14 Apr 2012. Home INR monitors are simple to use and provide accurate results. You don't need any medical experience or technology skills to perform the simple INR test. The listed monitors are all approved for professional and home use allowing you immediate INR test values resulting in improved care.
Lampreys and hagfishes are the only jawless vertebrates to survive today. They both have a round mouth and for this reason are often referred to as cyclostomes. They are the most primitive of the vertebrates. By primitive, a biologist means that they are the least changed from the first vertebrates.1  They have no paired pectoral (shoulder) or pelvic (hip) fins. 2  Their notochord persists for life, never being completely replaced by a backbone even in the lampreys.3  They have no scales.y primitive, a biologist means that they are the least changed from the first vertebrates. 1  They have no paired pectoral (shoulder) or pelvic (hip) fins. 2  Their notochord persists for life, never being completely replaced by a backbone even in the lampreys. 3  They have no scales.
Among craniates, the most primitive are the hagfishes. Hagfishes do not have a bony skull. Instead their skull is made up of cartilage, a strong but flexible substance that consists of the protein keratin. Hagfishes are the only living animal that have a skull but lack a backbone or vertebral column.The first known craniates were marine animals that evolved about 480 million years ago. These early craniates are thought to have diverged from lancelets. As embryos, craniates have a unique tissue called the neural crest.raniates, like all chordates, develop a notochord that is present in hagfishes and lampreys but which disappears in most vertebrates where it is replaced by the vertebral column. All craniates have an internal skeleton, also called an endoskeleton.