In the previous lesson students examined cell size as it relates to efficiency of cellular activity. Students learned that the smaller cells were more efficient based on the ration of the cell's surface area to its volume.
To begin this lesson, students will respond to the following prompt:
The class will get into small groups of 3-4 students to discuss their responses. After a minute, the groups will have an opportunity to share their thoughts with the rest of the class in a whole group discussion.
After an in-depth analysis of the question and the various responses, the class came to a conclusion: the cells that experience the most damage will be replaced most often and undergo mitosis at the fastest rate.
It is important to prompt or guide the students to dig deeper in their understanding of cell division, but try to encourage your students to develop their rationale independently!
Students will get out a sheet of paper to record important details of the Lecture Notes highlighting the details of mitosis. The objective of the lesson is for students to understand the process of cell division as it relates to contributing to the differentiation of cell types and maintaining complex organisms. The process of cell division enables a variety of cell types to exist in order to allow plants and animals to survive.
The ninth grade Biology students developed the following pneumonic device to remember PMAT . . . don't let you dog pee on the mat.
P - prophase
M - metaphase
A - anaphase
T - telophase
Students do not need to take the time to sketch the diagrams that are referred to in the lecture notes presentation because they will be creating models of each stage of mitosis later in the lesson.
Students will organize into groups of 5 and assign the each member a phase in mitosis. For this activity, students will assign their topic based on their birth order:
I use the idea of oldest to youngest as a fun way for students to interact and learn more about each other outside of our Biology curriculum. If left to decide on their own, the same outgoing students always go first. This strategy encourages students who are normally very passive to go first and be heard by their peers.
Students will use their lecture notes and their textbook to guide the creation of the clay model for their assigned phase of mitosis. Once the students have completed their models, they will need develop a written narration that explains what is occurring in the cell during each phase.
Student group work will be assessed using the Modeling Mitosis Rubric.
This video clip provides an example of the students' completed clay models and their corresponding narrations for each phase.
As a Final Review of mitosis, the teacher will use the LCD projector to display the images of plant and animal cells in various stages of mitosis that were part of the lecture notes. Students will observe the slides and shout out the correct responses. The teacher will ask for student volunteers to explain why the slide appears to be the phase of mitosis. If there is confusion, the teacher will make sure to clarify any details before the students leave for the day.
As homework, students will complete this reinforcement activity. (will add later!)
Students are also encouraged to visit the www.cellsalive.com and www.biology.arizona.edu (The Biology Project) for additional opportunities to review the stages of mitosis.