1. Fish Phylum: Chordata Class Osteichthyes
The Osteichthyes

2. Homework
Read p
1. compare and contrast cycloid and ctenoid scales.
2. How do fish maintain bouyancy in water?
3. How does the body shape of a tuna and a flounder relate to their lifestyle?
4. What do fishes called grazers feed on?
5. Name two bony fish which are filter feeders who feed on plankton.

3. Homework Due Thursday
Read p Answer the following in complete sentences
1. Where are spiracles located and what is their function?
2. What do chloride cells do?
3. Where are fish taste buds located?
4. Define Anadromous and give one species as an example.
5. Name two reproductive strategies fish use in mating.

4. Class: Osteichthyes the bony fishes - 98% of all fishes
Distinguishing Characteristics
Bony skeleton, thin overlapping scales
Operculum
Swim bladder
Terminal mouth
Most w/ fin rays

5. Huge Diversity in the Bony Fish
Think adaptation!
Think niche exploitation!
Think staying alive, getting food, passing on more genes than the next guy!

6. What percentage of fish are bony fish?2%
98%
89%
50%

7. External Structure
As Chordates, fish have an incredible variety of characteristics.
Most are covered with flat scales that fit into pockets in the skin and have a mucus coating.
Some lack scales or have tiny scales. Scales may be cycloid, ganoid or ctenoid types. Some can be reabsorbed if food is scarce.
Scales contain chromatophores that cause color changes for camouflage, mating - species recognition or when stressed. Iridocytes contain reflecting granules.

8. Cycloid
Cycloid scales are thin and overlapping, permitting more flexibility.  Unlike ganoid scales, cycloid scales grow as the fish grows, and in some species, show annual growth rings.

9. Ctenoid
Ctenoid Overlapping scales have tiny teeth called ctenii on the posterior edge that give them a rough texture.

10. Ganoid
Most are diamond-shaped and connected by peg-and-socket joints. In sturgeons, the scales are greatly enlarged into armor plates along the sides and back, while in the bowfin the scales are greatly reduced in thickness to resemble cycloid scales

11. Coloration Chromatophores – w/ pigment – for color
Iridophores – w/ crystals that result in structural colors (result when a special surface reflects only certain colors of light)
Usually silver

12. Chromatophores

13. Iridophores

14. Coloration
Warning coloration – Red Yellow Black or combinations of such colors
Cryptic Coloration – used to camouflage
Disruptive Coloration – used to confuse predators ex. eye spots

15. Warning Coloration

16. Cryptic Coloration

17. Disruptive Coloration

18. Circulation: Closed Circulatory system 2 chambered heart, most ectothermic
Tuna, barracuda and a few others maintain temperature higher (~10o) than environment so technically they are endothermic.

19. Vision: Poor to medium and usually only lateral
Vision: Poor to medium and usually only lateral. The iris is not adjustable and lens protrudes through the pupil.
Some fish can detect and generate weak electrical currents.
This electro-perception is used to communicate in schooling, aids in migration, detecting and stunning prey.

20. Hearing: Aided by the lateral line, the swim bladder and the otoliths (located in the inner ear) detect movements and affect balance.
Smell: Chemoreceptors are found on the mouth, lips, skin and fins.
Most of brain is olfactory lobes use for smell to find food.

21. Designed for Speed
Tuna are exquisitely designed for speed and can swim at 45 mph for long periods.
NOAA
They have a foldable dorsal fin that fits into a groove making it flush with the body to reduce drag when maneuvering.

22. The red blood cell count in tuna is equal to mammals
The red blood cell count in tuna is equal to mammals. – more oxygen more energy!!
Bluefin tuna and sailfish are the fastest fish at nearly at 70 mph.

23. Sun Fish – Slow Moving
The largest bony fish is the Mola Mola (Sunfish).
Molas eat plankton and can weigh pounds. They swim slowly and do not have a fusiform body shape, although it can be 11 ft. long.

24. Adaptations

25. Lionfish – Adaptation – poison spines

26. false eye
Cryptic coloration: false eye on butterfly fish, kelp fish; counter-shading, (dark on dorsal surface and light on ventral); camouflage; aid in survival

27. Eye spot – confuses predators
Adaptation –
Eye spot – confuses predators
Which side is the head on???

28. Surgeonfish - Scalpel for protection

29. Seahorse
Seahorses are beautiful fishes with some remarkable adaptations including hard bony armour on the body, a prehensile tail (which can be used for holding on), binocular vision, excellent camouflage They have both an exo- and endo- skeleton.

