Fish
Kingdom Animalia
Phylum Chordata
Subphylum Vertebrata
Jawless Fishes
Cartilage Fishes
Bony Fishes
Jawless Fish - (hagfish and lamprey
No true backbone, jawless, cranium, cartilage skeleton
Characteristics of fish
Aquatic
Ectothermic
Gills
Most have paired fins
Dorsal fin (balance)
Pectoral fin (steering)
Pelvic fin (steering)
Anal fin (balance)
Caudal fin (forward swim)
Lateral Line System
Lateral Line System � - senses vibrations in the water
Fish Anatomy - Organ Systems
(1) Liver, (2) stomach, (3) intestine, (4) heart, (5) swim
bladder, (6) kidney, (7) testicle, (8) ureter, (9) efferent duct, (10) urinary bladder, and (11) gills.
Respiratory System
Gills use countercurrent exchange for oxygen
OPERCULUM - covers the gills
Swim Bladder - found in ray finned, bony fish
Used for flotation and for air storage
Circulation heart → gills → body
2 chambered heart
Single loop circulation
Fish have a two chambered heart – blood is passed over the gills where it picks up oxygen → SINGLE LOOP
Single Loop vs Double Loop Circulation
Synthesis: Compare the circulatory system of a fish to the circulatory system of a mammal. What are similarities? What are differences?
Discuss with your lab partner and write down your answer, be prepared to share with the class.
Digestive System
Esophagus → Stomach → Pyloric Caeca → Intestine → Anus (vent)
4. The Nervous System
- Cerebrum - thinking, voluntary activities�- Cerebellum - coordination�- Medulla Oblongata - basic functions, organs�- Optic Lobe - vision
medulla
SCALES
Scales cover and protect the fish
Mucus on scales help fish swim
The rings on a scale tell the fish’s age
Check Yourself
1. Fish have _____________________ loop circulation.
Mammals and birds have ____________________ loop circulation.
2. The two chambers of the fish heart are the _______________ and ______________
3. Blood leaves the heart goes to the gills and then to the ____________ before it returns to the heart.
4. The covering of the gills is the _________________________
5. __________________________ increase surface area of stomach for digestion.
6. The part of the brain used for thinking and learning is the ______________________
7. The part of the brain used for balancing is the ______________________
8. The _________________ ___________ system senses vibrations.
9. Fin used for forward motion is the __________________________________
10. _____________________ exchange pulls oxygen from the water into the blood of a fish.
Fish Reproduction
Spawning – fish lay eggs that are fertilized externally
Some fish bear live young - FRY (baby fish)
This 1 minute video shows a lemon shark give birth to live young.
Some sharks lay eggs.
Types of Reproduction
Take notes over this short video that explains spawning behavior in salmon.
How is the respiration rate of fish affected by changes in temperature?
This lab will ask you to lower the temperature of a fish and measure the number of breaths it takes.