EOCT REVIEW

Animals

PORIFERA• Asymmetrical

• Filter Feeder (collar cells, choanocytes, capture food with flagella)

• Amoebocytes are cells that digest and circulate nutrients

• Spicules made of CaCO3 or SiO2 give support

• Wastes diffuse through the cell membrane

Coral - polyp form

Jellyfish - medusa form

Hydra - polyp form

Sea Anemone - polyp form

Cnidaria• Radial symmetry• Tentacles have cnidocytes that sting

and paralyze prey. Shove food into mouth of gastrovascular cavity

• Both asexual and sexual• Digest and circulate food in

gastrovascular cavity.• Undigested food exits the mouth• Nerve net detects environment• Cellular waste diffuses through the

cell membrane

Flatworms• Bilateral symmetry• Muscular pharynx pumps food into

gastrovascular cavity• Hermaphroditic (both male & female)

& asexual by fission• Cephalization (concentration of sense

organs and nerve tissue at anterior end) Brain and Eyespots

• Digest and circulate nutrients in gastrovascular cavity

• Parasitic worms have a cuticle which prevents digestion by host.

• Flame cells remove metabolic wastes and excess water

Planarian

Tapeworm

Roundworms• Bilateral symmetry

• Most are free-living and eat small animals, or algae, or bacteria.

• Parasitic roundworms include trichinosis-causing worms, filarial, worms, ascarid worms, and hookworms.

• Cephalization, ganglia, sense organs that detect chemicals.

• First to have a complete digestive tract with mouth and an anus

• Depend on diffusion to carry nutients and wastes through their bodies.

• Hydrostatic skeleton (pseudocoelom)

• Reproduce sexually (have separate sexes). Internal fertilization

Mollusks • The body plan of most mollusks has four parts: foot, mantle, shell, and visceral mass. Bilateral symmetry.

• Can be herbivores, carnivores, filter feeders, detritivores, or parasites.

• Reproduce sexually by either internal or external fertilization. Some are hermaphroditic

• Clams have simple nervous systems. Can sense light and chemicals. Octopi and relatives have the most highly developed system of all invertebrates, intelligent predators.

• Complete digestive system

Mollusks Circulation

• Open circulatory system - blood is pumped by a simple heart into vessels which empty into sinuses, into gills, back into the heart. Works well for slow moving animals like clams and snails

• Faster moving mollusks (Octopi and relatives) have a closed circulatory system - blood remains in vessels. Transports blood faster.

Mollusk Support & Excretion

• Mantle covers most of the body and secretes shell. Shell is made of calcium carbonate.

• Bivalves have two shells

• Univalves have one shell

• Metabolic waste is in the form of ammonia.

• Nephridia remove ammonia from the blood and release it outside the body.

Annelids• Bilateral symmetry• Pharynx, filter feeders, or parasites.• Most reproduce sexually, separate sexes or

hermaphroditic. Earthworm clitellum secretes a mucus ring into which eggs and sperm are released.

• Most have well developed nervous system. Sense organs are best developed in the free-living marine worms (sensory tentacles, chemical receptors, statocysts, and 2 or more pairs of eyes)

• Gizzard grinds food which is chemically digested in the intestine.

• Closed circulatory system• Hydrostatic skeleton• Nephridia

Arthropods• Arthropods have a segmented body, a

tough exoskeleton, and jointed appendages. Bilateral Symmetry

• Herbivores, carnivores, and omnivores. Bloodsuckers, filter feeders, detritivores, & parasites.

• Terrestrial arthropods have internal fertilization. Aquatic arthropods have internal or external fertilization.

• Well devloped nervous system. Brain and ventral nerve cord. Well developed sense organs such as eyes and taste receptors.

Arthropods Systems• Complete digestive tract.• Open circulatory system

- blood does not carry oxygen

• Tracheal tubes carry oxygen. Air enters and leaves through spiracles.

• Spiders have book lungs. Horshoe crabs have book gills

• Aquatic arthropods have gills

• Exoskeleton made of chitin

• Malpighian tubules are saclike organs that extract wastes from the blood and then add them to feces that move through the gut.

• Aquatic arthropods wastes diffuse from cells into water.

Echinoderms• Radial symmetry. • Use tube feet to capture prey• Separate sexes. External Fertilization• Most have a nerve ring and radial nerves

with sensory cells that detect light, gravity, and chemicals. Poorly developed.

• Starfish pushes stomach out through its mouth, pours out enzymes, and starts digestion outside.

• Circulation and respiration through the water vascular system

• Endoskeleton made of calcium carbonate• Solid waste out the anus. Cellular wastes,

ammonia, through tube feet and skin gills

Chordates• A chordate is an animal that has, for at least some stage of its life, a dorsal, hollow nerve cord; a notochord; pharyngeal pouches; and a tail that extends beyond the anus.

• Two groups of nonvertebrate chordates are tunicates and lancelets.

• Tunicates are filter feeders. Adult tunicates lack a tail and notochord

• Lancelets are filter feeders• Eggs of nonvertebrate chordates are fertilized

externally.• Have a relatively simple nervous system with a

mass of nerve cells that form a brain• Simple closed circulatory system• Notochord (rod of cartilage) for support• Excretion through gills

Vertebrates• Baleen whales,

flamingoes, and manta rays are filter feeders

• Canines have sharp canines and incisors with short digestive tracts

• Herbivores have long digestive tracts with colonies of bacteria that help digest cellulose. Large molar teeth for grinding food.

• Some are omnivores

Reproduction• Fish and amphibians have exernal fertilization

• Reptiles, birds and mammals are fertilized internally

• Oviparous (most fishes, amphibians and all birds) eggs develop outside the mother’s body

• Ovoviviparous (some fishesand reptiles) eggs develop within the mother’s body and the embryos receive nutrients from the yolk in the egg. They are born alive.

• Viviparous (most mammals) obtain nutrients directly from the mother’s body. Young born alive

Detect Environment

• High degree of cephalization

• Head contains a well-developed brain attached to a spinal cord.

• The brain is divided into several parts, including the cerebrum (learning, memory, and conscious thought) , cerebellum(coordinates movement and controls balance), medulla oblongata (controls functioning of internal organs), optic lobes (vision) and olfactory bulbs in(sense of smell)

Digest & Circulate Nutrients• The digestive systems of vertebrates have organs

that are well adapted for different feeding habits.• Fishes have a single-loop circulatory sytem with a

two chambered heart.• Vertebrates that use lungs for respiration have a

double-loop circulatory system. The first loop carries blood between the heart and lungs. The second between the heart and the body.

• Amphibians and most reptiles have a three chambered heart.

• Birds and mammals have a four chambered heart.

Support & ProtectExcrete Waste

• Sharks have a skeleton made of cartilage.• Most vertebrates have a skeleton made of bone.• Excretion is carried out mostly by the kidneys• Aquatic amphibians and most fishes excrete ammonia

directly from the gills into water in addition to excreting through the kidneys.

• In mammals, land amphibians and cartilaginous fishes ammonia is changed into urea.

• In most reptiles and birds, ammonia is changed into uric acid.