What is the meaning of the following-
1) Notochord
2) Diploblastic and triploblastic organisation
Notochord is a chord like structure, which is present during the embryonic stages of chordates. This is one of the primary characteristics of Chordates. It is flexible in nature.
Diploblastic organization means having two germ layers ectoderm, and endoderm. Triploblastic organization means having three germ layers ectoderm, mesoderm and endoderm.