30. Green Moray Eel
Must constantly open and close their mouth to pump water through their gills to breathe

31. Coloring for camouflage

32. Adapted for flight
----Escape from predator

33. Mahi Mahi (Hawaiian Name) – fast
notice homocercal caudal tail
AKA: dorado or dolphin fish

34. Adaptation – Spine for protection
The Cowfish

35. – Adaptations, Lure, large mouth expandable stomach
Hairy Angler fish

36. Cells which allow for color change are called
Colorforms
Chromatophores
Changelings
Camofores

37. The only fish with both and exoskeleton and an endoskeleton is the
Green Turtle
Sea squirt
Sea Horse
Gastropod

38. Fish have a __ chambered heart1 2 3 4

39. Adaptations Barbels- Feelers for detection
Triggers, spines, poison – for protection and predation
Schooling – for protection
Coloration – for defense and predation

40. Schooling
Schooling used by many smaller fish population to confuse predators not allowing them to focus on a single fish.
Scientists believe that the coordination in the movement of a school of fish is due to chemical or electrical signals

41. Fin Shapes Homocercal vs. heterocercal tail
High aspect vs low aspect tail

42. Caudal Fin Shape
   Increasing the size of the caudal fin should increase speed; however, increasing size also increases drag
         ii.      ASPECT RATIO gives information on caudal fin efficiency
1.      Aspect Ratio = (fin height)2 / fin area

43. Lunate

44. Round

45. Forked

46. Truncate

47. Homocercal Tail

49. Reproduction

50. Reproduction: sexual, mostly external fertilization called spawning
Gonads - sac contains either sperm or eggs (roe).
Sex reversal is common in reef fish and in deep water fish

51. 3 Reproductive Strategies Only two used by Bony Fish
Oviparous – lay eggs or egg cases
Energy from yolk
Viviparous – bear live young Some Sharks and Rays
Energy from mom
Ovoviviparous – form “egg” but keep inside
Energy from yolk, but inside mom

52. Oviparous
Laying Eggs - spawning
External fertilaization

53. Ovoviparous Eggs Lays Eggs….. And retain them in the body
Mouth Brooders

54. Hermaphroditism male and female gonads
still reproduce with other individuals
more common in deep-sea fishes
Why hermaphroditism?
If you can’t find a female to mate with…….. why not just become a female?
Or If you can’t be with the one you love…. love the one you’re with

55. Sex Reversal sea basses, groupers, parrotfishes, wrasses
individual starts life as a male, changes into a female (or visa- versa)
Why sex reversal?
-In the deep ocean chance meetings of the same species are not wasted with gender issues

56. Bearing live young is referred to as being
Oviparous
Viviparous
Omniviparous
Ovoviparous

57. When the mother retains the fertilized egg it she referred to as being
Oviparous
Viviparous
Omniviparous
Ovoviparous

58. Egg layers are referred to as
Viviparous
Ovoviparous
Omniviparous
Ovipararous

59. How do fish
"Breathe"?

60. Gills help regulate the salt/water balance called osmoregulation.
Respiration: Water containing 02 flows over the gills in a different direction than blood so diffusion is maximized; muscles pump water through gills
Gases from the blood and/or gulped air are used to adjust buoyancy in the swim bladder.
Several gill arches supporting gill rakers and gill filaments are covered by a flap called the operculum.
Gills help regulate the salt/water balance called osmoregulation.
NOAA

61. “Breathing” Counter-current exchange for max diffusion efficiency
Diffusion – the passive transport of gases (O2 and CO2) through a membrane
Hemoglobin – carries oxy in blood
Myoglobin – stores oxy in muscle

62. Gas exchange
The way this taxon does gas exchange is through their gills. Fish take in water through their mouth that contains O2. The O2 goes into the bloodstream. The CO2 from the blood stream is released with the water through the fish’s gills.

63. Gill Structure
Gill filaments – highly vascularised (it has a lot of blood vessels), large surface area
Gill Arch – supports gills
Gill Rakers (Filaments) – projections to keep food out of gills, or modified to catch food
Lamellae – divisions of gill filaments, giving even more Surface area

67. Water
Blood
Water
Blood
Oxygen Exchange through diffusion

68. The Protein which stores Oxygen in the muscle tissue is called
Hemoglobin
Oxyglobin
Myoglobin
Triglobin

69. Blood and Water run ________ in the gill system more maximum efficiency.
Concurrent
Countercurrent
None of the above

70. Structures which support the Gills are called
Gill Rakers
Gill Braces
Gill Bones
Gill Arches

71. The Gills are covered and protected by a flap of skin called the
Operculum
Gill Flap
Epiglottis
Gill Raker

72. The Gills extract ____ gas from the seawater
Carbon Dioxide
Water
Salt
Oxygen