Kingdom Animalia General Characteristics Eukaryotic Multicellular No cell

Kingdom Animalia

General Characteristics • • Eukaryotic Multicellular No cell walls Move to find the following: – Food – Shelter – Protection – Mates

General Characteristics (continued) • Heterotrophs – eat other organisms for energy – Omnivore (plants & animals) – Carnivore (animals only) – Herbivore (plants only)

General Characteristics (continued) • Digest their food because food must be broken down to fit inside the cells for metabolizing

Classification – 9 major phyla • Porifera – animals have holes throughout their body (Ex: Sponges) • Cnidaria – animals with soft bodies and cnidocytes = stinging cells (Ex: jellyfish, hydra, sea anemone, coral) • Platyhelminthes – flat worms (Ex: planarians, tapeworms) • Nematoda – round worms (Ex: heartworm, trichinella, pin worms) • Mollusca – mollusks (Ex: snails, slugs, clams, oysters, octopus, squid) • Annelida – segmented worms (Ex: earthworm & leeches) • Arthropoda – insects, crustaceans, arachnids • Echinodermata – spiny skinned animals (Ex: Sea star) • Chordata – animals with a backbone = Vertebrates

Origin of Invertebrates • Between 610 – 570 MYA (millions of years ago): First eukaryotic, MULTICELLULAR organisms • Most likely flat, plate-shaped organisms with soft bodies that absorbed nutrients from their water environments (possibly lived in symbiotic relationships with photosynthetic algae) • Bilateral symmetry and possible segmentation • Very little cell specialization or body organization

The Cambrian Period • Explosion of Animals • Began 544 MYA • Evolution of shells, skeletons, and other hard outer coverings • More specialized cells, tissue and the beginnings of organ systems • Body symmetry, segmentation, some of type of skeleton, anterior & posterior ends and appendages for specific functions

Cladogram of Invertebrate Evolution Phylum Cnidaria: Cnidarians Phylum Platyhelminthes: Flatworms Phylum Nematoda: Roundworms Phylum Mollusca: Mollusks Phylum Echinodermata: Echinoderms Phylum Annelida: Annelids Phylum Arthropoda: Arthropods Radial Symmetry Phylum Porifera: Sponges Pseudocoelom Radial Symmetry Protostome Development Three Germ Layers; Bilateral Symmetry Tissues Single-celled ancestor Phylum Chordata: Chordates Multicellularity Deuterostome Development Coelom

Evolutionary Trends Specialized Cells, Tissues & Organs 1. PORIFERA & CNIDARIA: No tissues, organs nor organ systems – just specialized cells Germ Layers: Porifera (sponges) – 0 Cnidaria (jellyfish, coral, sea anemone) – 2 2. WORMS: First Appearance of Organs & Organ Systems Germ Layers: 3 Platyhelminthes (planarians & tapeworms) Nematoda (hookworm, heartworm, pinworm) Annelida (earthworm & leeches) Mollusca (snails, slugs, clams, squid, octopus) Arthropoda (insects, arachnids, centipedes, shrimp, lobster) Echinodermata (sea star, sand dollar) Chordata (vertebrates) Body Symmetry – Asymmetry: Porifera – Radial: Cnidaria & Echinodermata – Bilateral: Platyhelminthes, Nematoda, Annelida, Mollusca, Arthropoda & Chordata

Evolutionary Trends (continued) Cephalization – Concentration of nerve cells at the anterior end of the animal – Evolved with bilateral symmetry – Began with GANGLIA in WORMS – Eventually, the evolution of the BRAIN starting in MOLLUSKS and ARTHROPODS Coelom (BODY CAVITY) Formation – Evolved with the development of 3 germ layers – ACOELOMATES: no body cavity • PORIFERA • CNIDARIA • PLATYHELMINTHES (flatworms) – PSEUDOCOELOMATES: partial body cavity • NEMATODA (roundworms) – COELOMATES: true body cavity • • • ANNELIDA MOLLUSCA ARTHROPODA ECHINODERMATA CHORDATA Embryology – Protostomes (mouth before anus): SPONGES to ARTHROPODS – Deuterostomes (anus before mouth): ECHINODERMS & CHORDATES

Body Plans • Asymmetry = no definite shape (sponge) • Radial Symmetry = circle body plan with a central point (sea star, jellyfish, sand dollar, hydra) • Bilateral Symmetry = 2 sides of the body are arranged in the same way; the 2 sides of the body are almost mirror images of each other (most animals have this type of symmetry)

Body Directions • Dorsal side = backside of animal (darker) • Ventral side = belly-side of animal • Lateral = left and right side of the animal; away from the midline • Medial- Toward the midline • Anterior end = head end (cephalization – concentration of nerve cells at the anterior end of the animal which results in the formation of a true brain) • Posterior end = tail end

