Animalia Kingdom Welcome Home Animals Most diverse kingdom

Animalia Kingdom Welcome Home

Animals • Most diverse kingdom in appearance 95% = invertebrates (do not have backbone) • 5% = vertebrates (have a backbone) What is an Animal? • Heterotrophic • Eukaryotic • Multicellular • Lack cell walls

7 Essential Functions of Animals

Feeding • Herbivore = eats plants • Carnivore = eats animals • Omnivore = eats plants and animals • Detritivore = feed on decaying organic material • Filter Feeders = aquatic animals that strain food from water • Parasite = lives in or on another organism

Respiration • Take in O 2 and give off CO 2 • Small animals can undergo diffusion (exchange of O 2 and CO 2 via moist surfaces) • Larger Animals – Diffusion not enough – Specialized respiratory structures • Gills (must be kept moist) – provide large surface area for O 2 and CO 2 exchange » (mudpuppy) • Lungs (don’t need moisture) – Evolved for terrestrial

Circulation • Very small animals rely on diffusion – All cells are close enough to surface for oxygen • Larger animals have circulatory system which include vessels – Open system – Closed system

Excretion • Primary waste product is ammonia, liquid waste filtered by the kidneys

Response • Receptor cells = sound, light, external stimuli

Movement/Support • Most animals are motile (can move) • Muscles usually work with a skeleton – Endoskeleton: hard material inside – Exoskeleton: external skeleton (crabs, clams, insects)

Reproduction • Most reproduce sexually = genetic diversity Many invertebrates can also reproduce asexually = to increase their numbers rapidly In parthenogenesis ("virgin birth"), the females produce eggs, but these develop into young without ever being fertilized. Female Komodo dragons (the largest lizard) can produce offspring by parthenogenesis when no male is available for sexual reproduction

Body Symmetry • The body plan of an animal, how its parts are arranged • Asymmetry – no pattern (corals, sponges) • Radial Symmetry – shaped like a wheel (starfish, hydra, jellyfish) • Bilateral Symmetry – has a right and left side (humans, insects, cats, etc) – Major evolutionary change in animals – Enabled different parts of the body to become specialized in different ways

Bilateral Symmetry • Bilateral animals can be divided into 4 regions – Anterior (front) – Posterior (back) – Ventral (underside) – Dorsal (top)