The Animal Kingdom
BIOLOGY
9. The Animal Kingdom
Protozoa
This most primitive unicellular organisms which reproduce by fission, budding,spores or sexually. e.g. Amoeba, Entamoeba, paramecium, vorticella, plasmodium, Euglena & trypanosoma. They move a variety of ways. The ameba has a false foot that extends as it moves. The paramecium is covered with hairs and the euglena has a whip-like tail(flagella) to move. A protozoa takes in oxygen through the cell membrane and gives off carbon dioxide through the cell membrane. Some protozoans are harmful to man as they can cause serious diseases. Others are
Human Diseases Caused by protozoa
Disease
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Name of Prozoa
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Mode of transmission
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Ameobic dysentery (Amoebiasis)
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Entamoeba histolytica
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thru ingestion of cysts in drinking water and food
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Diarrhoea
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Glardia intestinalis
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thru ingestion of cysts in drinking water and food
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Kala-Azar(Black sickness)
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Leishmania donovani
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thru’ the bite of infected Sandfly
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Malaria
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Plasmodium vivax
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thru’ the bite of infected anophelise - mosquito
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Sleeping sickness
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Trypanosoma brucei
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thru’ the bite of infected tse-tse fly
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Oriental Sore or Delhi boil
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Leishmania tropica
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thru’ the bite of infected Sandfly
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Vaginitis
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Trichomonas vaginalis
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During coitus in female vagina , shared towels and toilet seats
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Porifera (Sponges)
These are most primitive of multi cellular animals. They live in water bodies. They were the first group of animals that has specialized cells to do special jobs. A sponge is a hollow tube with many pores or openings. The skeleton is made of lime or silicon. A sponge takes in food via the water that flows through the pores. Commercial sponge is only porous skeleton. e.g. Euspongia (bath sponge),sycon ,spongilla(fresh water) , hyalonema(Glass sponge).
These are most primitive of multi cellular animals. They live in water bodies. They were the first group of animals that has specialized cells to do special jobs. A sponge is a hollow tube with many pores or openings. The skeleton is made of lime or silicon. A sponge takes in food via the water that flows through the pores. Commercial sponge is only porous skeleton. e.g. Euspongia (bath sponge),sycon ,spongilla(fresh water) , hyalonema(Glass sponge).
Cnidaria (Coelenterata)
These are mostly marine species except hydra which is fresh water form. These are radially symmetrical animals which posses 2 distinct germ layers ectoderm and endoderm . Polyp and medusa are 2 basic form. Medusa is free floating and represents sexual phase of the animal. These are comparable to alteration of generation among plants. The corals consists of polyp colonies. These are soft bodied organisms having a thick calcium carbonate shell to protect it. The living coral develop on dead corals and thus coral reefs are found. Important coelentrates are coral, hydra, jellyfish, sea anemone, Portuguese man of war.
These are mostly marine species except hydra which is fresh water form. These are radially symmetrical animals which posses 2 distinct germ layers ectoderm and endoderm . Polyp and medusa are 2 basic form. Medusa is free floating and represents sexual phase of the animal. These are comparable to alteration of generation among plants. The corals consists of polyp colonies. These are soft bodied organisms having a thick calcium carbonate shell to protect it. The living coral develop on dead corals and thus coral reefs are found. Important coelentrates are coral, hydra, jellyfish, sea anemone, Portuguese man of war.
Platyhelminths(Flat worms)
Flat worm is a common name for soft bodied, usually parasitic animals, the simplest of animals possessing heads. A flatworm has a gastrovascular cavity with one opening. It takes food in and gets rid of wastes through the same opening. They are bilaterally symmetrical and somewhat flattened and are elongated. E.g. Tape worm, flukes.
Flat worm is a common name for soft bodied, usually parasitic animals, the simplest of animals possessing heads. A flatworm has a gastrovascular cavity with one opening. It takes food in and gets rid of wastes through the same opening. They are bilaterally symmetrical and somewhat flattened and are elongated. E.g. Tape worm, flukes.
Nemathelminthes(round worms)
These are roundworms which are usually found in soil, water, plants and in animals as a parasite. A roundworm has a definite digestive system that runs the length of their bodies. It has a mouth, pharynx, intestine and anus. e.g. Ascaris(round worm),oxyuris(pinworm), ancylostoma(hook worm),wucheria(Filaria worm).
These are roundworms which are usually found in soil, water, plants and in animals as a parasite. A roundworm has a definite digestive system that runs the length of their bodies. It has a mouth, pharynx, intestine and anus. e.g. Ascaris(round worm),oxyuris(pinworm), ancylostoma(hook worm),wucheria(Filaria worm).
Annelida
These are known as segmented worms whose body is made up of similar segments. A true closed circulatory system with hearts and oxygen carrying blood is found for the first time in them. A earthworm has a nervous system with a simple brain and nerve cord. Earth worms are useful in agriculture because they loosen the soil for roots to grow and its wastes help to fertilize the soil. Earthworms are hermaphroditic, possessing both male and female internal reproductive organs. Some blood sucking leech produce a compound known as Hirudin from their salivary gland to prevent blood clotting. E.g. earth worms, leech and clamworm.
