What are three characteristics of Chondrichthyes?
Species in this class have paired fins, hard scales, a two-chambered heart, and a pair of nostrils. Most species have 5-7 gill slits on each side of their body. Some species produce egg cases, others give birth to live young.
What is Chondrichthyes biology?
Chondrichthyes are jawed fish with paired fins, paired nostrils, scales, two-chambered hearts, and skeletons made of cartilage (rather than bone). They are divided into two subclasses: elasmobranchii (sharks, rays and skates) and Holocephali (chimaera, sometimes called ghost sharks).
What is the definition of Chondrichthyes and osteichthyes?
Definition. Chondrichthyes refers to a class of fishes that includes those with a cartilaginous skeleton while Osteichthyes refers to a class of fishes that includes those with a bony skeleton.
What makes Chondrichthyes unique?
Key Features of Chondrichthyes Resemble bony fish and terrestrial vertebrates in having jaws and paired appendages. An electroreceptive system is well developed. Endoskeleton entirely cartilaginous. No swim bladder or lung.
Where are Chondrichthyes found?
Members of the Chondrichthyes can be found in nearly all aquatic ecosystems and depths, except the most extreme conditions. But most species are restricted to and specialised for a particular oceanic zone. For example, the skates (members of Rajidae) and angel sharks (Squatinidae) are benthic species.
What do all Chondrichthyes have in common?
Members of Chondrichthyes all lack true bone and have a skeleton made of cartilage (the flexible material you can feel in your nose and ears). Only their teeth, and sometimes their vertebrae, are calcified; this calcified cartilage has a different structure from that of true bone.
How do Chondrichthyes get their food?
Rays eat mostly fishes and invertebrates with their blunt teeth. Some even consume plankton and small organisms. Between the shark and the ray, the two animals prey on nearly everything that swims. Most rays breathe by taking in water through large openings on the upper portion of the head.
Is Chondrichthyes an order?
Chondrichthyes – cartilaginous fishes. Order Torpediniformes (electric rays)
How do Chondrichthyes sleep?
Whatever method they use to breathe, sharks are able to engage in periods of deep rest while still but do not fall asleep in the traditional sense. Lacking eyelids, their eyes remain perpetually open, and their pupils still monitor the motion of creatures swimming around them.
