deoxyribonucleic acid, desoxyribonucleic acid, DNA(noun) (biochemistry) a long linear polymer found in the nucleus of a cell and formed from nucleotides and shaped like a double helix; associated with the transmission of genetic information.
But even adults don't often know what a notochord is. A notochord is a primitive beginning to the backbone. It appears in embryos as a small flexible rod made from cells from the mesoderm, which is one of the three layers of cells of embryos. Notochords are only found in the phylum chordata, a group of animals that includes humans.
Invertebrates are the animals that do not have a backbone or the vertebral column.Animals without the notochord are invertebrates. Most of the animals are invertebrates. The term invertebrates is a prefixed form of a Latin derived word ' Vertebra' .' Vertebra' means joint in general, specifically it means ' the joint of the spinal column of the vertebrate' . It id coupled with the prefix in meaning not or without, which conveys the meaning ' those that lack veterbrae' .ost of the animals are invertebrates. The term invertebrates is a prefixed form of a Latin derived word ' Vertebra' . ' Vertebra' means joint in general, specifically it means ' the joint of the spinal column of the vertebrate' .