The Perpetual Perch!

Kate Salsky Pre-Ap Biology March 12th, 2014 - VU

Objectives:

The purpose of this lab is to learn about the body systems of a perch through dissection. Dissection gives the student the opportunity to observe the placement of organs and their relationships to one another.

Background Information:

Perch are members of the class Osteichthyes, home to bony fish. Fins help the perch move quickly through the water and move without rolling over, and are one of the many adaptations the perch acquires. The shape of the perch's body could be described as streamlined, and it is built to move easily through the water. These adaptations have helped the perch survive, and are what we mainly study, along with their body systems.


  • scientific genus: Perca
  • habitat: small ponds, lakes, streams, or rivers
  • predators: herons, hawks, turtles, bullfrogs
  • prey: algae, plankton, aquatic insects
  • niche: freshwater water bodies

Dissection:

Circulatory System: At A Glance

All vertebrates, including the perch, have a closed circulatory system. Closed circulatory systems have the blood enclosed at all times within vessels. Blood is constantly being pumped by a heart through vessels, and doesn't fill body cavities. The heart of a perch only has 1 atrium and 1 ventricle, resulting in a single loop circulatory system. The blood is pumped to and from the gills, as well as going around the rest of the body and back to the heart. Blood is pumped throughout the body through its many arteries, and is pumped back to the heart through veins. The organs involved in this system are: the heart, the veins and arteries, and the gills.

  • Heart- muscular organ helping blood to circulate
  • Atrium- wall layer in heart, assists in the circulation of blood
  • Ventricle- thick wall layer in heart, assists in the pumping of blood
  • Gills- four pair of respiratory organs that are able to take in water to exchange oxygen and ammonium as it circulates over the gills. Then the water reaches the filaments and are converted to aid the perch in respiration as well as circulation.

Human Impact:

Yellow perch are a very popular food fish in the midwestern U.S. and most of the markets for perch are located in that region, particularly in the vicinity of the Great Lakes. Even though this market for perch has acted as population control for the species, no substantial changes have been made in the population patterns due to fishing.