Presentation on theme: "Interest Grabber What’s the Difference? In the course of the day, you probably have encountered animals and other types of organisms. Section 26-1 1.Make."— Presentation transcript:
Interest Grabber What’s the Difference? In the course of the day, you probably have encountered animals and other types of organisms. Section Make a list of five animals that you saw today. 2.Then, make a list of five organisms other than animals that you saw today. 3.What characteristics do animals have that the other types of organisms do not?
Section Outline 26–1Introduction to the Animal Kingdom A.What Is an Animal? B.What Animals Do to Survive 1.Feeding 2.Respiration 3.Circulation 4.Excretion 5.Response 6.Movement 7.Reproduction C.Trends in Animal Evolution 1.Cell Specialization and Levels of Organization 2.Early Development 3.Body Symmetry 4.Cephalization 5.Body Cavity Formation Section 26-1
havearecarry out withsuch as Concept Map Animals FeedingRespirationCirculationExcretionResponseMovementReproduction Eukaryotic cells Heterotrophs Essential functions No cell walls
Section 26-1 Radial Symmetry Bilateral Symmetry Planes of symmetry Plane of symmetry Ventral side Dorsal side Posterior end Anterior end Figure 26–5 Body Symmetry
Section 26-2 No Sinking or Swimming You likely have a green, yellow, blue, or pink sponge in your kitchen sink at home. This is a synthetic (human-made) sponge, not a natural sponge. But you may have used a natural sponge in the bath or when washing the car. These sponges are usually brownish and are irregularly shaped. Interest Grabber 1. Natural sponges live in the water, and are attached to a single spot. Although they cannot move from place to place like many other animals, sponges are still animals. Because they are animals, what characteristics must sponges have? 2. What characteristics does a kitchen sponge have? Which of these characteristics do you think a natural sponge has?
26–2Sponges A.What Is a Sponge? B.Form and Function in Sponges 1.Body Plan 2.Feeding 3.Respiration, Circulation, and Excretion 4.Response 5.Reproduction C.Ecology of Sponges Section 26-2 Section Outline
Section 26-2 Sperm from a sponge are released into the surrounding water. Water currents carry the sperm to other sponges. Sperm enter another sponge through pores. The sperm are carried to eggs inside the body wall. Sperm fertilize eggs. The zygote develops into a free-swimming larva. Water currents carry the larva until it attaches to a surface and grows into a new sponge. Sperm (N) Egg (N) Larva (2N) Mature sponge (2N) Swimming larva New sponge Haploid (N) Diploid (2N) FERTILIZATION MEIOSIS Sponge Life Cycle
Section 26-2 Water flow Choanocyte Spicule Pore cell Pore Epidermal cell Archaeocyte Osculum Central cavity Pores Figure 26–8 The Anatomy of a Sponge
Interest Grabber What’s in a Name? Perhaps you have heard about creatures called jellyfishes on television, in school, or at an aquarium; maybe you live near the ocean and have actually seen jellyfishes. Section Do jellyfishes look like what their name describes? Make a simple drawing of what you think a jellyfish looks like. 2.Some scientists suggest that jellyfishes should be called “jellies.” What might this new name tell you about jellyfishes?
26–3Cnidarians A.What Is a Cnidarian? B.Form and Function in Cnidarians 1.Body Plan 2.Feeding 3.Respiration, Circulation, and Excretion 4.Response 5.Movement 6.Reproduction C.Groups of Cnidarians 1.Jellyfishes 2.Hydras and Their Relatives 3.Sea Anemones and Corals D.Ecology of Corals Section 26-3 Section Outline
Section 26-3 Fertilization occurs in the open water, producing many diploid zygotes. Sperm (N) Egg (N) Haploid Diploid FERTILIZATION MEIOSIS Male medusa (2N) Zygote (2N) Polyp Budding polyp Young medusa Female medusa (2N) Each zygote grows into a ciliated larva. The larva eventually attaches to a hard surface and develops into a polyp. Swimming larva The polyp buds to release young medusas. Adult medusas reproduce sexually by releasing gametes into the water. Jellyfish Life Cycle