Animalia - A Very Diverse Kingdom

Kingdom Animalia Characteristics All animals share the following five characteristics: 1. Eukaryotic cells with a nucleus and membrane bound organelles 2. Multicellular 3. Reproduce sexually (mostly) 4. Heterotrophic 5. Motile, at least for part of their life

Animals are also called metazoans. Animals are taxonomically grouped based on three main features: 1. Number of body layers 2. Type of body cavity 3. Body symmetry Kingdom Animalia Features

The 3 main layers appear very early in embryonic development. Each body layer develops into different tissues. In humans the layers are: 1. Ectoderm – skin, nerves 2. Mesoderm – muscles, blood, kidneys 3. Endoderm – lungs, liver, gut lining Feature 1: Number of body layers

The two main types of body cavities are: 1. Acoelomates – lack a fluid filled body cavity, like flatworms 2. Coelomates –have a fluid filled body cavity that supports organ systems Feature 2: Type of Body Cavity

Feature 2: Acoelomate Body Cavities

Feature 2: Coelomate Body Cavities The evolution of the fluid filled coelom allowed for the development of more complex internal organ systems.

The three main types of body symmetry are: 1. Asymmetric – no distinctive symmetry 2. Radial – body is organized around a central axis. These animals are symmetrical around any central cut. 3. Bilateral – can be cut into two mirror images through a central line. Feature 3: Body Symmetry Top Bottom Back Front

Animal Phyla Animalia phyla are spilt into two major groups based on the presence or absence of a spinal cord. There are 8 invertebrate phyla and only 1 phyla of vertebrates.

Animal Phyla And a video to review what you just learned. watch?v=wd-QnKlfZHI