Chapter 24 Introduction to Animals 24 1 Animal

Chapter 24 Introduction to Animals 24. 1 Animal Characteristics Support § Invertebrates § Exoskeletons § Hard or tough outer coverings that provide a framework of support § Protect soft body tissues § Provide protection from predators

Chapter 24 Introduction to Animals 24. 1 Animal Characteristics Support § Vertebrates § Endoskeletons § Protect internal organs § Provide support for the body § Provide an internal brace for muscles to pull against

Chapter 24 Introduction to Animals 24. 1 Animal Characteristics Movement § The evolution of nerve and muscle tissues enables animals to move in ways that are more complex and faster than organisms in other kingdoms.

Chapter 24 Introduction to Animals 24. 1 Animal Characteristics Reproduction § Fertilization occurs when the sperm penetrates the egg to form a fertilized egg cell called the zygote. § Internal fertilization § External fertilization

Chapter 24 Introduction to Animals 24. 1 Animal Characteristics § Asexual reproduction means that a single parent produces offspring that are genetically identical to itself. § Budding § Fragmentation § Regeneration § Parthenogenesis

Chapter 24 Introduction to Animals 24. 1 Animal Characteristics Tissue Development § Endoderm § inner layer of cells in the gastrula § Ectoderm § outer layer of cells in the gastrula § Mesoderm § layer of cells between the endoderm and ectoderm

Chapter 24 Introduction to Animals 24. 2 Animal Body Plans Symmetry § Similarity or balance among body structures of organisms § Asymmetry § Radial symmetry § Bilateral symmetry

Chapter 24 Introduction to Animals 24. 2 Animal Body Plans Cephalization § The tendency to concentrate nervous tissue and sensory organs at the anterior end of the animal

Chapter 24 Introduction to Animals 24. 2 Animal Body Plans Body Cavities § Coelomates § Have a fluidfilled cavity with tissue formed from mesoderm that lines and encloses the organs in the coelom

Chapter 24 Introduction to Animals 24. 2 Animal Body Plans Body Cavities § Pseudocoelomates § Have a fluid-filled body cavity that develops between the mesoderm and the endoderm rather than developing entirely within the mesoderm

Chapter 24 Introduction to Animals 24. 2 Animal Body Plans Body Cavities § Acoelomates § Have solid bodies without a fluid-filled body cavity between the gut and the body wall

Chapter 24 Introduction to Animals 24. 2 Animal Body Plans Development in Coelomate Animals § Protostomes § The mouth develops from the first opening in the gastrula. § Deuterostomes § The anus develops from the first opening in the gastrula.

Chapter 24 Introduction to Animals 24. 2 Animal Body Plans Segmentation § Segmented animals can be “put together” from a succession of similar parts. § Can survive damage to one segment § Movement is more effective

Chapter 24 Introduction to Animals 24. 3 Sponges and Cnidarians Sponges § Sponges do not develop tissues. § Water and waste materials are expelled from the sponge through the osculum.

Chapter 24 Introduction to Animals 24. 3 Sponges and Cnidarians Filter Feeder § Food particles cling to the cells. § Digestion of nutrients takes place within each cell.

Chapter 24 Introduction to Animals 24. 3 Sponges and Cnidarians Reproduction § Reproduce asexually § Fragmentation § Budding § Gemmules § Reproduce sexually § Eggs remain within a sponge. § Sperm are released into the water.

Chapter 24 Introduction to Animals 24. 3 Sponges and Cnidarians § Have one body opening and two layers of cells § Outer layer functions in protecting the internal body § Inner layer functions mainly in digestion

Chapter 24 Introduction to Animals 24. 3 Sponges and Cnidarians Reproduction § Two body forms § Polyp § Medusa

Chapter 24 Introduction to Animals 24. 3 Sponges and Cnidarians § The two body forms of cnidarians can be observed in the life cycle of jellyfishes.

Chapter 24 Introduction to Animals

Chapter 24 Introduction to Animals 24. 3 Sponges and Cnidarians Cnidarian Diversity § Hydroids § Jellyfishes § Sea anemones and corals