Table of Contents Chapter Preview 11.1 What is an Animal? 11.2 Sponges and Cnidarians 11.3 Worms and Mollusks 11.4 Arthropods 11.5 Echinoderms 11.1 What is an Animal? 11.2 Sponges and Cnidarians 11.3 Worms and Mollusks 11.4 Arthropods 11.5 Echinoderms

Chapter 11 Preview Questions 1. Which of the following animals appeared first during Earth’s history? a. fishes b. mammals c. worms d. reptiles

Chapter 11 Preview Questions 1. Which of the following animals appeared first during Earth’s history? a. fishes b. mammals c. worms d. reptiles

Chapter 11 Preview Questions 2. Which of the following structures is NOT found in animal cells? a. cell wall b. cell membrane c. mitochondria d. nucleus

Chapter 11Preview Questions 2. Which of the following structures is NOT found in animal cells? a. cell wall b. cell membrane c. mitochondria d. nucleus

Chapter 11 Preview Questions 3. If an animal reproduces asexually, it a. has two parent organisms. b. undergoes conjugation. c. is genetically identical to its offspring. d. inherits two different sets of alleles.

Chapter 11 Preview Questions 3. If an animal reproduces asexually, it a. has two parent organisms. b. undergoes conjugation. c. is genetically identical to its offspring. d. inherits two different sets of alleles.

Chapter 11 Preview Questions 4. If an animal has specialized tissues and organs, the animal’s cells have undergone a. photosynthesis. b. osmosis. c. selective breeding. d. differentiation.

Chapter 11 Preview Questions 4. If an animal has specialized tissues and organs, the animal’s cells have undergone a. photosynthesis. b. osmosis. c. selective breeding. d. differentiation.

Use Clues to Determine Meaning The animals called cnidarians have two different body plans. One form looks something like a vase. The vase-shaped body plan is called a polyp. A polypís mouth opens at the top and its tentacles spread out from around the mouth. What a polyp is Additional information about a polyp

Apply It! 1. In your own words, what is the meaning of polyp? Sample: A polyp is a vase-shaped cnidarian. 2. What sentence contains the definition of polyp? Sentence 3 3. What other clues help you understand the meaning of polyp? The last sentence tells me it has a mouth that opens at the top and is surrounded by spreading tentacles.

Section 11.1: What is an Animal? How are animal bodies typically organized? What are the four major functions of animals? What is symmetry? How are animals classified?

Structure of Animals The cells of most animals are organized into higher levels of structure, including tissues, organs, and systems.

Structure of Animals The cells of most animals are organized into higher levels of structure, including tissues, organs, and systems.

Classification of Animals This branching tree shows how the major animal groups are related.

Section 11.2: Sponges and Cnidarians? What are the main characteristics of sponges? What are the main characteristics of cnidarians?

Sponges Structures surrounding the central cavity of a sponge are adapted for different functions.

Cnidarians Cnidarians have two basic body plans, the vase-shaped polyp and the bowl-shaped medusa.

Cnidarians Cnidarians use stinging cells to capture food and defend themselves.

Cnidarians The life cycle of a moon jelly has both a polyp and a medusa stage, and both sexual and asexual reproduction.

Section 11.3: Worms and Mollusks What are the main characteristics of worms? What are the main characteristics of each phylum of worms? What are the main characteristics of mollusks? What are eth main groups of mollusks?

Characteristics of Mollusks Although they don’t look much alike at first, a snail, a clam, and a squid have the same basic body structures.

Characteristics of Mollusks Soft bodies Most with a hard shell Phylum Molluska   Characteristics of Mollusks Soft bodies Most with a hard shell Mantle to secrete shell and protect organs 3 Major Groups of Mollusks Gastropods: snails and slugs Bivalves: clams, oysters, scallops, and mussels 3. Cephalopods: Octopuses, cuttlefish, squid, and nautiluses

Gastropods 1. Gastropods: snails and slugs A single shell or no shell “Stomach foot”

Snails and Slugs Gastropods such as this land snail have an organ called a radula, which tears and scrapes up food.

Bivalves 2. Bivalves: clams, oysters, scallops, and mussels Two shells Filter feeders

Cephalopods Cephalopods: Octopuses, cuttlefish, squid, and nautiluses Swim by jet propulsion Complex nervous system Muscular tentacles with suckers

Characteristics of Worms Biologists classify worms into three major phyla—flatworms, roundworms, and segmented worms.

Life Cycle of a Dog Tapeworm This tapeworm is a parasite that lives in more that one host during its life cycle.

Segmented Worms Earthworms and other segmented worms have bodies made up of many linked sections called segments.

Section 11.4: Arthropods What are the general characteristics of arthropods? What are the distinguishing structures of crustaceans, arachnids, centipedes and millipedes, and insects?

Characteristics of Arthropods Invertebrates Exoskeleton Arthropods Ch 11.4   Characteristics of Arthropods Invertebrates Exoskeleton Segmented bodies “Jointed bodies” Open circulatory system Major Groups of Arthropods 1. Crustaceans  2. Arachnids:   3. Centipedes and millipedes

Crustaceans Crustaceans: crabs, barnacles, shrimp, crayfish   Crustaceans: crabs, barnacles, shrimp, crayfish Two or three body sections 3 pair of appendages for chewing 5 or more pair of legs

Crustaceans A crustacean is an arthropod that has two or three body sections, five or more pairs of legs, and two pairs of antennae.

Arachnids Arachnids: spiders, ticks, mites, and scorpions Two body sections 8 pair of legs no antennae

Insects Phylum Arthropoda Characteristics of Insects Invertebrates Exoskeleton Three body sections (head, thorax, abdomen) One or two pair of wings Open circulatory system Six legs Communication Sound Pheromones (perfume for insects)

Body Structure Insects are arthropods with three body sections, six legs, one pair of antennae, and usually one or two pairs of wings.

Life Cycle An insect with complete metamorphosis has four different stages: egg, larva, pupa, and adult.

Life Cycle An insect with gradual metamorphosis has no distinct larval stage. An egg hatches into a stage called a nymph, which usually looks like the adult insect without wings.

Defense in Insects Flying Camouflage Exoskeleton Smell or taste Stingers

Centipedes and millipedes Segmented bodies Appendages on each segment Centipedes are carnivores

Section 11.5: Echinoderms What are the main characteristics of echinoderms? What are the major groups of echinoderms?

Phylum Echinodermata Characteristics of Echinoderms Radial symmetry    Characteristics of Echinoderms Radial symmetry Ocean dwellers “spiney skinned” Endoskeleton of calcium plates Water vascular system Tube feet  

Characteristics of Echinoderms Echinoderms, such as this sea star, have a water vascular system that helps them move and catch food.

Diversity of Echinoderms There are four major groups of echinoderms: sea stars, brittle stars, sea urchins, and sea cucumbers. All have radial symmetry and are found in the ocean.