Observing Cell Division
In this classroom activity, students (individuals or small groups) make microscopic observations of onion root tips. Observations are shared with classmates and discussed. Extended observations are made, with students concentrating on one cell that looks particularly interesting to them. Detailed drawings are made and shared. Discussion of the variation of observations is made while sharing, and questions are recorded on the classroom whiteboard. Small groups then choose a question for further research, conduct research and share their findings.
- observe cells and use appropriate vocabulary to describe them
- use proper techniques of operation of the compound light microscope
- compare and contrast cells in different stages of mitosis
- formulate questions based on observations
- do text/library/internet research to find answers to their questions
- cell division/fission
- nuclear membrane
Context for Use
Time required - 1 hour (+15 minutes to share findings on day 2)
Equipment needed - compound light microscopes, 1 per pair of students
Resource Type: Activities:Classroom Activity
Grade Level: Middle (6-8)
Description and Teaching Materials
1. Provide groups or individual students with access to the microscopes and root tip slides. Observation of cells will need to be made under high power - provide instructions if necessary.
2. Allow 5 minutes for students to make and record initial observations.
3. Bring entire group together and verbally share observations.
4. Allow students to return to their microscopes with instructions to choose one "unique-looking" cell in their field of view. Students make a detailed drawing of the cell and record extended observations about the cell (make BIG drawing and record observations on poster paper).
5. Again bring the entire group together and take turns with groups sharing drawings and observations. Encourage questioning during this sharing time. Record questions on the classroom white board. Display poster papers in room.
6. Provide small groups with a white board and have them choose and record a question to investigate (via text, reference books, or internet). Provide time and resources for groups to conduct their research.
7. When sufficient information has been collected to answer their question, student groups choose a way of displaying their findings on their white board. Share with the entire group.
Teaching Notes and Tips
In the past, we have studied cell division with the traditional approach, that is with ME telling and showing THEM, perhaps with the opportunity for students to observe the process under the microscope or with a computer animation AFTER instruction. This activity BEGINS with the student observation and questioning, characteristics of inquiry learning.
I would ask students to articulate their findings in words and drawings in their daily science journal.
On end-of-unit test, students will label cells in various stages of division.
22.214.171.124.2 Cell division