Perch Digestive System Mia Hoeve Digestive System Organs ● Mouth- Food enters and is ripped apart by sharp teeth ● Gill Rakers- Short; used to filter zooplankton ● Stomach- Muscular and elastic; digestion begins here ● Pylorus- Sphincter that prevents premature movement of food boils out of stomach ● Pyloric Caeca- Finger shaped pouches; absorb nutrients and secretes digestive enzymes Digestive System Organs ● Liver & Pancreas- Secrete enzymes that break down fats and other various chemicals that aid in digestion ● Intestine- Completes process of digestion and nutrient absorption ● Anus- Releases nitrogenous waste ● Kidneys- Filter blood waste and produce dilute urine for excretion Food Obtained ● Perch are carnivorous fish and eat other animals ● Perch feed on smaller fish, shellfish, and insect larvae ● Perch’s teeth slant backwards, making it easier for the fish to strain tiny particles of food Food Digested ● Mouth is where food enters the body ○ There it is ripped apart by sharp teeth ● Esophagus is where food is moved after ● Stomach food is digested further ● Pyloric Caeca (finger shaped pouches) secrete digestive enzymes and absorb nutrients ● Liver & Pancreas add enzymes and various chemicals as food moves through Digestive tract ● Intestine completes process of digestion and nutrients absorption ● Anus releases nitrogenous waste ● Kidneys filter blood waste and produce dilute urine for excretion Nutrient Absorption & Food and Waste Elimination ● Most of the absorption is done in the intestine although it begins in the pyloric caeca ● Fish excrete both solid and liquid wasted to remove toxic substances like ammonia from their body ● The kidney is the fish’s primary excretory organ ● It removed waste products from the body and also helps maintain the correct balance of salts and water in the fish Structural Adaptations ● Slimy skin prevents perch from being grasped easily ● Perch eggs attach to vegetation to keep them stable until hatching ● Light colored belly gives predators a difficult time to see them from down below ● Stocky, torpedo shaped body for quick takeoff ● Swim bladder contains gas; keeps fish from sinking or floating in the water Digestive System Adaptations ● Specialized teeth (palatines) used to eat small fish ● Gill rakers (small filters in gills) used to ingest and filter zooplankton .