptophyta¶

Haptophyta are planktonic and phototrophic organisms in the worldwide marine environments and mat form massive blooms, which are toxic.

They have a haptonema, a third appendage used for attachment and food handling, two similar flagella, two golden-brown chloroplasts, organic body scales.

Haptophyte (Tisochrysis lutea) is rich in docosahexaenoic acid, (DHA), C₂₂H₃₂O₂, so is used to prevent obesity and improve lipid and glucose metabolism. source

9.3.7 Class Mycetozoa¶

Class Mycetozoa, (slime moulds)

Common coral slime, (Ceratiomyxa fruticulosa), plasmodial slime mould, widely distributed on decaying wood, white frost-like growth or thin watery layers.

They have pillar or wall-like sporangia buds from the plasmodium.

They develop spores which become flagellated zoospores that will later form new plasmodia.

Ceratiomyxa (Latin ceratus 'waxed', Greek myxa 'mucus'), Eumycetozoa

9.7.1 Phylum Acrasiomycota, slime moulds

9.3.8 Class Oomycetes¶

Class Oomycetes, water moulds, biflagellate zoospores, one anterior and one posterior flagellum

Oomycetes, water moulds, downy mildews, not photosynthetic, rusts, egg "fungi", not a fungus. but similar to brown algae.

[Oomycetes is also classified in KingdomChromista]

(Albugo candida) (Cystopus), water mould, white rust

(Aphanomyces raphani) black root of radish

(Bremia lactucae), downy mildew of lettuce

(Peronospora cubensis), downy mildew of cucurbits, e.g. cucumber

(Phytophthora infestans), late blight of potatoes, potato blight

9.3.10 Class Raphidophyceae¶

Raphidophytes are similar to the Phylum Tribophyta, but with a distinctive internal cell structure.

All are unicellular with no cell walls and no eyespot, marine and mostly freshwater, large single cells with no cell walls, two flagella, many chloroplasts.

The marine species may cause non-toxic algal blooms, e.g. Gonyostomum.

Examples: Chattonella, Chloromorum, Gonyostomum, Heterosigma, Psammamonas, Vacuolaria

9.3.11 Phylum Rhodophyta¶

Phylum Rhodophyta, red algae

Carrageenans, red seaweed, Rhodophyceae

Carrageenans are mainly marine, as single cells or filaments, are used to make agar, dulse, nori, contain phycocyanin and phycoerythrin in chloroplasts.

Ceratium colours the upper ocean red.

(Gigartina atropurpurea) is a giant marine kelp.

Gymnodinium, causes red tide, "algal bloom".

Noctiluca causes bioluminescence.

Pyropia is used for "nori", Japanese food.

9.5.0 Phylum Heterokontophyta¶

Heterokontophytes is a group of algae, also known as ochrophytes or stramenochromes.

As of 2024, ochrophytes amount to 23,314 described species, of which the majority are diatoms.

They are the photosynthetic organisms with a cell nucleus, characterized by the presence of two unequal flagella.

They can be single-celled, colonial, coenocytic or multicellular.

All ochrophytes have folds in the mitochondria to increase thr area for cellular respiration.

They are algae, distinguished from other groups of algae by their flagella, chloroplasts and pigments.

They are mostly photosynthetic, but some groups have lost photosynthetic capacity and pigments.

Ochrophyte chloroplasts contain chlorophylls a and c as photosynthetic pigments, in addition to fucoxanthin.

Ochrophyte algae accumulate Leucasin, C₄₂H₇₀O₁₂ as a storage product, but they lack starch. source

Ochrophytes are present in nearly all environments, including marine habitats, freshwater or soil.

Ochrophytes include brown algae (Phaeophyceae), golden algae (Chrysophyceae), e.g. Hydrurus, and yellow-green algae (Xanthophyceae), e.g. Vaucheria.

Some diatoms, e.g. Cocconeis, grow attached to the substrate through adhesive films, but Eunotia and Nitzschia grow stalks or colonial tubes.

Unicellular algae Heterosigma and Chattonella, Raphidophyceae, cause fish mortality.

Gonyostomum mucilage damages fish gills and causes algal blooms.

The diatom Chaetoceros clogs fish gills.

