KINGDOM ANIMALIA Characteristics of Animals

Seven Levels of Taxonomic Classification Kingdom Phylum Class Order Family Genus Species

Seven Levels of Taxonomic Classification for the… Kingdom- Animalia Phylum-Chordata Class-Mammalia Order-Primates Family-Hominidae Genus-Homo Species-sapiens Human

Seven Levels of Taxonomic Classification for the… Kingdom- Animalia Phylum-Chordata Class-Mammalia Order-Carnivora Family-Felidae Genus-Panthera Species-leo Lion

Seven Levels of Taxonomic Classification for the… Kingdom: Animalia Phylum: Chordata Class: Mammalia Order: Xenarthra Family: Myrmecophagidae Genus Tamandua Species: tetradactyla Collared Anteater

Seven Levels of Taxonomic Classification for the… Kingdom: Animalia Phylum: Cnidaria Class: Hydrozoa Order: Capitata Family: Milleporidae Genus: Millepora Species: alcicornis Fire Coral

Kingdom Animalia All animals are multicellular, mitochondrial heterotrophs—they have multiple cells with mitochondria and they rely on other organisms for their nourishment. Most animals ingest their food and then digest it in some kind of internal cavity.

Animal Species Somewhere around 9 or 10 million species of animals inhabit the earth. About 800,000 species have been identified.

Animal Phyla Biologists recognize about 36 separate phyla within the Kingdom Animalia. Animal Phyla Web Page

Major Animal Phyla

Animal Movement Most animals are capable of complex and relatively rapid movement compared to plants and other organisms.

Animal Reproduction Most animals reproduce sexually, by means of differentiated haploid cells (eggs and sperm). Most animals are diploid, meaning that the cells of adults contain two copies of the genetic material.

Animal Sizes Animals range in size from no more than a few cells (like the mesozoans) to organisms weighing many tons (like the blue whale). a mesozoan blue whale

Animal Habitats Most animals inhabit the seas, with fewer in fresh water and even fewer on land.

Animal Cells Animal cells, like all eukaryotic cells, have internal structures called organelles that serve specific functions for the cell. Animal cells lack the rigid cell walls that characterize plant cells.

Animal Cell Diagram

Animal Bodies The bodies of most animals (all except sponges) are made up of cells organized into tissues. Each tissue is specialized to perform specific functions. In most animals, tissues are organized into even more specialized organs.

Animal Symmetry The most primitive animals are asymmetrical. Cnidarians and echinoderms are radially symmetrical. Most animals are bilaterally symmetrical.

Radial Symmetry …applies to forms that can be divided into similar halves by more than two planes passing through it. Animals with radial symmetry are usually sessile, free-floating, or weakly swimming.

Bilateral Symmetry …applies to forms that can be divided into similar halves by only one plane passing through it. Animals with bilateral symmetry are most well-suited for directional movement.

Radial vs. Bilateral Symmetry

Cephalization Bilateral Symmetry usually has led to cephalization—the process by which sensory organs and appendages became localized in the head end of animals.

Evolutionary Trends If we analyze the basic body plans of animals, we find that they illustrate evolutionary trends. Four major “advances” (in order): 1.Multicellular body plan 2.Bilaterally symmetrical body plan 3.“Tube-within-a-tube” body plan 4.Coelomate body plan

3 Major Bilateral Body Plans 1.Acoelomates 2.Pseudocoelomates 3.Coelomates Each plan consists of 3 cell layers: endoderm, mesoderm, ectoderm (triploblastic)

Acoelomates These animals have no other cavity than the gut. They are often called the “solid worms.”

Pseudocoelomates These animals have a body cavity (the pseudocoelom) which is not completely lined with mesoderm. The “tube within a tube” body plan. This category is also composed of mostly worms.

Coelomates These animals have a “true coelom” lined with mesodermal peritoneum. Most animals are coelomate.

Protostome vs. Deuterostome Protostomes – mouth first Deuterostomes – anus first