Chapter 28 and 29 Review Sheet

Describe the characteristics that separate the animal phyla from other phyla of living organisms.

**have nervous tissue and muscle fibers MOST animals have an advanced body plan that includes a central cavity (coelom), they make an extensive extracellular matrix to connect are multicellular, eukaryotic, and heterotrophic by ingestion

Discuss the evolution of vertebrates.

Chordates (including vertebrates) appeared at the start of the Cambrian period.The earliest vertebrates were fishes; most of which have jaws. Fish also had a bony skeleton, lungs, and fleshy fins, which were preadaptive for a land existence. Amphibians are the first vertebrates to live on land and to have four limbs (tetrapods). Amphibians are not fully adapted to living on land because they still have to reproduce in an aquatic environment. Reptiles are fully adapted to living on land because they produce an amniotic egg. Amniotes develop within an aquatic environment but of their own making. In placental mammals, the fertilized egg develops inside the female, where it is surrounded by an amniotic membrane. Another feature for living on land includes watertight skin, and can be seen in reptiles and mammals.

Give examples of the major groups of arthropods and describe their specializations.

Crustaceans: have 10 legs (3-5 pairs) and 2 pairs of antennae, crabs, shrimp, and lobsters, head/thorax fuse into cephalothorax, have gills Insects (Uniramians): have 6 jointed legs (3 pairs) can have/not have wings, and have 3 distinct body regions (head, thorax and abdomen), two antennae, Millipedes (2 pairs per segment) and Centipedes (1 pair per segment), appendages attached to the thorax, live on land (tracheae) Spiders/Scorpions/Ticks/Mites/Horshoe Crabs (Chelicerates): have 8 legs (4 pairs), no antenna, and a cephalothorax (head and thorax are fused), appendages attached to cephalothorax, 1st pair are feeding organs and 2nd pair are for feeding/sensory

List the characteristics of members of phylum Platyhelminthes.

Flatworms (free-living Planarians) and (parasitic Tapeworms and Flukes), have bilateral symmetry, 3 layers of tissue, are acoelomate (no body cavity)

Distinguish between the free-living flatworms and the parasitic flatworms.

Free-living flatworms (Planarians) feed on small, living or dead organisms; body wall ciliated epidermis, head with eyespots and auricles, nerves and brain, have a more developed branched digestive system, hermaphroditic Parasitic flatworms (Tapeworms) live in the intestines of animals; Parasitic flatworms (Flukes) live in their hosts' blood, liver, or lungs: body wall specialized for absorption, specialized have a way to attach themselves to their host and acquire nutrients through oral suckers or a scolex with hooks and suckers, nervous system reduced, digestive system reduced, reproductive system expanded and extensively developed

List and describe examples of the major groups within phylum Mollusca.

Gastropods: (Snails and Slugs) has a large foot beneath the visceral mass Bivalves: (Oysters and Clams) have a left and right shell (exoskeleton), filter feeders, have no cephalization (no head) burrow in sand by muscular foot, open circulatory system Cephalopods (Octopus and Squids) closed circulatory system, well defined head that contains a brain and sense organs, predator, has tentacles, moves by jet propulsion of water, has beak like jaws and a radula (beltlike rows of teeth)

List examples of cnidarians.

Jellyfish, corals, sea anemones, hydra

Explain the data used to develop the animal phylogenetic tree.

Level of organization (cell, tissue, organ, organ system) Body Plan (sac plan vs. tube-within-a-tube plan) Symmetry (asymmetry, radial symmetry, and bilateral symmetry) Tissue layers (ectoderm, mesoderm, and endoderm) 2 or 3 germ layers Type of Coelom (acoelomate, pseudocoelom, coelom) Protostome or Deuterostome

List and describe examples of roundworms and their effects on humans.

Pinworms and Hookworms cause intestinal difficulties Trichinella causes Trichinosis by eating raw/undercooked pork with trichinella cysts, juvenile worms go into digestive tract and then will penetrate wall of small intestine to sexually mature Filarial worm causes elephantiasis infects lymphatic vessels and blocks flow of lymph, which can cause swelling in appendages

Distinguish between the major groups of annelids.

Polychaetes (have many bristles or setae) Clam Worm and Fanworm Oligochaetes (have fewer setae or bristles) Earthworms are hermaphroditic, feed on decaying organic matter in soil, have a clitellum (makes mucus for holding worms together during mating) Leeches (have no setae or bristles) are bloodsuckers

Describe the sponges.

