Defining the Difference Between Prokaryotic and Eukaryotic Cells--An alternative to direct instruction.

Objective: To create criteria to describe the difference between prokaryotic and eukaryotic cells.

Materials:
5 Microscopic Slides of Prokaryotes
5 Microscopeic Slides of Eukaryotes (Diversity is recommended)
Microscopes
Microscope with Camera (Optional)
Slide Show of Prokaryotic and Eukaryotic cells
CPS Electronic Response System

Lesson Plan
(1) Explain to the students that are two basic types of cells, one is called prokaryotic and the other is eukaryotic.
(2) Break down the origin of the words pro = early, first eu= true karyo = nut/kernal ic = pertaining to. Using these greek/latin root words create a superficial definition of theses terms:
Prokaryotic: Pertaining to an early first nut (cell).
Eukaryotic: Pertaining to a true nut (cell).
(3) Using the initial definition as a guideline/clue. Have each student visit each of the 10 microscopes in pairs. At each station there is either a prokaryotic or eukaryotic cell. Students should create a description of the cells--being as detailed as possible as they move through the stations.
(4) Once they have completed the stations, their task to organize the 10 slides into two categories based on the physical descriptors they identified. The end result should have the students' having two catergories (prokaryotic/eukaryotic) with 5 slides in each categories. They should have used descriptors such as a small or big, simple or complex, no internal structures or internal structures, primitive or advanced in design, etc. If students are not capable of organically coming up with these descriptors, create a data table that allows them to be guided to these conclusions.
(5) After students have finished creating their two categories, determine which one should be assigned the title prokaryotic or eukaryotic.
(6) Optional Step--If you have access to a digital camera, then you can take pictures of the slides in advance to review the slides and debate on the physical characteristics of each cell used to categorize them into two categories.
(6) Once a common definition of prokaryote is created: simple, small, no nucleus, no organelles, first cell and eukaryotic: complex, large, nucleus, organelles and true cell. Use those terms to show students 10 new slides on the smart board/ppt presentation. Have students using their definition deterine if these new and unknown slides are prokaryotic or eukaryotic. Optional--use an electronic response system to formatively assess if students can recognize the difference between these two different types of cells.
(7) Conclusion--have students hypothesize what type of organisms are prokaryotic and eukaryotic--give them 2-3 minutes. Have students share out, the realization or goal is that only bacteria are prokaryotic and everything else is eukaryotic.

Time: Before Class Prep 30 Minutes limiting technology, 60 minutes using the digitial microscope and creating the questions for the CPS response system.

Class Time: Introduction 5 minutes, Microscope Stations 30 Minutes, Definition 5 minutes, Conclusion and Share Out 10-15 minutes.