Golden Key Points -Chapter4-Animal Kingdom

Golden Key Points

Phylum – Porifera:

Primitive multicellular organisms.

Lack true tissues and organs.

• Filter-feeding through collar cells (choanocytes).
• Asymmetrical or radially symmetrical body.
• Hermaphroditic with internal fertilization.
• Examples: Sponges like Sycon, Spongilla.

Phylum – Coelenterata (Cnidaria):

• Radially symmetrical aquatic organisms.
• Possess specialized stinging cells called cnidocytes.
• Two basic body forms: polyp and medusa.
• Mostly carnivorous.
• Examples: Jellyfish, coral, sea anemones.

Phylum – Ctenophora:

• Radially symmetrical marine organisms.
• Unique comb rows for locomotion.
• Bioluminescent properties.
• Mostly carnivorous.
• Examples: Comb jellies like Pleurobrachia.

Phylum – Platyhelminthes:

• Dorso-ventrally flattened body.
• Unsegmented with organ-level organization.
• Parasitic and free-living species.
• Examples: Tapeworms, flatworms.

Phylum – Aschelminthes:

• Roundworms with cylindrical body shape.
• Complete digestive system.
• Pseudocoelomate body plan.
• Examples: Roundworms like Ascaris.

Phylum – Annelida:

• Segmented worms with coelomate body plan.
• Closed circulatory system.
• Exhibit metamerism (segmentation).
• Examples: Earthworms, leeches.

Phylum – Arthropoda:

• Largest phylum with jointed appendages.
• Exoskeleton made of chitin.
• Segmented body with specialized body regions.
• Examples: Insects, arachnids, crustaceans.

Phylum – Mollusca:

• Soft-bodied organisms with a muscular foot and mantle.
• Most possess a hard shell.
• Radula for feeding in many species.
• Examples: Snails, clams, octopuses.

Phylum – Echinodermata:

• Marine organisms with spiny endoskeleton.
• Unique water vascular system for locomotion and feeding.
• Regeneration ability.
• Examples: Starfish, sea urchins.

Phylum – Chordata:

• Possess a notochord at some stage of life.
• Bilaterally symmetrical with dorsal nerve cord.
• Includes subphyla Urochordata, Cephalochordata, and Vertebrata.
• Examples: Fish, amphibians, mammals.

Class – Cyclostomata:

• Jawless fish with circular mouth.
• External parasites on other fish.
• Examples: Lampreys, hagfish.

Class – Chondrichthyes:

• Cartilaginous fish with tooth-like scales.
• Lack swim bladder, maintain buoyancy through oily liver.
• Examples: Sharks, rays.

Class – Osteichthyes:

• Bony fish with swim bladder for buoyancy.
• Most have gills covered by an operculum.
• Examples: Trout, tuna, goldfish.

Class – Reptilia:

• Terrestrial vertebrates with dry, scaly skin.
• Most lay shelled eggs.
• Examples: Snakes, lizards, crocodiles.

Class – Aves:

• Warm-blooded vertebrates with feathers.
• Most have the ability to fly.
• Examples: Birds like sparrows, eagles, penguins.

Class – Mammalia:

• Warm-blooded vertebrates with mammary glands.
• Hair or fur covering body.
• Most give birth to live young and nurse offspring with milk.
• Examples: Humans, dogs, whales.