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Life Science 11 - Animal Kingdom

Animal Kingdom General Characteristics:

  • All organisms are eukaryotic.

  • They are all multicellular.

  • Their cells have no cell walls. 

  • They are heterotrophic.

Phylum Porifera (Sponge)

  • Simplest multicellular animals.

  • Habitats: marine habitats and a few are in fresh water. 

  • Have pores all over the body.

  • Have a canal system that helps in circulating water and food particles and oxygen. 

  • The body design shows minimal differentiation and division of tissues.

  • Examples: Spongilla and Sycon.

  • Reproduction: sexually and asexually by budding and fragmentation.

Phylum Cnidarians

  • These organisms show more body differentiation.

  • They live in water.

  • The body has a sac-like cavity with a single opening for ingestion and Egestion

  • Cnidarians have a unique feature: stinging cells called cnidocytes. 

  • Have the ability to reorganize and regenerate their bodies 

  • Examples: Jellyfish, Sea Anemone, and Hydra.

Phylum Platyhelminthes (flatworms)

  • They are a group of soft-bodied invertebrate animals.

  • Around 20,000 species of these animals.

  • A few of these live as parasites on humans and other animals. So they do cause some amount of trouble for the host animal. 

  • A few species can be a major cause of certain diseases. For example bilharzia, a disease caused by these parasitic flatworms. 

  • As the body does not have any cavity, they are flat. The body is also not segmented and they do not have specialized systems

  • The animals in this phylum have a diverse range in size. Some are microscopic, while a few go up to two feet long.

  • They are also hermaphrodites, which mean that both sexes are present in the same organism.

  • Reproduction: sexually by fusion of gametes and asexually by fission and regeneration.

Phylum Nematoda (roundworms)

  • Are very abundant. It has more than 80,000 known species. 

  • Are bilaterally symmetrical.

  • Their body plan is simple. 

  • Surrounded by a strong, flexible non-cellular layer called a cuticle. The cuticle is secreted by and covers a layer of epidermal cells.

  • Near the body wall but under the epidermal cells are muscle cells; they run in the longitudinal direction only. A true coelom (main body cavity ) Nematodes move by contraction of the longitudinal muscles. No cilia or flagella are present.

  • They reproduce sexually by sperm and eggs by male and female adults

  • Free-living worms are found mainly in freshwater habitats. Some live in soil, food, and humans.

  • They Feed on bacteria, fungi, protozoans, or decaying organic matter.

  • By breaking down organic matter, they play an important role in the carbon cycle.

Phylum Annelida (ringed worms)

  • Over 17,000 species.

  • Exist in marine waters, fresh waters, and also in moist terrestrial areas.

  • The size of the annelids can range from a few millimeters to three meters in length.

  • The Australian earthworm measures around 3 meters. 

  • Annelids exhibit bilateral symmetry and are invertebrate organisms.

  • Reproduction: sexual and asexual (Some have female, and male organs).

  • Examples: Leeches, Earthworms, and bobbit worms.

Phylum Arthropoda

  • Over 85 percent of all known animal species are arthropods.

  • The body is divided into the head, thorax, and abdomen.

  • Joint-legged animals include insects, spiders, ants, bees, crabs, shrimps, etc.

  • Are successful in the wild because of their exoskeleton. It gives them flexibility, mobility, and protection.

  • Live on land and water.

  • They’re a source of food for many animals and human beings.

  • Reproduction: sexual

  • Major classes compare the number of body regions, legs, and antennae.

Phylum Mollusca

  • Many have a calciferous shell. 

  • Invertebrates, with bodies very soft and are covered by the hard exoskeleton.

  • Can be found in terrestrial regions and in the depths of the sea

  • Size can range from 20 meters to one millimeter, with a few microscopic animals too. 

  • They are a source of food as well as jewelry.

  • Pearls that are obtained from bivalves and gastropods are valuable as these pearls are lined with nacre. 

  • Reproduction: sexual

  • Organ level of organization.

  • Examples can be snails, slugs and oysters.

Phylum Echinodermata(sea stars)

  • They have a star-like appearance and are spherical or elongated.

  • They are exclusively marine animals.

