Bony fish

bony fish or Osteichyes , by Shew Felix

1. Osteicthyes

2. Class Osteichthyes (Gr. Osteon,bone + ichthyos , fish) - also called bony fishes.

3. The earliest bony fishes known from the fossil record date back about 420 million years, to the Silurian period. The group diversified during the  Carboniferous Period .

4. Coelacanth Evolution

5. Bony fishes share several distinguishing features: A skeleton of bone Scales Bony operculum covering the gill openings Lungs or a swim bladder

6. All bony fish have : Bony skeleton 2 chamber heart Cold blooded scales Lateral line

7. Many species of bony fishes first evolved in freshwater and later expanded into marine habitats.

8. Osteichthyes are primitively   ectothermic (cold blooded)

9. There are approximately 25,000 species of bony fishes worldwide.

10. The largest bony fish is thought to be the ocean sunfish ( Mola mola ) which can grow to lengths of up to 11 feet and weights of over 5,000 pounds

11. The longest is the k I n g o f h e r r I n g s or oarfish reaching a record length of 11 m (36  ft )  

12. The smallest bony fish is thought to be the dwarf pygmy goby ( Pandaka pygmaea ) which grows to a whopping length of just about one-third of an inch.  

13. Nektonic – swimmers – control movement against current - move to food - escape predator Movement

14. Kingdom: Animalia Phylum: Chordata Class: Osteichthyes

15. Family tree

16. are  taxonomic   group of fish that have bone in their skeletons. It is the largest class of vertebrates in existence today.

17. BODY PLAN Skeletons of these fishes are made of hard, calcified tissue called bone Typical fish body shape is roughly cylindrical and tapering at both ends Temperature control: Ectothermic

18. Osteichthyes are divided into 2 subclasses: Actinopterygii the ray-finned fish  Sarcopterygii lobe-finned fish

19. Subclass ACTINOPTERYGII contains fishes that are sometimes called the ray-finned fishes because their fins lack muscular lobes .

20. They usually possess swim bladders, gas-filled sacs along the dorsal wall of the cavity that regulate buoyancy.

21. ray-finned fish 

22. Subclass SARCOPTERYGII have muscular lobes associated with their fins and usually use lungs in gas exchange.

23. lobe-finned fish

24. SYMMETRY : Osteichthyes (bony fish) have bilateral symmetry, if you were to cut the fish exactly in half, the right and left side would be equal. they would have the same number of eyes, fins, gills, etc.

25. SEGMENTATION : Osteichthyes have no segmentation . TYPE OF COELOM: There is a coelom present among all osteichthyes . Each Osteichthyes ' coeloms vary slightly, but all have a coelom, which allows them to move more freely through the water .

26. Musculo -Skeletal Fish move through the water with movements of their tail, here different kinds of fish locomotion are illustrated:

27. ENDOSKELETON or EXOSKELETON : Osteichthyes have an exoskeleton, meaning they have an external skeleton that helps protect the internal organs. Bony fish differ from the Chondrichthyes because the bony fish have skeletons actually made of bone. Most bony fish have scales, however, some have armor plating, while others such as catfishes lack any kind of covering over the exoskeleton and thus are considered "completely naked". 

28. Fish swim with rhythmic side to side motion of the body or tail Rhythmic contractions produced by bands of muscle called myomeres Locomotion

29. stomach , intestine, pancreas, liver, pyloric caecae Pyloric caecae – slender tubes that secrete digestive enzymes Plant eaters = long intestine, Meat eaters = short intestines Digestive System:

30. Feeding Filter feeders filter plankton through their gills Tend to be smaller, schooling fish such as herrings, anchovies, and sardines

31. Shape of the mouth lets you know how it eats Top feeder bottom feeder

32. Respiratory System Fish ‘breathes’ oxygen from the water molecules:

33. Fish get oxygen that is dissolved in the water They must get water to flow over gills to do this, called irrigation

34. The gill is supported by cartilaginous or bony structure called gill arch Gill rakers are used as filters to stop food from entering gills Gill filaments contain the capillaries

35. The fish heart is a single loop circulation which has 2 chambers . Blood flows into the gills, picks up oxygen goes to the body and then returns to the heart Circulatory System

36. * Closed circulatory system * Gas exchange happens in the gills

37. Uses actual lungs to breathe and has reduced gills Lungfish

38. * Brain & spinal cord * Olfactory sacs or bulbs located on either side of the head and connected to nostrils (smell) * Taste buds located in mouths or barbels * spinal cord, cranial nerves, spinal nerves, sensory organs - Nervous System

39. - An inner ear is contained in teloests which detects sounds and balance. - A lateral line controls impulse detections and low frequencies. This line contains ciliated nerve cells . - Chemoreceptors are used for sensing smell - Weberian ossicle : in freshwater fish for special acoustic sensory Sensory Organ

40. The blood of marine fish is less salty than the water, therefore they lose water through osmosis To replace it they must drink seawater Regulating Internal Environment

41. Reproduction Fertilization is usually external, but can be internal.

42. Most fish fertilize their eggs externally Spawning - the process of fertilizing eggs (fish reproduction) Fry = baby fish Broadcast Spawning

43. Development is usually oviparous ( egg-laying ; depositing eggs that develop and hatch outside the body as a reproductive strategy)

44. but can be ovoviparity ( eggs are retained in the female, but the embryo obtains its nourishment from the egg's yolk )

45. or viviparous ( born alive, as are most mammals, some reptiles, and a few fish (as opposed to being laid as an egg)

46. Importance: As food, 2. They give by-products. 3. To control diseases .

47. Thank you for listening  God bless 