fish

  1. Otolith bone: fish ear bone, functions in maintaining balance in fish, but also, like a tree trunk, has growth rings that can be used to age the fish and see years of boom and bust

  2. Tail types:

    1. Homocercal: a symmetrical tail fin, top portion is the same as bottom. Found in many fish like perch

    2. Heterocercal: a type of sickle like tail fin, not symmetrical with the larger portion on the top. Found in sharks and other predatory fish

    3. Diphycercal: a tail fin that tapers to a central point in the center. Found in lungfish

  3. Eye: receives visual images, response to stimulus

  4. Nostril: chemoreception (odor detection), connects to olfactory bulb in brain

  5. Mouth: beginning of digestive tract, food intake

  6. Operculum: unique to bony fish. Bony plate with muscles attaching that protects the gills and moves to force water in mouth over gills. Active fish have feud operculum so must swim constantly to move water over gills

  7. Pectoral fin: maintain orientation, stability in locomotion

  8. Pelvic fin: maintain orientation, stability in locomotion

  9. Anal fin: maintain orientation, stability in locomotion

  10. Caudal fin: aka homocercal fin, provides thrust for locomotion

  11. Lateral line: detects movement in the water via vibration. Also, pressure, temperature, and salinity

  12. First dorsal fin: orientation and stability in locomotion

  13. Second dorsal fin: orientation and stability in locomotion

  14. Gills: respiratory gas exchange

  15. Brain: motor coordination, sensory info integration, autonomic functions

  16. Spinal cord: connects impulses from brain to peripheral nerves

  17. Kidney: removes nitrogen waste, connects to bladder

  18. Swim bladder: regulates buoyancy by storing gasses

  19. Gas gland of swim bladder: secretes gasses into swim bladder to maintain buoyancy

  20. Oval body of swim bladder: reabsorbs gasses from swim bladder to maintain buoyancy

  21. Ovary: egg storage and maturation

  22. Bladder: storage old nitrogenous waste from kidney until expulsion from body

  23. Spleen: houses microphage cells (phagocytosis) and other immune cells

  24. Duodenum: first portion of small intestine, nutrient absorption, fat emulsification, toxin neutralization

  25. Pancreas: secretes digestive enzymes and hormones

  26. Cardiac portion of stomach: beginning of digestion, food storage

  27. Pyloric ceca: increase surface area for nutrient absorption

  28. Pyloric portion of stomach: digestion of food

  29. Liver: metabolizes fats (emulsification) and carbohydrates by secreting bile (alkaline) into duodenum, also neutralizes toxins

  30. Urogenital opening: expels urine and eggs/sperm in females, posterior to the anus

  31. Anus: secretes waste from digestive tract

  32. Blood flow

    1. Atrium → Ventricle → Bulbus arteriosus → Ventral aorta → Afferent branchial arteries → Efferent branchial arteries → Dorsal aorta → Arteries → Capillaries → Veins → Hepatic portal (and other) veins → Sinus venosus → Atrium