Is Hematodinium spp. the Culprit?



Students will be provided with mock crab hemolymph samples and will use gel electrophoresis to determine if Hematodinium DNA is present. Prior to this lesson, students should have an understanding of the structure of DNA and biotechnology techniques, such as gel electrophoresis, that are used to "fingerprint" an organism.


Students will be able to use gel electrophoresis in order to determine if the Blue crab has been infected by Hematodinium.

Lesson Materials

  1. Case of the Crown Jewels Towson University Center for STEM Excellence ( ) loaner kit. This kit provides the teacher with the gel electrophoresis equipment, pipettes and chemicals (including mock DNA samples). The kit can be requested at a time for a 10 day period. Teachers must have training before loaning materials from the lab. The teacher must change of the labels on the provided DNA samples to read: Positive control for Hematodinium, Negative control, Crab hemolymph 1, crab hemolymph 2, etc.
  2. Student Lab worksheet
  3. Digital camera. (optional)
  4. Printer (optional)


  1. Students will complete the lab "Is Hematodinium the Culprit" by following a series of step-by-step directions for loading and running the gel.
  2. Students will photograph their gel to later be printed and analyzed (optional) or sketch their results with paper and pencil.


MdBio Case of the Broken Beaker,

Student Handout,

Maryland State Standards

The student will test a working hypothesis. (NTB) 
The student will select appropriate instruments and materials to conduct an investigation.
The student will identify appropriate methods for conducting an investigation (independent and dependent variables, proper controls, repeat trials, appropriate sample size, etc.).
The student will recognize safe laboratory procedures.
The student will demonstrate safe handling of the chemicals and materials of science. (NTB)
The student will learn the use of new instruments and equipment by following instructions in a manual or from oral direction. (NTB)
The student will use analyzed data to confirm, modify, or reject an hypothesis.
The student will create and/or interpret graphics (scale drawings, photographs, digital images, field of view, etc.).
The student will explain how a genetic trait is determined by the code in a DNA molecule
The student will estimate degrees of relatedness among organisms or species.
The student will conclude that populations grow or decline due to a variety of factors. At least — Linear/exponential growth Carrying capacity/limiting factors Species specific reproductive factors (such as birth rate, fertility rate) Factors unique to the human population (medical, agricultural, cultural) Immigration/emigration Introduced species. 

The Blue Crab: Callinectes Sapidus

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pile of cooked crabs