Early Development of Animals • Fertilized egg = Zygote • Zygote Embryo • Embryo continues to divide to become a BLASTULA (hollow ball of cells) • The Blastula folds creating an opening called a BLASTOPORE = called GASTRULATION • Blastopore leads to a tube which will become the following: – Protostomes: mouth- ex. earthworm – Deuterostomes: anus- ex. echinoderms

Blastulation & Gastrulation

Germ Layers • Endoderm (innermost germ layer): gives rise to the lining of the digestive & respiratory tract • Mesoderm (middle germ layer): gives rise to muscles, circulatory, reproductive and excretory systems • Ectoderm (outermost germ layer): gives rise to sensory organs, nerves, integumentary system (skin, hair, nails, etc. )

Germ Layers

Porifera • • • Hollow tube body plan: ACOELOMATE – no coelom Contains pores (holes) throughout body No tissue, organs and organ systems Live in water Asymmetry As adults sponges are SESSILE – attach to one place & do not move for the rest of its life Filter feeders Reproduce asexually and sexually – HERMAPHRODITES (have both male & female reproductive organs) – external fertilization Water goes into pores and out the OSCULUM Ectoderm (outside) can be made of soft, flexible material called spongin or hard, spiky material called spicules

Porifera Chart • • No Germ Layers No cephalization Acoelomate Circulatory: Diffusion Digestive: Filter Feeders Nervous System: None; Produces Toxins Excretory System- Diffusion Reproductive: Sexually/Internal Fertilization or Asexually via budding and gemmules • Respiratory System: Diffusion • Movement: Sessile as Adults

Cnidaria • Soft bodies • Tentacles with cnidocytes = stinging cells • Inside each cnidocyte is a nematocyst = coiled barbed stinger with poison • Cnidocytes are triggered by touch • Used to paralyze & capture prey • Radial symmetry • Contain tissue • Acoelomates • Digestive cavity that breaks down food using enzymes • Mouth • No circulatory/respiratory systems • Simple nervous system called Nerve Net or Nerve Ring • 2 Body types – Medusa (moves) & Polyp (sessile) • Sexually reproduce – hermaphrodites – external fertilization

Classes of Cnidaria • Class Hydrozoa – hydra, man of war • Class Scyphozoa – jellyfish • Class Anthozoa – sea anemone & coral

Cnidocyte Being Triggered

Cnidarians Chart • • • Germ layers: 2 Symmetry: Radial No Cephalization Acoelomate Circulatory: Diffusion Digestive/ Feeding: 1 opening with gastrovascular cavity Nervous: specialized cells- simple system called nerve net Excretory: Diffusion Reproductive: sexually/ separate sexes/external fertilizationasexually via budding • Respiratory: Diffusion • Movement: Medusa (moves with current) or Polyp (sessile)

Worms • Invertebrates with soft bodies • Bilateral symmetry • Tissue, organs, organ systems • 3 types: – Flat – Round – Segmented

Platyhelminthes • • • Platy = flat, helminthe = worm Free-living = planarian Parasites = tapeworm Has the first primitive excretory system called FLAME BULB CELLS = removal of ammonia (urea = higher forms of animals) No circulatory/respiratory system – get oxygen & nutrients thru osmosis & diffusion Digestive system = intestines for digesting food Have one opening that serves as both mouth and anus Sexually reproduction – hermaphrodites – internal fertilization Can regenerate

Examples of Flatworms Tapeworms

Platyhelminthes Chart • • Germ layers: 3 Symmetry: Bilateral Cephalization Present Acoelomate Circulatory: Diffusion- No internal transport system Digestive/ Feeding: 1 opening with digestive cavity and pharynx Nervous: ganglia groups of nerve cells and eyespots Excretory: Flame cells that remove excess water and metabolize waste (ammonia) • Reproductive: sexually/hermaphrodites –asexually via fission • Respiratory: Diffusion • Movement: Turbellians use cilia to move while parasitic worms rely on the host's circulation

Nematoda • • • Round worms Largest phylum of worms (in number) Some free-living, some parasitic Live in soil, fresh & salt water, animals Has a tube within a tube body plan Has a complete digestive tract with a separate mouth and anus (pseudocoelom) • No circulatory/respiratory system • Sexual reproduction – internal fertilization

Examples • Hookworm • Ascaris (pinworm-live in the intestine of its hosts) • Trichinella (found in the muscles of pigs) • Filarial Worms (live in blood & lymph vessels of birds and mammals) • Heartworm

PARASITIC ROUNDWORMS

Nematoda Chart • • • Germ layers: 3 Symmetry: Bilateral Cephalization Present Pseudocoelomate Circulatory: Diffusion- No internal transport system Digestive/ Feeding: 2 openings- complete Nervous: simple nervous system and several ganglia Excretory: diffusion Reproductive: sexually/individual sexes/internal fertilization Respiratory: Diffusion Movement: undulatory; nematodes are poor swimmers and usually require contact with a substrate to move.

