Perch Dissection Introduction
The Perch
• Scientific Name: Perca flavens
• Size: About 0.3m long and up to 2.3 kg
• Range: Found in lakes and rivers from the Great Lakes to
the Atlantic coast and as far south as South Carolina
• Habitat: Lives concealed among vegetation
• Diet: Feeds on insect larvae, crustaceans, and other fishes
• Reproduction: Female perch lay strings of eggs that are
fertilized externally and the young hatch within days
Anatomical terms
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Anterior: In front of, front
Posterior: After, behind, following, toward the rear
Dorsal: Near the upper surface, toward the back
Ventral: Toward the bottom, toward the belly
Superior: Above, over
Inferior: Below, under
Lateral: Toward the side, away from the mid-line
Medial: Toward the mid-line, middle, away from the side
Rostral: Toward the front
Caudal: Toward the back, toward the tail
Label the arrows as Anterior, Posterior,
Dorsal, or Ventral
Important External Perch Body Parts to
Know
• anal fin - the fin on the lower
side of the body near the tail
• caudal fin - the tail fin
• dorsal fin - the fin on the
upper side of the body
– Spinous Dorsal =anterior dorsal
– Soft Dorsal = Posterior Dorsal
• pectoral fin - each of the
paired fins on either side of
the body, near the head
• ventral fin (Pelvics) - each of
the paired fins on the lower
side of the body, near the
head
Important External Body Parts to Know
• lateral line - a series of sensory pores (small openings)
that are located along the sides of fish -they sense
vibrations in the water
• mouth - the part of the body which the fish uses to
catch food - it is located at the front of the body
• eye - sight organs located on the head
• gills - fleshy organs that are used for breathing - they
are located on the side of the head
• Operculum- is a hard plate that is attached to each side
of the head, that covers the gills and is open at the
rear. Aids in gas exchange
• Nostrils- Lead to the olfactory sacs, helps fish smell
Internal Body Parts of the Perch
• Mouth - the first part of the digestive system, where food enters the
body. Chewing in the mouth is the beginning of the digestive process
(breaking down the food).
• Esophagus - the long tube between the mouth and the stomach, the
anterior portion of the digestive tract; it carries food to the stomach.
• Stomach - a sack-like, muscular organ that is attached to the
esophagus. When food enters the stomach, it is churned in an acid
bath.
• intestine - Section of the digestive tract between the stomach and
the anus where absorption of nutrients is carried out and waste is
transformed into fecal matter.
• Anus - the opening at the end of the digestive system from which
feces exit the body.
Internal Body Parts of Perch
• Gall bladder - a small, sac-like organ It stores and
releases bile (a digestive chemical which is
produced in the liver) into the small intestine.
• liver - a large organ located above and in front of
the stomach. It filters toxins from the blood, and
makes bile (which breaks down fats) and some
blood proteins.
• Kidney- organ that eliminates metabolic waste
and maintains the pressure of internal fluids.
• Heart- muscular organ helping blood to circulate,
the fish has a two chambered heart made up of
the atrium and ventricle
Internal Body Parts of a Perch
• Spinal cord - component of the nervous system made
up of a soft fatty substance and forming a cylindrical
stem inside the vertebral column
• vertebral column – movable bony axis made up of
various parts articulating with each other (vertebrae);
it supports the skeleton and contains the spinal cord.
• Muscle- muscular segment of the posterior portion of
the body; its zigzag arrangement contributes to
efficient motion.
• Swim Bladder- used to regulate their vertical position
in the water by controlling the amount of gas that is in
the swim bladder.