BIO Ch.30-31 PDF

Ch 30- The Animal Kingdom “An Intro” Describe what an animal is: 1) Multicellular eukaryotes 2) Cells are organized into complex tissues 3) Heterotrophic 4) Capable of locomotion- sessile 5) Can respond to a stimuli- nervous system and muscles...

Ch 30- The Animal Kingdom “An Intro” Describe what an animal is: 1) Multicellular eukaryotes 2) Cells are organized into complex tissues 3) Heterotrophic 4) Capable of locomotion- sessile 5) Can respond to a stimuli- nervous system and muscles 6) Reproduce Where do biologists think animals came from? Key words dealing with body plans- basic structures of the body 1) Radial symmetry- 2) Bilateral symmetry- 3) Asymmetry- 4) Dorsal- 5) Ventral- 6) Anterior- 7) Posterior- 8) Medial- 9) Sagittal plane- 10) Frontal plane- 11) Cross section-  Body Cavity and Germ layer Germ layers-embryonic tissue layers; three layers A. Ectoderm- outer germ layer; gives rise to the outer coverings and nervous system B. Endoderm- inner germ layer; gives rise to the lining of the digestive tube and digestive organs C. Mesoderm- Give rise to muscles, skeletal and circulatory systems Diploblastic- develop two germ layers; example- cnidarians; ectoderm and endoderm Triploblastic- develop all three germ layers; example- you! Grouping of Triploblastic organisms by body cavity style Coelom- fluid filled space between the body wall and digestive tube A. Acoelomates- without cavity; solid body plan (exp- flatworm) B. Pseudocoelomates- body cavity is not completely lined with mesoderm (exp- round worm) C. Coelomate- A “true” body cavity is completely lined with mesoderm (exp- you) Development of Coelomates cleavage- means dividing A. Protostomes- means first mouth; determinate cleavage; Spiral cleavage (exp- Mollusca, Annelida, and Arthropods) - Determinate = fixed B. Deuterostomes- Second mouth; cleavage is indeterminate; Radial Cleavage (Exp- Echinoderms and Chorates) Pop quiz is only on Ch.30 2  Ch 31- Protostomes Animal groups without a coelom 1) Phylum Porifera- means “to have pores” a. Evolved from choanoflagellates; Single flagellum surrounded by a collar of microvilli called Choanocytes or collar cells b. Larve are flagellated and able to swim but adults are sessile c. Suspension feeders d. Asexual or sexual reproduction e. Hermaphroditic- produce sperm and egg/have male and female parts (ex: flatworms) f. Cell are loosely arranged- not tri or diploblastic g. Skeleton made of spicules h. Feed on simple diffusion- no mouth or anus 2) Phylum Cnidaria- a. Marine b. Contain stinging cells (nematocysts - found in epidermis) c. Have radial symmetry d. Body plan- hollow sac with mouth and tentacles located at one end; only one opening serving as mouth and anus e. for circulation and gas exchange they depend on diffusion f. Diploblastic (2 tissue layers) Two body shapes A) Polyp- hydra form; mouth dorsal (up) B) Medusa- jellyfish form; mouth ventral (down) 3 classes A. Hydrozoa- hydra; medusa and polyp stage 3  B. Scyphozoa- jelly fish; medusa stage is dominate stage C. Anthozoa- Sea anemones and corals; no medusa stage, all hydra; coral reefs hydrostatic skeleton- water used to support the body and allow for movement 3) Phylum Platyhelminthes- exp- flatworms; their body plan makes them fall into the category of acoelmates; they have bilateral symmetry; they have a small brain made of ganglia; eyespots; some members are parasitic; respiration occurs right through the cells known as diffusion protonephridria- kidney like organ Three classes a) Class Turbellaria- exp- planaria; marine; free living; eye spots and auricles that serve for chemoreception; they are carnivorous; it digests animals by ejecting its pharynx and secreting enzymes; flat in shape for diffusion; produce sexually or asexually; the term for having male and female parts is hermaphroditic b) Class Trematoda- exp- fluke; all are parasites; adults have suckers; infect humans that live in poverty conditions Host- the organism that the parasite robs from c) Class Cestoda- exp- Tapeworm; the head region is called the scolex and has many hooks for attachment; each chain of a tape worm is called a proglottid and has male and female parts; they produce millions of eggs per year 4) Phylum Mollusca- clams, oysters, octopods, snails, slugs, and squid 4  Body Plan of Mollusca A) Soft body, usually covered by calcium carbonate B) A foot- a flat muscle, used for locomotion C) Body organs form a