Kidney stones are composed of crystals that usually form in the kidneys or ureters (the tubes that carry urine from the kidneys to the bladder); most are very small but some can be as big as a golf ball. Most small stones cause intense flank and pelvic pain as they irritate the ureters as they pass through them.idney stones are composed of crystals that usually form in the kidneys or ureters (the tubes that carry urine from the kidneys to the bladder); most are very small but some can be as big as a golf ball. Most small stones cause intense flank and pelvic pain as they irritate the ureters as they pass through them.
Osteichthyes /ËÉstiËËÉªkÎ¸i.iËz/ , also called bony fish, are a taxonomic group of fish that have bone, as opposed to cartilaginous, skeletons.The vast majority of fish are osteichthyes, which is an extremely diverse and abundant group consisting of 45 orders, and over 435 families and 28,000 species.It is the largest class of vertebrates in existence today.Osteichthyes are divided into the ray-finned fish (Actinopterygii) and lobe-finned fish (Sarcopterygii).The oldest known fossils of bony fish are about 420 million years ago, which are also transitional fossils, showing a tooth pattern that is in between the tooth rows of sharks and bony fishes.t is the largest class of vertebrates in existence today. Osteichthyes are divided into the ray-finned fish (Actinopterygii) and lobe-finned fish (Sarcopterygii).
Osteichthyes are a very diverse group of bony fish. They are Ectothermic, which means they depend on the surrounding environment for their body temperatures. Osteichthyes live in all types of fresh and salt waters.steichthyes (Bony Fish) are the most species-rich and morphologically diverse lineage of all vertebrates. 1  brain. 2  spinal cord. 3  cranial nerves. 4  spinal nerves. 5  sensory organs 6  -. eyes-good eyesight. 7  no eyelids, thus permitting a maximum amount of. 8  light. 9  ears-no external opening.