Campbell Biology Chapter 33
Animals without a backbone. About 95% of known animal species.
Calcarea and Silicea
phylum that includes sponges; no symmetry, tissues, body cavity, organs, nervous system; basal animals; mostly marine; contain spicules; most are hermaphrodites; free-swimming during larval stage and sessile (non motile) as adults; suspension/filter feeders
small and large organisms that use filtering and trapping techniques to collect minute food particles suspended in the water
large central cavity of the sponge
A large opening on a sponge through which filtered water is expelled
specialized cell in sponges that uses a flagellum to move a steady current of water through the sponge
a gelatinous region between the two layers of cells of a sponge
the "do-all" cells of sponges, moving by means of pseudopodia, they digest and distribute food, transport oxygen, and disposes of waste. they manufacture the fibers that make up a sponges skeleton
Members of the subkingdom that includes all animals except sponges. (true tissues)
animal phylum characterized by having diploblastic tentacled polyp and/or medusa (jelly) body forms with radial symmetry; tentacles bear cells called cnidocytes that have weapons called cnidae (e.g., stinging barbs called nematocysts). Gastrovascular cavity with a single opening. - corals, jellies and hydras
digestive chamber with a single opening, in which cnidarians, flatworms, and echinoderms digest food
The sessile variant of the cnidarian body plan. The alternate form is the medusa. Cylindrical forms that adhere to the substrate by the aboral end of their body, waiting for the prey. - hydras
The floating, flattened, mouth-down version of the cnidarian body plan. The alternate form is the polyp.
a specialized cell for which the phylum Cnidaria is named; consists of a capsule containing a fine coiled thread, which, when discharged, functions in defense and prey capture
a type of cnidocyte that has a long filament coiled up inside it and can penetrate the prey.
4 major classes of phylum Cnidaria
Hydrozoa, Scyphozoa, Cubozoa, Anthozoa
A class of Cnidaria where most of the organisms alternate between polyp and medusa except hydras, which are only polyp. They can reproduce both asexually and sexually.
Group of cnidarians,all marine, polyp stage is greatly reduced, free swimming medusae is up to 2 m in diameter. (Jellies,sea nettles)
Class of Cnidaria with a box-shaped medusa stage and complex eyes. Often equipped with toxic cnidocytes.
class of cnidarian; sea anemones and corals occurring only as polyps. Corals excrete an exoskeleton of calcium carbonate, form symbioses with algae.
Member of a group of animal phyla identified as a clade by molecular evidence. Lophotrochozoans include organisms that have lophophores or trochophore larvae. Includes about 18 phyla - introduced 6 are flatworms, rotifers, ectoprocts, brachiopods, molluscs and annelids.
A member of a major lineage of animals (Bilateria) that are bilaterally symmetrical at some point in their life cycle, have three embryonic germ layers, and have digestive tract with two opening and a coelom. All protostomes and deuterostomes are bilaterians.
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3 major clades of Bilateria
In some lophotrochozoan animals, including brachiopods, a crown of ciliated tentacles that surround the mouth and function in feeding.
Distinctive larval stage observed in some lophotrochozoan animals, including some annelids and molluscs.
Phylum Platyhelminthes (flatworms)
Distinct organ systems, Bilateral Symmetry, Acoelomate, Three tissue levels, Cephalization, Gastrovascular cavity—only one opening-acts as the mouth and the anus, Tubular mouth (pharynx) at mid-body, Primitive nerve cords, Protonephridia work similar to kidneys, Sexual (some are hermaphroditic) and some Asexual Reproduction (body split), Most members are parasitic (tapeworms, liver flukes), Some are free living (Planaria), Protostomes
networks of tubules with ciliated structures called flame bulbs that pull fluid through branched ducts opening to the outside. Regulates the osmotic balance.
live in freshwater. Most are predators. They digest food in a gut. They find food using their sensory lobes. They have light-sensitive eyespots and centralized nerve nets. Have a well-developed nervous system. Are hermaphrodites and can reproduce sexually or asexually through fission.
