Notes from NEET topper
Phylum chordata
The phylum being described is Phylum Chordata, a significant and diverse group of animals that includes humans and all other known animals and birds. One distinguishing feature shared by all chordates is the presence of a notochord, alongside other characteristic traits such as a dorsal nerve cord, post-anal tail, and pharyngeal slits, which appear at various stages in their life cycles.
Phylum Chordata is categorized into three subphyla:
Urochordata: This subphylum encompasses organisms like tunicates or sea squirts, which are marine filter feeders with relatively simple body structures.
Cephalochordata: Cephalochordates, such as lancelets, are small, marine organisms that maintain chordate characteristics throughout their entire life cycle.
Vertebrata: The largest and most diverse subphylum, Vertebrata, comprises animals with a vertebral column made of bone or cartilage. This subphylum includes various classes of vertebrates, including fish (Pisces), amphibians (Amphibia), reptiles (Reptilia), birds (Aves), and mammals (Mammalia). Vertebrates are known for their well-developed nervous systems, circulatory systems, and skeletal structures that provide support and protection.