  • Are spiny-skinned.

  • Organ system level of organization. Most members have a circulatory system as well as a digestive system.

  • They respire through the gills

  • The body is unsegmented with no distinct head.

  • The mouth is present on the ventral side while the anus is on the dorsal side.

  • The tube feet aid in locomotion.

  • Fertilization is external. 

  • Reproduction: sexual and asexual

Phylum Protochordata

  • They are generally found in marine water.

  • Their body is bilaterally symmetrical, triploblastic, and coelomated.

  • Lack a head, skull, vertebral column, and brain.

  • Organ system level of organization.

Phylum Vertebrata

Mammals (Class Mammalia)

  • Ability to regulate their body temperature irrespective of the surrounding ambient temperature. (endothermic)

  • Female mammals produce milk. 

  • Almost all mammals give birth.

Birds (Class Aves)

  • Characterized by feathers and toothless beaks.

  • High metabolic rate.

  • Lay hard-shelled eggs.

3- Reptiles (Class Reptilia)

  • Include tetrapods such as snakes, crocodiles, and turtles.

  • Characterized by being ectothermic.

  • Snakes are still considered tetrapods though they have no visible limbs, as they evolved from ancestors that had limbs.

  • Most reptiles today are cold-blooded

4- Amphibians (Class Amphibia)

  • Characterized by breeding behavior.

  • Most need a body of water to breed as their eggs are shell-less.

  • They undergo metamorphosis where the young ones transform from fully aquatic larval form (with gills and fins) to terrestrial adult form.

5- Bony fishes (Class Osteichthyes)

  • Characterized by their skeleton which is composed primarily of bone rather than cartilage

  • Largest class of vertebrates today.

6- Cartilaginous fishes (Class Chondrichthyes)

  • Characterized by the cartilaginous skeleton.

  • Members include sharks, rays, skates, and sawfish. 

7-Jawless fishes (Class Agnatha)

  • They have a jawless, circular mouth.

  • Have rows of small sharp which aid in holding and feeding on other fishes.

  • Most members of this class are parasites and scavengers.

Life Science 11 - Animal Kingdom

Animal Kingdom General Characteristics:

  • All organisms are eukaryotic.

  • They are all multicellular.

  • Their cells have no cell walls. 

  • They are heterotrophic.

Phylum Porifera (Sponge)

  • Simplest multicellular animals.

  • Habitats: marine habitats and a few are in fresh water. 

  • Have pores all over the body.

  • Have a canal system that helps in circulating water and food particles and oxygen. 

  • The body design shows minimal differentiation and division of tissues.

  • Examples: Spongilla and Sycon.

  • Reproduction: sexually and asexually by budding and fragmentation.

Phylum Cnidarians

  • These organisms show more body differentiation.

  • They live in water.

  • The body has a sac-like cavity with a single opening for ingestion and Egestion

  • Cnidarians have a unique feature: stinging cells called cnidocytes. 

  • Have the ability to reorganize and regenerate their bodies 

  • Examples: Jellyfish, Sea Anemone, and Hydra.

Phylum Platyhelminthes (flatworms)

  • They are a group of soft-bodied invertebrate animals.

  • Around 20,000 species of these animals.

  • A few of these live as parasites on humans and other animals. So they do cause some amount of trouble for the host animal. 

  • A few species can be a major cause of certain diseases. For example bilharzia, a disease caused by these parasitic flatworms. 

  • As the body does not have any cavity, they are flat. The body is also not segmented and they do not have specialized systems

  • The animals in this phylum have a diverse range in size. Some are microscopic, while a few go up to two feet long.

  • They are also hermaphrodites, which mean that both sexes are present in the same organism.

  • Reproduction: sexually by fusion of gametes and asexually by fission and regeneration.

Phylum Nematoda (roundworms)

  • Are very abundant. It has more than 80,000 known species. 

  • Are bilaterally symmetrical.

  • Their body plan is simple. 

  • Surrounded by a strong, flexible non-cellular layer called a cuticle. The cuticle is secreted by and covers a layer of epidermal cells.