(Pseudonitzschia australis) produces neurotoxin domoic acid, C₁₅H₂₁NO₆, to cause human shellfish poisoning, mass wildlife mortality and widespread fishery closures. source

9.6.0 Chromista - Phytophthora¶

Kingdom Chromista, Phylum Oomycota, Order Peronosporales, Family Peronosporaceae, Genus Phytophora

Phytophthora are not called fungi, because they have cellulose cell walls, whereas fungi have chitin cell walls.

They have diploid chromosomes in non-reproductive stage (fungi haploid cells).

They have hyphae that lack cross walls, coenocytic hyphae and they have two types of flagella.

Phytophthora, brown rot disease of citrus, affects especially "Washington Navel" orange and lemons, top and root rot of pineapple

Phytophthora cause collar rot of citrus, phytophthora blight of passionfruit, cocoa black pod, cinnamon root rot in hemlock, root rot and stem cankers in citrus trees, red root rot of strawberries, fruit rot in coconut and betel nut, soybean root rot

Phytophthora infestans, causes potato (late) blight, in the Great Famine of Ireland

Phytophthora in Australia, mostly (Phytophthora cinnamomi), cinnamon "fungus", root rot, cause 'dieback' to many plant species and citrus farms.

9.6.2 Subphylum Crustacea¶

Class Malacostraca (crabs, krill, pill bugs, shrimp)

Class Branchiopoda (branchiopods)

Artemia salina (brine shrimp) in inland salt water lakes

Artemia nyos ("Sea-monkey" (toy product)

Order Cladocera (water fleas)

Daphnia pulex

Subclass Cirripedia (barnacles)

Class Ostracoda (ostracods)

9.7.0 Kingdom Protista¶

A protista has such simple cellular organism that it is not classified as a plant, animal or fungus.

Most protista are unicellular, and live in water or water soil or are parasitic.

Some protista are multicellular algae, e.g. kelps - seaweeds without specialized tissues.

All protista have a nucleus, so are eukaryotic.

Protista may be heterotrophic or autotrophic, i.e. chemotrophic or phototrophic.

9.7.1 Phylum Acrasiomycota, slime moulds¶

Phylum Acrasiomycota, slime moulds

Acrasiomycota, (cellular slime moulds), causes powdery scab on potatoes.

Formerly it was thought to be a fungus hence the "mycota", e.g. Guttulinopsis, Pocheina.

9.7.3 Phylum Apicomplexa¶

Babesia causes Babesiosis,

(Plasmodium vivax) causes Malaria,

Cryptosporidium in drinking water causes Cryptosporidiosis,

(Toxoplasma gondii) causes toxoplasmosis.

9.7.7 Phylum Myxomycota¶

Myxomycota, slime moulds, are fungi-like organisms that may move around like an amoeba or a blob called a plasmodium.

They live on decomposing vegetation and they consume bacteria.

They may be seen as creeping and crawling threads of “slime” in their motile stage.

However, as food becomes scarce, these threads come together and form a fruiting body that produces spores.

The fruiting body may be irregular clumps, small balls or regular pin or feather-shaped structures joined together.

Dogs vomit (Fuligo septica) is a slime mould commonly seen on sugar cane mulch.

9.7.8 Phylum Percolozoa¶

The Percolozoa are a group of colourless, non-photosynthetic protists with a feeding groove.

Many that can transform between amoeboid, flagellate, and cyst stages.

Percolozoa are bacterivores in soil, fresh water and the ocean.

The brain-eating amoeba, (Naegleria fowleri) can cause fatal amoebic meningitis.

9.8.0 Taxons¶

Taxons are the ranks used in biology classification:

Taxonomic rank: domain kingdom phylum (zoology), (division : botany) class order family genus species

Taxons are based on the Linnean sequence, Carolus Linnaeus 1707-1778, published in "Systema Naturae" in 1735.

A taxon at the rank of Division is the second highest taxonomic classification for the kingdoms Plantae (plants) and fungi.

In biology, Division is between Kingdom level and Class level.

Taxonomy, systematics, is the classification of living and extinct organisms.

