DTSE 2007: Lesson 3.3

NESTED STUCTURE 3

LESSON 3.3

TITLE: Mitosis

INTRODUCTION: In this lesson, students will be learning about the process of normal cell division, mitosis. Students have learned about cancer and the inefficiency of the cancer treatments. By this time students should also know that cancer is the result of abnormal cell division. Students have been given the assignment of creating a better cancer treatment. In this benchmark lesson, should help students understand the process of mitosis so that they can further analyze the regulation process of normal cell division to be able to create their own theoretical cancer treatments. In this lesson, students will use an internet websites as well as computer based simulations to discover mitosis. In partners, they will complete a mitosis packet. By the end of the lesson, the teacher should relate mitosis to the overall unit of cancer through a group discussion. For homework, students will be given the assignment of creating their own mitosis diagrams.

OBJECTIVES:

•	Students will be able to describe the process of normal cell division. •	Students will be able to draw the stages of mitosis including cell structures present at each stage. •	Students will be able to identify the definitions of key terms such as chromosomes, kinetochore, cytokinesis, cell plate, spindle fibers, chromatid, centrioles, centromeres, diploid, and hapliod cells in regards to mitosis. •	Students will be able to apply their knowledge of the mitosis cycle to create their own mitosis diagram.

STUDENTS PRECONCEPTIONS:

Students hold some preconceptions about the topic of cell division. Many students understand the cell makes a copy of itself but could not remember the steps or the process. Some students do not realize that the actual DNA is being replicated and then an exact copy is given to each daughter cell. Throughout the lesson and discussion, these preconceptions will be addressed.

MATERIALS:

•	10 – 15 computers with internet access •	Copies of the mitosis packet for each student •	Textbooks

PREPARATION:

In order to prepare for this lesson, the teacher must be very knowledgeable on the topic of mitosis in order to best be able to answer students’ questions. In this lesson plan, a teacher information sheet has been provided. It includes facts about each cycle as well as definitions. A complete mitosis cycle has also been provided for teacher use. Also, the instructor should take a look at the interactive websites to make sure they are up and running. This lesson plan would not be as effective and interesting if students could not access them.

TIME: 1.5 hour

ACTIVITIES:

•	Have the teacher open up the class reminding the class of what they had learned the previous lesson. Make sure to ask the following questions: o	What is cancer? o	Can you treat cancer? o	How effective are the treatments? o	Are the treatments specific? o	Do the treatments cure all the patients? o	What are the side effects of some of the treatments? o	What makes cancer cells different from normal cells? o	How does a normal cell divide? o	What characteristics does a “good” treatment have? o	What do you think you need to further understand about cancer to come up with an effective treatment? These questions should be thought about in a group discussion.

•	The next set of questions that should be thought about as a group include the following: o	What do you need to know to design a new treatment? (Hopefully the teacher can lead the students to realize that a better understanding of cell division is needed.) o	What about cell division do you need to know? o	What controls cell division? o	How does this relate to cancer? The teacher should help the students understand that to further study the cause of cancer, they need to study normal cells first. They should already know that cancer is caused by abnormal cell growth. Before the students can analyze what is wrong, they need to understand what normally occurs. The instructor should inform the class that they will be studying cell division today. •	Break the students up into groups of two or three. It depends how many students are present and the amount of computers with internet access. •	Pass out the mitosis worksheet. Tell the students to look through the following websites and complete the worksheet. They may use their textbook for additional resources. Each individual student must complete their worksheet themselves.

•	Websites about mitosis:

http://www.biology.arizona.edu/vocabulary/mitosis_meiosis/mitosis_meiosis.html http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/M/Mitosis.html http://www.iknow.net/CDROMs/cell_cdrom/cell3.html

•	Interactive mitosis websites:

http://www.cellsalive.com/cell_cycle.htm http://www.cellsalive.com/mitosis.htm http://www.biology.arizona.edu/Cell_bio/tutorials/cell_cycle/cells3.html

•	Give the students at least 30 minutes to complete the packet. Make sure the instructor walks around to answer any questions the students may have. Also, try to facilitate conversation about mitosis. •	Once the mitosis packet is completed, have the teacher facilitate a group discussion. The teacher should go over the mitosis worksheets by calling on students to present their answers to different questions in the packet. Along with going over the mitosis packet, the instructor mention the following points: o	All cells come from preexisting cells o	Through mitosis an exact replica of the parent cell is created. o	 Mitosis is a well regulated process and without this regulation, normal cell division cannot occur o	Normal cell division is needed for everyday life •	For homework, students should draw the mitosis cycle. The mitosis cycle should not be “copied” from the book. Instead, emphasize to the students to use many sources to create this diagram. This will hopefully stress learning and not just memorization. A colored diagram with labels should be handed in the next day for grading.

ASSESSMENT: An informal assessment can be done when the teacher is walking around and observing students completing the mitosis packet in partners. A more formal assessment can be done by the teacher when going over the mitosis packet. The teacher should observe the answers given by the students to the questions on the worksheet. Lastly, the diagram of the mitosis cycle can be graded by the instructor the following class. Considering the students are not allowed to copy the cycle exactly from the book, combining other resources will facilitate learning.