Perch Physiology
External Anatomy
Dorsal Fins – The fin on the top
Pelvic Fin – The fins that are right under the gill slits.
Pectoral Fins – the fins that are bottom front.
Anal Fin – The fins that are by the anus
Caudal Fin – The back fins
 All the fins push against the water to create
movement
Operculum – Directs water over the gills. Also protects
the gills.
Lateral Line and the Dorsal Line both are sensitive to
pressure and temperature changes. They allow the perch
to detect movement.
Muscular System
Myomere – A muscle fibre bundle.
Digestive System
Mouth – The opening to the digestive system.
Esophagus – The tube connecting the pharynx to the
stomach.
Stomach – Storage and digestion of food.
Intestine – Absorbs nutrients from the food.
Liver – Creates material that aids in digestion. The liver
also helps to remove toxic material from the inside of the
fish.
Respiratory System
Gill Rakers – Filters out food and helps protect the gills
Gills – Allows exchange of 02 and CO2 from between
the blood and the water.
Gill Filaments – The gill filaments together make up a
gill.
Circulatory System
Atrium – Directs the blood to the ventricle.
Ventricle – pumps the blood to the body.
Nervous System
Brain
Olfactory tract - Smell
Optic lobe - Sight
Spinal cord – All other body functions.
Other
Kidney – Filters the blood to make “pee”.
Bladder – Storages “pee”.
Swim Bladder – This structure inflates and deflates to
help the fish sink or float (become more or less buoyant)
in the water.