Classification Symmetry Body Direction

Classification of Humans Kingdom Animalia Phylum Chordata Class Mammalia Order Primates Family Hominidae Genus Homo Species sapiens

Classification of Dogs Kingdom Animalia Phylum Chordata Class Mammalia Order Carnivora Family Canidae Genus Canis Species familiaris

Animal Symmetry Asymmetry—no central axis or point Example: sponge

Animal Symmetry Bilateral symmetry—animal has identical right and left images Example: crayfish

Animal Symmetry Radial symmetry—any plane passing through the center of animal produces identical mirror images Example: sea star

Terms of Direction in the Body Aboral—end opposite the mouth Oral—end containing the mouth

Body Direction Anterior—head end Posterior—tail end

Body Direction Caudal—toward the tail Cephalic—toward the head

Body Direction Distal—away from the point of attachment of a structure on the body (toes are distal to the knee)

Body Direction Proximal—toward the point of attachment of a structure on the body (hip is proximal to the knee)

Body Direction Dorsal—back of an animal

Body Direction Ventral—belly of an animal

Body Direction Inferior—below a point of reference (mouth is inferior to the nose)

Body Direction Superior—above a point of reference (the neck is superior to the chest)

Body Direction Lateral—away from the plane that divides a bilateral animal into mirror images

Body Direction Medial (median)—on or near the plane that divides a bilateral animal into mirror images