(Greek taxis 'arrangement' and nomos 'law')

See:9.1.23 Classification of a rabbit

9.8.1 Classification of a common bean¶

Classification of a common bean, (Phaseolus vulgaris)

Kingdom: Plantae, Plants, Subkingdom: Tracheobionta, Vascular plants

Superdivision: Spermatophyta, Seed plants

Division: Angiospermae, flowering plants

Class: Magnoliopsida, Dicotyledons, Subclass: Rosidae

Order: Fabales, also called Leguminales

Family: Fabaceae, also called Leguminosae, Pea Family

Genus and species, binomial classification: (Phaseolus vulgaris), Bean, common bean, field bean, French bean, garden bean, green bean

(pole bean, climbing bean, bushy bean), haricot bean, kidney bean, runner bean, snap bean, string bean

Based on Classification from the National Libraryof Medicine, USA

String bean, Phaseolus vulgaris, the common bean, kidney bean, string bean, field bean, flageolet bean, French bean, garden bean, haricot bean, snap bean

It is a herbaceous annual plant grown worldwide for its edible fruit, either the dry seed or the unripe fruit, both of which are referred to as beans.

The leaf is also occasionally used as a vegetable, and the straw can be used for fodder.

The bean genus (Phaseolus), is classified into the legume family (Fabaceae), most acquire nitrogen through rhizobia, a species of nitrogen-fixing bacteria.

Classification: Eukaryota; Viridiplantae; Streptophyta; Magnoliopsida; Fabales; Fabaceae; Phaseolus

A plant genus in the family Fabaceae, which is the source of edible beans and the lectin phytohemagglutinins.

9.9.0 Phylum Metamonada¶

Metamonada flagellates have no mitochondria

(Giardia lamblia) causes "beaver fever", in termite guts to assist the breakdown of cellulose.

(Trichomonas vaginalis) causes trichomoniasis, one of the most prevalent non-viral sexually transmitted infections (STIs) in the US.

(Trimastix pyriformis) is free-living, has four flagella and consumes bacteria.

9.9.6 Wolbachia bacteria, sterilized mosquito trial¶

Mosquito repellents:

Allethrin, C19H26O3, Bioallethrin, is a mixture of two allethrin isomers, a synthetic pyrethroid, with low mammalian toxicity.
Oil of citronella, from (Cymbopogon winterianus) or (Cymbopogon nardus) is used for its aromatic properties, and as an insect repellant.

Sterilized mosquito trial

This breakthrough could support the suppression and potential eradication of Aedes aegypti worldwide.

The landmark trial involved releasing three million male Aedes aegypti mosquitoes in Northern Queensland, sterilised Wolbachia bacteria.

The sterile male insects search out and mate with wild females, preventing the production of offspring.

Scientists returned the following year and found one of the trial sites, Mourilyan in Queensland, was almost devoid of mosquitoes.

CSIRO scientist Professor Nigel Beebe, said the trial demonstrates this technique is capable of effectively suppressing mosquito populations.

“During the trial, we saw over 80 % of the mosquito population suppressed across our three trial sites.

The following year, the suppression was still in effect, with 97 % reduction of Aedes aegypti.

One year on, the mosquito population at the second trial site remained substantially suppressed, while the population fully recovered at the third site.

The technique can also be used to remove the virus-transmitting Asian tiger mosquito, Aedes albopictus, in the Torres Strait Islands.

9.10.0 Phylum Amoebozoa¶

Phylum Amoebozoa (Phylum Rhizopoda)

9.10.1 Phylum Amoebozoa, (Amoeba proteus)¶

Amoeba proteus is a single cell, aquatic, organism that is constantly changing shape.

The cytoplasm consists of clear jelly-like ectoplasm and granular endoplasm.

A clear rounded area, contractile vacuole, expands and contracts as it collects and expels water to maintain the concentration of the cytoplasm.

A central nucleus controls all the activities.

It moves by forming a pseudopodium (false foot), by the endoplasm flowing into the ectoplasm.

The amoeba flows into the pseudopodium which may be anchored to the substrate by the outer membrane, pellicle or plasma lemma, becoming sticky.

Amoeba feeds on small organisms by flowing around them and enclosing them in a food vacuole, where they are digested.

Reproduction is by simple binary fission, when the amoeba splits into two.