visceral mass above the foot D) Has a mantle- covers the visceral mass and secretes a shell E) Radula- rasplike structure in mouth region F) Body cavity is a hemocoel- a space containing blood G) Most have Open circulatory system- blood bathes tissues directly; slow moving; low metabolisms H) Cephalopods (squid) have Closed circulatory systems- Circuit of blood vessels 4 classes of Mollusca 1) Polyplacophora- slug-like marine animals; eight overlapping plates; found in intertidal zones; very muscular foot; open circulatory system 2) Gastropoda- 2nd largest only to insects; torsion- twisting of the visceral mass; allows the head to be the first part to retract into the head; unrelated to the shell; open circulatory system 3) Bivalvia- 2-part shell that is hinged; each part is called a valve; some species are suspension feeders; incurrent siphon and excurrent siphon; no radula; young grow in the gills of female; open circulatory system 4) Cephalopoda- fast-swimming predatory animals; has a funnel like siphon; defense ink sac and chromatophores; shell-less mollusk; small shell located inside the body; closed circulatory system 5 Pop quiz on phylum Mollusca 5) Phylum Annelida- segmented worms- each segment has its own muscle and coelom for movement; bilateral symmetry; tubular body; setae hairs (worm hair)on each segment; closed circulatory system Three Classes of Annelida 1) Polychaeta- all marine; each segment has a paddle-shaped appendage called parapodia for locomotion and gas exchange; parapoda have setae (hair) 2) Oligochaeta- (exp-earthworms) lack parapodia; few seta; hermaphroditic; the clitellum allows transfer of sperm 3) Hirudinea-leeches; blood sucking parasites; muscular suckers; secretes anticoagulant called hirudin; don’t have setae or parapoda 6) Phylum Nematoda- roundworms; many are parasites; threadlike body 3 Roundworm life cycles 1) Ascaris- separate sexes; eggs leave in feces; humans become infected by eating with dirty hands or unwashed fruits and vegetables; hatch in the intestines 2) Hookworm- lay eggs in intestines; passed by feces; larvae hatch and feed on bacteria; larvae enter the body by bare feet through the skin; they migrate to intestines 3) Pinworms- found in children; adult worms deposit eggs in anal region 6 7) Phylum Arthropoda- means jointed appendages a. Segmentation- separate compartments of the body; allow for specialized functions b. Exoskeleton- composed of chitin; protects from predators and moisture loss and gives support; to increase in size the organism must molt- shedding of exoskeleton, a metabolic loss and leaves the animal vulnerable to predators. c. Paired, jointed appendages- modified for many different functions Claws, swimming, flying d. Many sense organs- antennae for taste and touch compound eyes- with many lenses called ommatidia e. complete digestive tract 3 subphylum of Arthropoda 1) Subphylum Chelicerata- horseshoe crabs, spiders, scorpions, ticks, and mites a) no antennae b) first appendage are fanglike feeding appendages called chelicerae c) the body plan is composed of a cephalothorax (fused head and thorax) and abdomen classes- A. Merostomata- (exp: horseshoe crabs); tail used for locomotions B. Arachnids- (exp:spiders, scorpions, ticks and mites); spiders have a silk gland that allows the spider to make a dragline; the dragline serves as a safety line and for communication between members of the same species. 7 2) Subphylum Crustacean- a) Two pairs of antenna (used for touch and taste) b) biramous appendages c) mandibles- used for biting and grinding food; in the oral cavity d) have statocyst used to detect gravity e) Barnacles are the only sessile crustacean f) body plan- cephalothorax (fused head and thorax) and abdomen 3) Subphylum Hexapoda- insects a) single pair of antennae b) uniramous appendages c) the most successful group of animals in every aspect- wings! d) body plan- head, thorax, abdomen Metamorphosis (reduces intraspecific competition) types: a) Incomplete metamorphosis- larva resemble adults but lack wings and reproductive structures (ex: cockroaches) b) Complete metamorphosis- four different stages (ex: monarch butterfly) Egg → larva → pupa → Adult Larva- looks nothing like the adult; most of the lifespan is spent in this stage (caterpillar-like stage) Pupa- “The changing stage;” no feeding; cannot defend itself (organisms will hide during this stage so they’re not eaten) Adult- functional wings The End 8 9