  • Near the body wall but under the epidermal cells are muscle cells; they run in the longitudinal direction only. A true coelom (main body cavity ) Nematodes move by contraction of the longitudinal muscles. No cilia or flagella are present.

  • They reproduce sexually by sperm and eggs by male and female adults

  • Free-living worms are found mainly in freshwater habitats. Some live in soil, food, and humans.

  • They Feed on bacteria, fungi, protozoans, or decaying organic matter.

  • By breaking down organic matter, they play an important role in the carbon cycle.

Phylum Annelida (ringed worms)

  • Over 17,000 species.

  • Exist in marine waters, fresh waters, and also in moist terrestrial areas.

  • The size of the annelids can range from a few millimeters to three meters in length.

  • The Australian earthworm measures around 3 meters. 

  • Annelids exhibit bilateral symmetry and are invertebrate organisms.

  • Reproduction: sexual and asexual (Some have female, and male organs).

  • Examples: Leeches, Earthworms, and bobbit worms.

Phylum Arthropoda

  • Over 85 percent of all known animal species are arthropods.

  • The body is divided into the head, thorax, and abdomen.

  • Joint-legged animals include insects, spiders, ants, bees, crabs, shrimps, etc.

  • Are successful in the wild because of their exoskeleton. It gives them flexibility, mobility, and protection.

  • Live on land and water.

  • They’re a source of food for many animals and human beings.

  • Reproduction: sexual

  • Major classes compare the number of body regions, legs, and antennae.

Phylum Mollusca

  • Many have a calciferous shell. 

  • Invertebrates, with bodies very soft and are covered by the hard exoskeleton.

  • Can be found in terrestrial regions and in the depths of the sea

  • Size can range from 20 meters to one millimeter, with a few microscopic animals too. 

  • They are a source of food as well as jewelry.

  • Pearls that are obtained from bivalves and gastropods are valuable as these pearls are lined with nacre. 

  • Reproduction: sexual

  • Organ level of organization.

  • Examples can be snails, slugs and oysters.

Phylum Echinodermata(sea stars)

  • They have a star-like appearance and are spherical or elongated.

  • They are exclusively marine animals.

  • Are spiny-skinned.

  • Organ system level of organization. Most members have a circulatory system as well as a digestive system.

  • They respire through the gills

  • The body is unsegmented with no distinct head.

  • The mouth is present on the ventral side while the anus is on the dorsal side.

  • The tube feet aid in locomotion.

  • Fertilization is external. 

  • Reproduction: sexual and asexual

Phylum Protochordata

  • They are generally found in marine water.

  • Their body is bilaterally symmetrical, triploblastic, and coelomated.

  • Lack a head, skull, vertebral column, and brain.

  • Organ system level of organization.

Phylum Vertebrata

Mammals (Class Mammalia)

  • Ability to regulate their body temperature irrespective of the surrounding ambient temperature. (endothermic)

  • Female mammals produce milk. 

  • Almost all mammals give birth.

Birds (Class Aves)

  • Characterized by feathers and toothless beaks.

  • High metabolic rate.

  • Lay hard-shelled eggs.

3- Reptiles (Class Reptilia)

  • Include tetrapods such as snakes, crocodiles, and turtles.

  • Characterized by being ectothermic.

  • Snakes are still considered tetrapods though they have no visible limbs, as they evolved from ancestors that had limbs.

  • Most reptiles today are cold-blooded

4- Amphibians (Class Amphibia)

  • Characterized by breeding behavior.

  • Most need a body of water to breed as their eggs are shell-less.

  • They undergo metamorphosis where the young ones transform from fully aquatic larval form (with gills and fins) to terrestrial adult form.

5- Bony fishes (Class Osteichthyes)

  • Characterized by their skeleton which is composed primarily of bone rather than cartilage

  • Largest class of vertebrates today.

6- Cartilaginous fishes (Class Chondrichthyes)

  • Characterized by the cartilaginous skeleton.

  • Members include sharks, rays, skates, and sawfish. 

7-Jawless fishes (Class Agnatha)

  • They have a jawless, circular mouth.

  • Have rows of small sharp which aid in holding and feeding on other fishes.

  • Most members of this class are parasites and scavengers.