Amoeba avoids dry conditions by forming a spore with an external cyst wall.

Entamoeba species have no contractile vacuole possibly, because the live as parasites in vertebrates.

They have only one or two large blunt pseudopodia.

9.10.2 Phylum Amoebozoa, (Entamoeba coli)¶

(Entamoeba coli) lives in human large intestine, feeding on bacteria and remains of digested food, commensal parasite and is harmless.

It may have up to 8 nuclei when it divides inside a cyst in the faeces.

Infection occurs after ingestion of cysts in fecally-contaminated food or water.

In the small intestine, the cysts break open to release sporozoan trophozoites, which migrate to the large intestine, absorb nutrients, grow and multiply to form cysts.

Do not confuse with:

Escherichia, Phylum Proteobacteria, Escherichia coli (E. coli), the names are similar

Phylum Amoebozoa, (Entamoeba histolytica)¶

(Entamoeba histolytica), causes amoebic dysentery when it attacks the mucous membrane of the intestine, causing blood in stools and peritonitis.

It may also cause abscesses in the liver.

It has 4 nuclei, but no mitochondria.

Entamoeba histolytica causes about 50 million infections world wide, with a death rate of over 100, 000 annually.

Wheatley trichrome staining of the trophozoites, (growing stage when it is absorbing nutrients from the host), is commonly used for diagnosis of amoebic dysentery

Entamoeba histolytica in microscopic faeces specimens, looks like Entamoeba coli.

9.10.5 Phylum Myxomycota¶

Myxomycota, (acellular or plasmodial or coenocytic slime moulds)

It is a plasmodium, slime fungus, fungus-like slime moulds.

Most Myxomycota are not fungi.

The Class also includes the giant kelps, e.g. Stemonitis, Physarum polycephalum!

9.10.6 Phylum Percolozoa¶

9.10.0 Phylum Mollusca (molluscs)

Phylum Platyhelminthes (flatworms)

9.11.0 Phylum Ciliophora¶

Ciliophora, ciliates (have cilia), Balantidium, Colpoda, Paramecium, Tetrahymena, Vorticella

Flagellate protozoa (formerly a class of phylum Mastigophora)

Phytoflagellates (have chloroplasts)

Zooflagellates (do not have chloroplasts)

Examples: Balantidium, Paramecium, Stentor, Stylonychia, Vorticella

9.12.0 Eucaryota and Prokaryota¶

Eukaryota, (Greek eu 'good', and karuon 'nut')

Eukaryotes have a cell nucleus and nuclear membrane, + organelles, e.g. chromosomes, mitochondria, golgi apparatus.

Eukaryote, Eukaryota, multicellular, cells have nucleus, contain all the animals, plants, fungi, and some unicellular organisms

Most organisms are eukaryotes, except bacteria.

All multicellular organisms are eukaryotes.

Eucaryota:

Kingdom Protista

Kingdom Plantae

Kingdom Fungi

Kingdom Animalia

Prokaryota:

Prokaryotes are unicellular, cell has no nucleus, no membrane-bound organelles, no mitochondria.

Prokaryotes contain Bacteria (formerly Eubacteria), and Archaea (formerly Archaebacteria)

"9.13.0 Algae¶

Algae are simple, non-flowering, and typically aquatic plants of a large group that includes the seaweeds and many single-celled forms.

Algae contain chlorophyll, but lack true stems, roots, leaves, and vascular tissue.

Euglenophyta, e.g. Euglena.

Chrysophyta, golden algae.

Pyrrophyta, fire algae, luciferin.

Chlorophyta, Phaeophyta, and Rhodophyta.

Protists

Sacordina (protists that move using pseudopod).

Mastigophora (protists that move using flagella).

Ciliaphora (protists that move using cilia), and Sporozoa (protists that form spores).

As for the plant-like protists (Subkingdom Phycobionta), there are also various phyla: Euglenophyta, Chrysophyta (diatoms), Pyrrophyta (dinoflagellates).

Chlorophyta (green algae), Phaeophyta (brown algae), and Rhodophyta (red algae).

The Cyanophyta or blue-green algae, which are prokaryotic organisms, are traditionally included in this group but in recent classification, they are now grouped together with bacteria under Kingdom Monera.

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