These are known as segmented worms whose body is made up of similar segments. A true closed circulatory system with hearts and oxygen carrying blood is found for the first time in them. A earthworm has a nervous system with a simple brain and nerve cord. Earth worms are useful in agriculture because they loosen the soil for roots to grow and its wastes help to fertilize the soil. Earthworms are hermaphroditic, possessing both male and female internal reproductive organs. Some blood sucking leech produce a compound known as Hirudin from their salivary gland to prevent blood clotting. E.g. earth worms, leech and clamworm.
Mollusca
It is the common name for members of a phylum soft-bodied animals with a hard external shell (so called shell fishes). It is the second largest kingdom after arthropods. The three major groups are gastropods, bivalves and cephalopods.
It is the common name for members of a phylum soft-bodied animals with a hard external shell (so called shell fishes). It is the second largest kingdom after arthropods. The three major groups are gastropods, bivalves and cephalopods.
a) Gastropod: The Gastropoda (Greek gaster,"stomach"; pous,"foot") are generally characterized by a single shell and an asymmetric body. E.g. snails and slugs.
b) Bivalves: It is characterized by a shell divided into two valves hinged at one side, gills specialized for feeding, and a reduced head. E.g clam, cockle, mussel, oyster, scallop, and shipworm. Pearl is actually a secretion by bivalves induced by factors such as foreign substances etc
c) Cephalpods: The word cephalopod means "head footed," and the animals are so named because the arms surround the mouth. These are predatory marine mollusks which includes squid, octopus, and nautilus.
Arthropods
It is the largest animal kingdom. These are animals with hard outer skeleton and jointed body and limbs. The arthropods are the first animal group to have jointed legs. The major groups are
a) Insects : The largest class of arthropods. They have six legs and three body parts, a head, a thorax and an abdomen. They also have an outer or exoskeleton made of chitin, containing cellulose. All insects grow from eggs. They go through various stages until they reach adulthood. This transformation through these stages is called metamorphosis. Insects undergo either complete(butterfly, bee, ant, beetle) and fly or incomplete (dragonfly, termite, grasshopper and true bug) metamorphosis. Complete metamorphosis has four stages: egg, larvae, pupae and adult where as in incomplete metamorphosis has three stages called egg, nymph and adult. A insect has a circulatory system that carries food, but not oxygen throughout its body. Since it does not carry oxygen, insect blood is green, not red like mammal blood. The insect heart is a simple tube running along their backs.
It is the largest animal kingdom. These are animals with hard outer skeleton and jointed body and limbs. The arthropods are the first animal group to have jointed legs. The major groups are
a) Insects : The largest class of arthropods. They have six legs and three body parts, a head, a thorax and an abdomen. They also have an outer or exoskeleton made of chitin, containing cellulose. All insects grow from eggs. They go through various stages until they reach adulthood. This transformation through these stages is called metamorphosis. Insects undergo either complete(butterfly, bee, ant, beetle) and fly or incomplete (dragonfly, termite, grasshopper and true bug) metamorphosis. Complete metamorphosis has four stages: egg, larvae, pupae and adult where as in incomplete metamorphosis has three stages called egg, nymph and adult. A insect has a circulatory system that carries food, but not oxygen throughout its body. Since it does not carry oxygen, insect blood is green, not red like mammal blood. The insect heart is a simple tube running along their backs.
b) Arachnids: The annelids are similar to insects. However, they have eight legs, wings are different and they have no antenna. The arachnids are spiders, scorpions, etc.
c) Crustaceans: These are predominantly aquatic arthropods with protective carapace and compound eyes. E.g. Prawns, Lobsters and Crabs.
d) Myriapods: include millipedes and centipedes. The centipedes have two pairs of legs per segment while millipedes have one pair.
Echinoderm
It consists of phylum of marine animals such as starfish, brittle stars, sea urchins, sand dollars and sea cucumbers. They usually show a superficial five part radial symmetry. The phylum name is derived from spiny skin. A Echinoderm is a male or female. The males and females discharge their eggs and sperm into the water where they are fertilized. A female can release one hundred million eggs at once. If a piece of certain echinoderms is chopped off, a new piece or even a new echinoderm can regrow.
It consists of phylum of marine animals such as starfish, brittle stars, sea urchins, sand dollars and sea cucumbers. They usually show a superficial five part radial symmetry. The phylum name is derived from spiny skin. A Echinoderm is a male or female. The males and females discharge their eggs and sperm into the water where they are fertilized. A female can release one hundred million eggs at once. If a piece of certain echinoderms is chopped off, a new piece or even a new echinoderm can regrow.
Chordate
It refers to the common name for animals of the phylum Chordata, which includes vertebrates as well as some invertebrates that possess, at least some time in their lives, a stiff rod called notochord lying above the gut and beneath a single hollow dorsal nerve cord. It is the third largest animal phylum. The Phylum chordate has been divided into Proto chordate and Vertebrate.
