In this article we will discuss about the meaning and classification of phylum hemichordata. Meaning of Phylum Hemichordata: The animals with notochord constitute the Phylum Chordata. It has a major subdivision, called the Vertebrata or Craniata for possession of vertebral column or cranium. The rest of chordates, namely Hemichordata, Urochordata and Cephalochordata are collectively called the Primitive Chordates or Protochordates. [...]
In this article we will discuss about Continental Drift:- 1. Continental Drift Theory 2. Peninsular India 3. Paleontological Evidence of Continental Drift 4. Physical Evidence of Continental Drift 5. Palaeoclimate 6. Explanation of the Continental Drift Theory in the Light of Vertebrate Distribution. Contents: Continental Drift Theory Peninsular India Paleontological Evidence of Continental Drift Physical Evidence of Continental Drift Palaeoclimate [...]
The upcoming discussion will update you about the difference between protostomes and deuterostomes. Difference # Protostomes: 1. Cleavage: Spiral, determinate or mosaic 2. Blastopore: Mouth develops from blastopore 3. Coelom: Schizocoelic (splitting of mesodermal) 4. Mesoderm: From 4d cell, proliferation 5. Arrangement of coelomic cavities: Variable in number 6. Larval type: Trochophore 7. Larval ciliary bands: Compound cilia from 1 [...]