Palpable Perch

Circulatory made Simple

Benjamin Schwierking

Molecule Master

Ms. Mitcham

Pre-AP Biology

6th Period

A Brief Beginning

Perch, or Perca, are freshwater fish belonging to the kingdom Animalia, phylum Chordata, class Actinoptyergii, order Perciformes, and the family Percidae. Perch obtain oxygen by breathing water through their gills, a feathery structure behind the eyes. Perch have a caudal (tail) fin for movement, two dorsal (back) fins for stabilization and turning, an anal (bottom) fin for the same reason, two pelvic (side) fins for up and down movement, and two pectoral (stomach) fins for turning. Perch have a special organ known as the swim bladder that is filled with air to help it float.

The Optimal Objective

Students will learn about the internal and external anatomy of the perch with a special emphasis on the circulatory system. Students will also learn the perch's ecological role.

Revolutionary Evolutionary Relationships

Perch are bony fish most related to sharks and rays.

Harmful Human Impacts

Fishing perch is a source of food and sport for many people. However, over fishing can cause unintentional consequences in a perch's ecosystem. The animals that eat perch would starve, while the animals that are eaten by those perch would prosper and eat everything below them in the food chain. Pesticides that run into a perch's habitat can also have consequences. Because of a phenomenon known as biological magnification (illustrated by the picture), pesticides magnify by 1000% for every trophic level energy is transferred to. Simplified, this means that if a perch containing a pesticide like DDT is eaten by a bass, which in turn is eaten by an eagle, the eagle will have much higher proportions of that pesticide in its body than the perch, which can cause it to die.

Feasibly Fun Facts

  • Perch do not have eyelids.
  • Most perch weigh about one pound, the largest perch caught was more than four pounds in the Delaware River in 1865.
  • When perch feel threatened, they raise their spiny fins.
  • Perch lay between 4,000 and 40,000 eggs.
  • Perch lay eggs in strings.
  • Male perch are more brightly colored than females.
  • Perch sometimes eat their eggs.
  • Perch has high amounts of cholesterol.

Catching Perch and other Collosal Fish

Fish at 0:58

Docile Dissection

The Crazy Circulatory System

A perch has a closed circulatory system, meaning that it has capillaries. The circulatory system is also a single circulatory system, meaning that blood takes a single loop around the body, and all blood passes through the heart every circulation. A fish heart has two parts- an atrium, which holds blood for a short period of time before it is pumped out of the heart, and a ventricle, which pumps blood through a series of contractions and expansions.

Spectacular Sources


Hatch, Jay T., and Nicole Paulson. "Fishes of Minnesota-Yellow Perch." Fishes of Minnesota. University of Minnesota, 23 Oct. 2002. Web. 09 Apr. 2014.

Palande, Leena. "Perch Fish Information." Perch Fish Information. IBuzzle, 29 June 2010. Web. 09 Apr. 2014.

"Perch." Wikipedia. Wikimedia Foundation, 04 Aug. 2014. Web. 09 Apr. 2014.


Fish Phylogeny. Digital image. BBC, n.d. Web. 9 Apr. 2014.

Hainey, R. Biological Magnification. Digital image. Biological Magnification. EDUC551RHainey, 2014. Web. 9 Apr. 2014.

Nile Perch. Digital image. Nile Perch Photos. Animal Planet, n.d. Web. 9 Apr. 2014.

Odino, Martin. Eagle catching fish. Digital image. Stop Wildlife Poisoning. Wildlife Direct, 13 July 2009. Web. 9 Apr. 2014.

Perch life cycle. Digital image. Wetland Information. Australia, 22 Mar. 2013. Web. 9 Apr. 2014.

Perch swimming. Digital image. Wikipedia. Wikimedia Foundation, n.d. Web. 9 Apr. 2014.


Dunkinson, Matt. Escargot. N.p.: Vimeo, 2013. Video.


Fish and Fishing Games. N.p.:, n.d. Online Game.