I) Proto Chordate: They are primitive lower chordates possess notochord but lacks vertebral column or back bone. They are represented by cephalo chordates e.g. small marine fish (Amphioxus), urochordata (Ascidian) and Hemichordata (Balanoglossus)
II) Vertebrate: It represents the largest group of chordates.
It refers to the common name for animals of the phylum Chordata, which includes vertebrates as well as some invertebrates that possess, at least some time in their lives, a stiff rod called notochord lying above the gut and beneath a single hollow dorsal nerve cord. It is the third largest animal phylum. The Phylum chordate has been divided into Proto chordate and Vertebrate.
I) Proto Chordate: They are primitive lower chordates possess notochord but lacks vertebral column or back bone. They are represented by cephalo chordates e.g. small marine fish (Amphioxus), urochordata (Ascidian) and Hemichordata (Balanoglossus)
II) Vertebrate: It represents the largest group of chordates.
i) Agnatha: They are fish like forms with the absence of Jaws and scales. Their skeleton is cartilaginous. The best examples of this type are lamprey and the hagfish They have two chambered heart and gills used for respiration.
ii) Gnathostomata: These are vertebrates with jawed mouth. These are subdivided into fishes, amphibians, reptiles, birds and mammals.
a) Fishes: These are diverse group of cold blooded animals that live and breathe in water. Most fish have gills for breathing, two chambered heart, fins for swimming, scales for protection, and a streamlined body for moving easily through the water. The swim (or gas) bladder allows fish to maintain a constant buoyancy regardless of the changing water pressure at varying depths. Its eyes are positioned on either side of its body and are quite large, with no eyelid. They have an inner ear but no outer ear opening. Fishes are broadly classified into
i) Chondrichthyes (Cartilaginous fish): Their skeleton made of cartilage and their body covered with triangular Placoid scales. They lack a swim bladder but have air sacs to regulate buyonancy. E.g Sharks ,Rays and Skates. Sharks are viviparous.
ii) Osteichthyes (bony fishes): They have a bony endoskeleton. These are oviparous and fertilization is external. E.g. Salmon, Labeo (rohu), Mrigal etc.
b) Amphibians: Amphibian means both sides of life. it begins its life in the water and then finishes it mainly on land. It uses gills in larval stage (tadpole) and lungs and skins in the adult stage. Their heart is three chambered. Skin is often kept moist for gas exchange. These are cold blooded animals and have to be near water to complete their life cycle. So these are severely affected by environmental pollutants, destruction and modification of amphibian habitats, such as the cutting of forests and the draining of wetlands .E.g. Frogs, toad, Salamander, caecilians, sirens etc.
c) Reptiles: Reptiles are cold blooded animal with tough, dry skin covered with horny scales adapted for life in dry places. Some forms are aquatic. Reptiles breathe air with lungs alone. They have teeth except in tortoises and turtles. They have three chambered heart (crocodile has a four chambered heart). The females eggs are fertilized in her body by the male. The eggs are laid in a shell that has a leathery covering to protect it in the wilds. E.g. turtles, lizards, snakes, crocodiles, gavial (Gharial),alligators and dinosaurs.
d) Birds: They are unique in the fact that they are covered with feathers and fly. They are descended from reptiles, feathers are modified limbs and their eggs resemble reptilian eggs. But like mammals they are warm blooded and have four chambered heart. The bones of many adult birds are hollow rather than filled with marrow, making them lighter and enabling them to disperse heat in flight. A bird has relatively large eyes that allow it to judge distance well and an excellent sense of hearing. They exhibit migratory behaviour, nest building and parental care. The study of birds is ornithology. The Smallest bird is humming bird. The heaviest bird is bustard
e) Mammals: Mammals are warm blooded animals having distinctive characteristics such as milk producing mammary glands, hair on their body, external ears, sweat glands, give birth to young rather laying eggs and nurse their young
Major mammal groups
Egg Laying Mammals
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platypus and anteater
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Flying Mammals
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bats
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Toothless Mammals
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sloth, armadillo and and anteater
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Pouched Mammals (marusupials)
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kangaroo, koala, opossum and wallaby
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Flesh-eating Mammals
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bear and the raccoon - Flat-footed; cats, dogs, lions, tigers, wolves and coyotes – walk on their toes; skunk, weasel, otter and mink walk partly on their toes and partly on soles
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Flexibly Fingered Mammals (Primates)
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monkey, lemur, orangetan, chimpanzee, gorilla, gibbon and man
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Insect Eating Mammals (insectivores)
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mole, shrew and hedgehog
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Gnawing Mammals (Rodents)
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the rat, mouse, squirrel, chipmunk, prairie dog, rabbit, hare and beaver
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Hoofed Mammals (Ungulates)
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Even toed cud chewers - cow, sheep, goat, camel, giraffe and deer even-toed noncud chewers- pig and the hippopotamus
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Trunk Nosed Mammals
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elephant
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Marine Mammals
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whale, dolphin and porpoise
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