Category: Disambiguation A scalpel is a very sharp knife used for surgery as well as various arts and crafts. ... A blade is the flat part of a bladed tool or weapon that (usually) has a cutting edge and/or pointed end typically made of a metal, such as steel used to cut, stab, slice, throw, thrust, or strike. ... Phylum (plural: phyla) is a taxon used in the classification of animals, adopted from the Greek phylai the clan-based voting groups in Greek city-states. ... Typical Classes Subphylum Urochordata - Tunicates Ascidiacea Thaliacea Larvacea Subphylum Cephalochordata - Lancelets Subphylum Myxini - Hagfishes Subphylum Vertebrata - Vertebrates Petromyzontida - Lampreys Placodermi (extinct) Chondrichthyes - Cartilaginous fishes Acanthodii (extinct) Actinopterygii - Ray-finned fishes Actinistia - Coelacanths Dipnoi - Lungfishes Amphibia - Amphibians Reptilia - Reptiles Aves - Birds Mammalia - Mammals Chordates (phylum Chordata) include the vertebrates, together with... Scientific classification or biological classification refers to how biologists group and categorize extinct and living species of organisms. ... Families Asymmetronidae Branchiostomidae The lancelets (subphylum Cephalochordata, and traditionally known as the amphioxus) are a group of primitive chordates. ... Families Asymmetronidae Branchiostomidae The lancelets (subphylum Cephalochordata, and traditionally known as the amphioxus) are a group of primitive chordates. ... The Lancet is one of the oldest and most respected peer-reviewed medical journals, published weekly by the Lancet Publishing Group, part of Reed Elsevier. ... A medical journal is a scientific journal devoted to the field of medicine. ... See also Gothic art. ... Isometric view of a typical arch a complete idiot is a curved structure capable of spanning a space while supporting significant weight (e. ...