What are the characteristics of the phylum Chordata?
Phylum Chordata possesses the following characteristic features: It is a longitudinal, cartilaginous rod running between the nerve cord and the digestive tract. It acts as a support for the nerve cord and is replaced by the vertebral column after the embryonic stage in all vertebrates.
Which is the smallest Chordata in the world?
Pikaia gracilens, known only from the Middle Cambrian Burgess Shale lagerstatte of British Columbia, is a small (~4 cm) species that is likely important for understanding the features of early chordates, if not cephalochordates.
Why is the notochord replaced in the adult Chordata?
It is also known as Tunicata because the body of an adult is enclosed within a tunic made up of cellulose -like substance known as tunicin. Notochord can be seen only in the larval stage and disappears in the adults. The nerve cord present in larva is replaced by a dorsal ganglion in adults.
Where is the tail located in a chordate?
All Chordates have these openings on the lateral sides of the pharynx at some stage of their life. It is an extension of the body to the anus. In chordates, the tail is composed of skeletal muscles which help in locomotion in fish-like species. It is absent in most of the adult Chordates.
Characteristics of Chordata. Animals in the phylum Chordata share five key chacteristics that appear at some stage during their development: a notochord, a dorsal hollow (tubular) nerve cord, pharyngeal gill arches or slits, a post-anal tail, and an endostyle/thyroid gland (Figure 2).
Which characteristic is common to all chordates?
All invertebrate chordates share four main characteristics: a notochord, a dorsal nerve tube, a post-anal tail, and pharyngeal gill slits. All of these characteristics are observed at some point in chordate development.
What do Chordates include?
1 Answer. Chordata is a familiar phylum that includes organisms like mammals, fish, birds, reptiles, and amphibians (all vertebrates); sea squirts (tunicates); and lancelets (cephalochordates). All chordates have a notochord, a dorsal nerve cord, and pharyngeal slits at some point in their development.
Are humans Chordata?
Practice Question The dorsal hollow nerve cord is part of the chordate central nervous system. In vertebrate fishes, the pharyngeal slits become the gills. Humans are not chordates because humans do not have a tail. Vertebrates do not have a notochord at any point in their development; instead, they have a vertebral column.
Are fish chordates?
Chordates are animals with backbones. Animal groups in the chordate phylum include fish, amphibians, reptiles, birds and mammals. Animals with backbones are the most highly evolved groups of animals, the most complex and complicated. They have interior skeletons and have bilateral symmetry. They have more advanced brains.