OBJECTIVES
At the end of this study, student should be able to: outline the general characteristics or features of vertebrates classify the phylum vertebrata give the general characteristics of the fishes draw a well labeled diagram of a bony fish outline the adaptive features of fishes.
Vertebrata
The Vertebrata is a subphylum of the Phylum Chordata. The Chordates have a notochord, a flexible rod of tightly packed cells, a tubular nerve cord (dorsal) and gill slits at some stage in their life histories. Note: a backbone or vertebral column replaces the notochord in vertebrates.
Characteristics A bilaterally symmetrical body, divided into a head, a trunk and a tail. In Most vertebrates, a neck joins the head to the trunk. An internal skeleton or endoskeleton of bone and cartilage, with a backbone or vertebral column made up of a series of small bones called vertebrae. A well-developed central nervous system with a brain (within a brain case) and a spinal chord (dorsal position).Well-developed sense organs. A ‘closed’ blood system made up of a muscular heart (ventral position). Two pairs of limbs (tetrapods.)Kidneys for eliminating body wastes. Skin may be naked or have a covering of scales, feathers or hairs. Vertebrates are divided into five classes: - Pisces - Amphibia - Reptilia - Aves, and - Mammalia.
- Lecturer : Nnamdi Chukwu Amadi