What makes us fishes?

1. What makes us fishes?

2. Do Now – Reading Check • What structure in humans serves the same function as gills in fish? • What is the function of the lateral line in fish? • What are 3 of the 6 characteristics that make a fish a fish?

3. Do Now Answers • Lungs • Pick up vibrations in water to make fish more aware of their surroundings • Cold-Blooded, Breath using Gills, have fins and scales, have a slime coat, have a lateral line, fish are aquatic.

4. What are Fish – Quick Review • They have gills – they allow fish to remove O2 from water. • Fish have Scales and Fins • Scales can be used to determine the age of fish • Fish have a Lateral Line • Used to feel vibrations in water to make them more aware of their surroundings • Fish create mucous • Reduces friction in water and protects them from parasites and disease. • Fish have a Swim Bladder • They help fish regulate their depth in water • Fish are Cold-Blooded • Body temperature is controlled by their environment

5. Basic Fish Anatomy - External

7. Basic Fish Anatomy - Internal

8. Breakdown of Bony Fishes • Actinopterygii– Ray-finned Fishes • Sarcopterygii – Lobe-finned Fishes

9. Sarcopterygii: Lobe-finned • Members of this class of fish were the ancestors of amphibians and other land animals. • Their swim bladder functions for both buoyancy AND can function as lungs, also use pneumatic sacs to function as lungs • Teeth often present and have true enamel • Fins have homologous structures to modern day terrestrial animal limbs. Bones and muscles move out into the fins.

10. Sarcopterygii : Lobe-Finned Coelocanths Australian Lungfish

11. Actinopterygii: Ray-finned Fishes • There are 3 grades of Actinopterygii, the most abundant are Teleosts • Teleosts make up 96% of all living fish • Swim bladder moved away from any function for respiration, used only for buoyancy. • Fins are flexible, controlled by muscles in body, fins are supported by spines rather than bones

12. Actinopterygii: Ray-finned Fish