Mollusca • Soft-bodied invertebrates that usually have shells (valves) • Live on land, fresh & salt water • Bilateral symmetry • Has a true coelom = cavity where all the organs are held • Common body parts: – Mantle = thin tissue that covers soft body – Mantle cavity = where the gills are located – Visceral mass = coelom (gut) where all the organs are held – Foot = strong muscle used for movement • 1 st group of animals to have a circulatory & respiratory system (heart & gills) • 2 types of circulatory systems: CLOSED (vessels) & OPEN (no vessels)

Classes of Mollusks • Univalves or Gastropods (snails, slugs) • Bivalves (clams, oysters, mussels, scallops = adductor muscles of clams) • Cephalopods (octopus, squid) – complex nervous system – centralized with a true brain, closed circulatory system, stream-lined to move quickly, very smart

Mollusca Chart • • • Germ layers: 3 Symmetry: Bilateral Cephalization Present True Coelom Circulatory: Slow Moving- Open and Fast Moving- Closed Digestive/ Feeding: herbivores, omnivores, filter-feeders, detritivores, parasites/ radula tongue with teeth Nervous: bivalves: simple nervous system (eyespots) and octopi well developed brains and intelligent Excretory: nephridia remove ammonia Reproductive: sexually/internal or external fertilization Respiratory: Gills (aquatic) and Mantle cavity (terrestrial) Movement: muscular foot that it uses for movement or propulsion by pressing water from their pallial cavity, squids move backwards through the water like a rocket

Complex Invertebrates Phylum Annelida, Arthropoda & Phylum Echinodermata

Annelida • • Segmented worms Bilateral symmetry Tube shaped bodies Has a true coelom Ex: earthworms & leeches Complete digestive system No respiratory system (oxygen diffuses thru skin) Nervous system – pair of ganglia and a ventral nerve cord • Circulatory system – 5 aortic arches that serve as the heart and a dorsal & ventral blood vessel (closed) • Excretory system • Sexually reproduces – hermaphrodites – external fertilization

Annelida Chart • • • Germ layers: 3 Symmetry: Bilateral Cephalization Present True Coelom Circulatory: Closed/Dorsal and Ventral Blood Vessel Digestive/ Feeding: 2 openings- complete order: mouth, pharynx, esophagus, crop, gizzard, intestine and anus Nervous: well developed, brain and several nerve cords, 2 or more sets of eyes, sensory tentacles, statocysts Excretory: nephridia Reproductive: sexually/individual sexes/external fertilization/ clitellum Respiratory: Gills (aquatic) and Diffusion across skin (terrestrial) Movement: various muscle groups and simple appendages. They use setae and parapodia for movement

Arthropods • • Arthro = joint; Pod = foot All appendages are jointed Largest phylum in the animal kingdom Usually has 3 body sections: – Head – Thorax – Abdomen

Arthropoda Chart • • • Germ layers: 3 Symmetry: Bilateral Cephalization Present True Coelom Circulatory: Open System Digestive/ Feeding: herbivore, carnivore and omnivore/mouthparts vary Nervous: well developed, brain and sense organs: eyes, taste receptors Excretory: Malpighian Tubules/ Diffusion in aquatic arthropods Reproductive: sexually/individual sexes/internal (terrestrial) and internal or external (aquatic) Respiratory: Tracheal Tubes- Grasshoppers and Book Lungs- Spiders Movement: Jointed Appendages

Major Characteristics (continued) • Has an exoskeleton made of chitin which is shed when the arthropod grows – process is called MOLTING • Has a coelom – gut that holds all the organs • Have ALL the body systems • 5 classes – Arachnids – Centipedes – Millipedes – Crustaceans – Insects

Class Insecta • • • Able to fly Have antennae Compound eyes (multiple lenses) Open circulatory system Blood does not carry oxygen = blood is clear • Respiratory system = spiracles & book lungs • Goes through Metamorphosis = change in the body from the young to adult; triggered by hormones

Metamorphosis • Complete = 4 stages: Egg, Larva, Pupa, Adult • Incomplete = 3 stages: Egg, Nymph, Adult • Why go through this life cycle? ! – Adults and young have different homes, food sources and predators, therefore, they will not compete increasing their chance of survival

Echinoderms • Echino = spiny; derm = skin • Embryos develop like the embryo of vertebrates = DEUTEROSTOMES • Internal skeleton (endoskeleton) made of calcium plates • Water vascular system with tube feet that carry out its body functions

Echinodermata Chart • • • Germ layers: 3 Symmetry: Radial No Cephalization Deuterostome- Only Invertebrate Circulatory: Water Vascular System Digestive/ Feeding: carnivores tube feet Nervous: no head/not well-developed/ nerve rings and radial nerves Excretory: Feces released through anus and ammonia through tube feet or skin gills Reproductive: sexually/individual sexes/external Respiratory: Tube feet/ water vascular system and skin gills Movement: The water vascular system of echinoderms is responsible for their movement and ability to clean to surfaces for long periods of time