Porifera, are multicellular, heterotrophs by ingestion, no tissues, no symmetry collar cells (choanocyte) have a flagella to produce water currents, filter feeders, asexual reproduction (fragmentation/budding), saclike porous bodies

List examples of the major groups of echinoderms.

Sea Star, Sea Urchins, Sea Cucumbers, name means "spiny skinned"

Discuss the "colonial flagellate hypothesis" as it relates to the evolution of animals.

The colonial flagellate hypothesis states that animals are descended from an ancestor that resembled a hollow spherical colony of flagellated cells. The colonial flagellate hypothesis implies that radial symmetry preceded bilateral symmetry in the history of animals. The choanoflagellates (collared flagellates) most likely resemble the last unicellular ancestor of living animals, and molecular data illustrates that they are the closest living relatives of animals. A choanoflagellate is a single cell, 3-10 μm in diameter, with a flagellum surrounded by a collar of 30-40 microvilli. As the water moves through the microvilli, they engulf bacteria and debris from the water.

Discuss the adaptations of sea stars and how they relate to the characteristics of echinoderms in general.

have 5 arms that radiate from a central disk; mouth faces down; use tube feet (suction) to force the clam shells open, evert cardiac portion of stomach which releases digestive juices into the mantle cavity of the clam, partially digested tissues are taken up by the pyloric portion of the stomach

Discuss the characteristics of mollusks.

have bilateral symmetry, 3 tissue layers, coelomate (real body cavity), protostome, open circulatory systems (no closed vessels) where heart pumps lymph (clear fluid), have a 3 part body plan Muscular Foot (locomotion), Visceral Mass (internal organs), and a Mantle (encloses the visceral mass and may secrete a shell), complete/closed digestive tract

Discuss the five characteristics credited for the success of arthropods.

have bilateral symmetry, 3 tissue layers, coelomate (real body cavity), protostome, have jointed appendages, hard exoskeleton (chitin), can molt, metamorphosis

Describe the characteristics of echinoderms.

have bilateral symmetry, 3 tissue layers, coelomates, deuterostome, have adult radial symmetry but larvae are bilateral have a water vascular system and use tube feet for locomotion, gas exchange, or food gathering; their defensive spines come from an exoskeleton made of calcium carbonate, it supports body wall and covered by hard living tissues (sea urchins) or soft living tissues (sea cucumbers)

Describe roundworms (phylum Nematoda)

have bilateral symmetry, 3 tissue layers, pseudocoelomate (false body cavity)

Describe rotifers.

have bilateral symmetry, 3 tissue layers, pseudocoelomate (false body cavity) has a complete digestive tract (mouth and anus), filter feeders (corona-crown of cilia around the mouth that draws water into the mouth)

Describe and give examples of the two non-vertebrate chordates.

have bilateral symmetry, have 3 tissue layers, are coelomates, deuterostomes, have a notocord but never develop a vertebral column Lancelots: straight and rigid Sea Squirts: had all 4 characteristics during their larva stage, as an adult they lose all except the notochord, as adults they look like a blob, filter feeders

Discuss the specializations unique to cnidarians.

have radial symmetry, 2 tissue/germ layers (ectoderm & endoderm) have 2 basic body forms (polyp-mouth up) and the (medusa-mouth down), have specialized stinging cells called cnidocytes, each cnidocyte has a fluid-filled capsule called a nematocyst, which has a long, spirally coiled hollow thread which trap/sting prey, nerve net found throughout body

Describe the four features in addition to the chordate characteristics which characterize the vertebrates.

living endoskeleton with vertebral column (vetebrae replace notochord), closed circulatory system, paired appendages, efficient respiration/excretion, cephalization, active lifestyle

Outline the four characteristics of chordates.

notochord, nerve chord, pharyngeal pouches, tail have bilateral symmetry, have 3 tissue layers, are coelomates, deuterostomes

Distinguish between protostomes and deuterostomes.

protostomes (first embryonic opening becomes the mouth); deuterostomes (second opening becomes the mouth)

Describe the major characteristics of annelids.

segmented worms, have bilateral symmetry, 3 tissue layers, coelomate (real body cavity), protostome closed circulatory system, setae (bristles) help with movement

List the seven derived characteristics used to form the chordate phylogenetic tree.

vertebrae, jaws, bony skeleton, lungs, 4 limbs, amniotic egg, mammary gland