Reproductive organs occupy nearly the entire interior. 2 important groups - Trematodes and Tapeworms.
Parasites (such as blood flukes) have complex, alternating life cycles. Usually they have to infect a preliminary host where larvae grow before infecting the final host. Human parasites spend part of their lives in snail hosts.
Parasites that infect vertebrates including humans. Most have a hook called a scolex that helps them stick to the intestines of the host. They have sacs of eggs called proglottids that lay eggs into feces, which can contaminate meat.
Tiny filter feeders. Pseudocoelomates with complex, complete digestive systems.
digestive tube with two openings in rotifers
Asexual reproduction in which females produce offspring from unfertilized eggs.
lophotrochozoan; sessile colonies, covered by tough exoskeleton - sea mat. Colonial animals, important reef builders. Common name "moss animals"
the exterior protective or supporting structure or shell of many animals (especially invertebrates) including bony or horny parts such as nails or scales or hoofs
resemble clams, two halves of the shell are dorsal and ventral not lateral as in clams, marine and attach to the seafloor by a stalk
Motile organisms with soft bodies and hard shells. Are the first protostomes and the first coelomates (with spiral, determinate cleavage). Include gastropods, bivalves, cephalopods. E.g. octopuses, squids, snails, clams.
part of a mollusks head-foot whose function is locomotion
One of the three main parts of a mollusk, it contains most of the internal organs
a protective layer of epidermis in mollusks or brachiopods that secretes a substance forming the shell
A water-filled chamber that houses the gills, anus, and excretory pores of a mollusc.
a straplike rasping organ used by many mollusks during feeding
Four major classes of molluscs
Polyplacophora (chitons), Gastropoda (snails and slugs), Bivalvia (clams, oysters, Cephalopoda (squid, octopuses, cuttlefish and chambered nautiluses.))
Molluscs with an oval shaped body and 8 dorsal segmented plates of shells. Their foot functions as a suction cup to rocks and also for movement, and they use their radula to eat algae.
Form 3/4 of all molluscs. They had a developmental process called torsion, where the visceral mass rotates, so the anus and mantle cavity are above its head. Many have shells and distinct eyes, and travel using their feet. Some of predators and some are grazers.
In gastropods, a developmental process in which the visceral mass rotates up to 180°, causing the animal's anus and mantle cavity to be positioned above its head.
mollusks that have two shells held together by hinges and strong muscles - clams, oysters
octupuses, squids, nautiluses, and cuttlefish, ocean-dwelling mollusks whose foot is adapted to form tentacles around its mouth. Squids use their siphon to fire a jet of water, which allows them to swim very quickly. They have a closed circulatory system, well-developed sense organs and a complex brain.
shelled chephalopods that were the dominant invertebrae predators a long time ago
(segmented worms) tube shaped bodies divided into sections; are eucoelomates, a body cavity with organs inside;simplest animals with a circulatory system; have specialized organs for digestion; divided into 2 groups - polychaeta (polychaetes), oligochaeta (earthworms, leeches).
A class of annelids that have parapodia, ridgelike structures that help it move. The parapodia have numerous chaetae and can also function as gills.
This class of annelids have sparse chitin bristles called chaetae, including earthworms. Earthworms till the soil and their secreted waste improves the soil texture. They are hermaphrodies that cross-fertilize.
A class of annelids. Some are predators and some are parasites that suck blood. It secretes anesthesia and hirudin, which prevents blood clotting, to help it suck blood.
A major lineage of protostomes (Ecdysozoam) that grow by shedding their external skeletons (molting) and expanding their bodies. Includes arthropods, insects, crustaceans, nematodes, and centipedes.
hard outer covering or case of certain organisms such as arthropods and turtles
roundworms found in aquatic habitats, in the soilk, moist tissues of plants, body fluids, animal tissue. They have an alimentary canal, but lack a circulatory system. Sexual reproduction by internal fertilization.
