Summer Research Program for Science Teachers


Linda Vales

George W. Wingate High School

Brooklyn, NY



How do cells reproduce?




Subject: Living Environment (Biology)


Grade level: 9th, 10th


Length: 3-42 minute periods


Overview:  This unit is comprised of activities illustrating the process of cell division, which will be related to the follow up lessons on cancer and how the immune system can be used to treat it. A brief review of cells and the functions that take place inside the cells will be conducted at the beginning of the unit.  Students will study the process of cell division through inquiry and also gather information from multiple sources such as the Internet, the use of prepared slides, textbook readings, and prepared transparencies.  Students will be able to connect data collected while doing their experiment in the class with real life situations such as the uncontrollable growth of tumor cells resulting in Cancer.


Day I


Aim: How do cells reproduce?


Instructional Objectives: Students will be able to:


1.      Explain why reproduction of the cell is necessary to the survival of the species.

2.      Identify the stages of Mitosis in the process of cell division and explain what happens in each.

3.      Explain what happens to the chromosome number and DNA during the process of cell division.

4.      Conduct and experiment: cell division in yeast. materials/curricula.



Time allocated: 1 class period-42 minutes

Science Standards: Scientific thinking: s5a, s5f, s6b, s7a, s7d.

                                  [9-12 content Standard C- The cell]



§         Prepared slides and transparencies of cells undergoing Mitosis.

§         Hand out (student worksheet) and charts illustrating the process of Cell Division.

§         Materials necessary to study (through inquiry) cell division in yeast- listed at

§         Microscopes- one for each pair of students



§         Overhead projector

§         LCD projector

§         Computer with internet access

§         Screen



§         Cooperative Learning groups(2-3 students)

§         Lab Experiment

§         Analysis of Data

§         Classroom Presentations by students- using power point, and/or poster board.


Internet Resources:








§         Biology – The Study of Life. Schraer and Stoltze.  Prentice Hall.

§         Any science textbook that contains a section on mitosis.

§         Ready to use Science Proficiency- Lessons and Activities- Mark J. Handwerker, Ph.D. The Center for applied Research in Education.




Teacher: “ Each one of you has brought 2 photo pictures of yourself, a baby-picture and one taken recently.  Take 1 minute and examine both pictures carefully.  Identify and write down at least 3 changes you notices have taken place.”

(Students were asked to bring pictures with them as part of their previous homework assignments).


Teacher: “ How do you explain the changes that have taken place in you from the time you were a baby to the present?”


Elicit from students that one of the major causes of the changes that have taken place is the life process of Growth.


Teacher: “ When you were younger, did any of you ever had a bad fall and scratch your knee, or anywhere on your skin?” 

“ Can you now identify the spot where you got the bruise?”

 “ How did the healing take place?”


Elicit from students that the spot may no longer be visible because of new cells/tissue that have formed and have replaced the dead and damaged ones.       


Review of concepts already learned and connect them to new ones.

§         The cell is the basic unit of structure.

§         The cell is the basic unit of function.

§         All cells come from pre-existing cells.


Question: “ Which process results in the production of more cells from pre-existing  Cells?” 


The process is Cell Reproduction through cell division.


Pivotal Questions:


1.      Why should cells have the ability to reproduce?

2.      What are the stages involved in cell division/reproduction of cells?  How can we explain the changes that are taking place during each stage?

3.      Why is it important and even crucial that each cell (except the reproductive cells) maintain the same number of chromosomes before the process begins and, even after when it is completed?

4.      How does cell division take place in yeast use (fungi)?




Key concepts to study in this unit: Mitosis, Cytokinesis, interphase, prophase, metaphase, anaphase, telophase, Reproduction, mitotic cell division and cytokinesis in plant and animal cells, mitotic cell division in yeast, mitotic cell division in the onion root tip cells.


§         Brief review of the cell: “ before we talk about the reproduction of the cell, let’s review our prior knowledge of the cell.  Take 1 minute and write down at least two concepts you learned when we discussed cells before.”

[Review the basis structure of the cell, two basic types: Prokaryotic cells Vs Eukaryotic cells, Eukaryotic cells: plant cells Vs animal cells, substructures of the cell: the organelles, such as the mitochondria, the chloroplast, the ribosomes, etc.


§         Use of the internet to review the parts of the cell

§         Reproduction of the cell is one of the most important functions that take place in the cell.  It results in growth, and is essential in the repair and synthesis of tissues


§         Definition of Mitosis and its importance in cell division.  Each species has a specific chromosome number, which should always be maintained.


§         Use of Overhead projector and transparencies to study Cell Division: Mitosis, and Cytokinesis.  Students should be made aware that cytokinesis does not always follow mitosis.


Student activity #1


Hand out on the process of Mitosis.

1.      Read the information on Mitosis from the passage.

2.      Examine the illustrations – then complete the observations and analysis section.











































Medial summary


Answer the following questions in your notebook


1.      List the phases of Mitosis

2.      Why is the cell not really at rest during the so-called resting stage?

3.      Why is it important for the cell to duplicate each one of its chromosomes before the cell actually begins to divide?


Student Activity #2


Students will get in their cooperative groups and study prepared slides of Cell division in the onion root tip cells.  Two members of the group will collect the materials needed from the front of the class: Microscopes, lens paper, and the prepared slides


1.      Make a sketch of each of the stages of mitosis in the plant cell- the onion root tip cells that you are viewing.

2.      Write down one change that is taking place in each stage.

3.      Using a compare and contrast matrix, compare and contrast mitosis in the animal cell studied earlier and mitosis in the plant cell.


Final Summary/Guided review


Students will be called upon by random to report to the rest of the class their answers to questions from student activity #2


Homework assignment


1.      Read pages 668-669 from the study of life.  Write a short description of the yeast- the organism we are going to study tomorrow.  Be sure to describe its general characteristics, its mode of nutrition, its mode of reproduction, etc.


2.      Make an outline of how you would set up an experiment to study cell division in yeast.


Day 2


Aim: How does cell division take place in yeast?


The activities that will be conducted in class for this lesson will be adapted from a Lesson found at: (How do cells reproduce?)


The following are lessons (follow up lessons) that will be covered in the same unit as the one above:

§         How is cell division related to Cancer?

§         What are the possible treatments for Cancer? 

§         How can the immune system be stimulated in the treatment of Cancer?


Return to Biology Lesson Plan Menu