Used as model for animal development, partly because it has mosaic development and the lineage of all adult cells are known. Nematoda
parasitic nematode occurring in the intestines of pigs and rats and human beings and producing larvae that form cysts in skeletal muscles
The largest phylum includes invertebrates with jointed appendges, a segemented bilateral body, and in most species an exoskeleton.
In invertebrates with an open circulatory system, the body fluid that bathes tissues.
4 major lineages of arthropods
chelicerates, myriapods, hexapods, crustaceans
(Chelicerata) A major group of arthropods with pointed appendages (chelicerae) used to grasp food (as opposed to the chewing mandibles of most other arthropods). Includes the arachnids, horseshoe crabs, pycnogonids, and extinct sea scorpions.
A member of a major arthropod group that includes spiders, scorpions, ticks, and mites. All members have eight pairs of walking legs.
Organs of gas exchange in spiders, consisting of stacked plates contained in an internal chamber.
A terrestrial arthropod with many body segments and one or two pairs of legs per segment. millipedes and centipedes comprise the two classes of living myriapods. centipeds are cornivores and hav 1 pair of legs per trunk segment.
"Insects and relatives. flight is one key to success of insects: can escape predators, find food, and disperse to new habitats. Many insects undergo metamorphosis. Incomplete metamorphosis: young are called nymphs, and resemble adults but are smaller and molt until reach full size. Complete metamorphosis: Many larval stages. Most insects reproduce sexually; some are pollinators; some carry diseases or are pests. "
A type of development in certain insects, such as grasshoppers, in which the young (called nymphs) resemble adults but are smaller and have different body proportions. The nymph goes through a series of molts, each time looking more like an adult, until it reaches full size.
A developmental process where the larva are specialized for eating and growing and look nothing like the adult. Larval stages are maggot, grub, caterpillar. They transition through a pupal stage to reach adulthood.
Any of various predominantly aquatic arthropods of the class Crustacea, including lobsters, crabs, shrimps, and barnacles, characteristically having a segmented body, a chitinous exoskeleton, and paired, jointed limbs.
A member of one of the largest groups of crustaceans, which includes terrestrial, freshwater, and marine species. Among the terrestrial isopods are the pill bugs, or wood lice.
Group of crustaceans that includes crabs and lobsters. The cuticle is reinforced, forming a dorsal shield called the carapce.
planktonic crustaceans, they are the most numerous of all animals
A member of a group of slow moving or sessile marine animals characterized by a rough or spiny skin, a water vascular system, an endoskeleton, and a radial symmetry in adults, with examples such as sea stars, sea urchins and sand dollars
One of two distinct evolutionary lines of coelomates, consisting of the echinoderms and chordates and characterized by radial, indeterminate cleavage, enterocoelous formation of the coelom, and development of the anus from the blastopore
water vascular system
A network of hydraulic canals unique to echinoderms that branches into extensions called tube feet, which function in locomotion, feeding, and gas exchange
5 classes of living echinoderms
"Asteroidea (sea stars and sea daisies), Ophiuroidea (brittle stars), Echinoidea (sea urchins and sand dollars), Crinoidea (sea lilies and feather stars), Holothuroidea (sea cucambers) "
Class of Echinodermata (starfish) carnivorous predators; slow movement; central disk with arms; secrete enzymes and digests prey
Ophiuroidea (brittle stars)
Characteristics of this class of echinoderm include: Arms that are distinct from central disk. Uses arms for locomotion and not tube feet. Unique photo-receptive organs. Some suspension eaters, some predators or scavengers.
Echinoidea (sea urchins and sand dollars)
these have no arms, but five rows of tube feet that function in slow movement
Crinoidea (sea lilies and feather stars)
Feathered arms surrounding upward-pointing mouth
Holothuroidea (sea cucambers)
lack spines, reduced exosceleton
an animal phylum in which all members have a notochord, dorsal nerve cord and pharyngeal gill slits at some embryonic stage; includes the Cephalochordata and the Vertebrates