MITOSIS LAB: Making More Cells

 

Purpose: To build models of the steps of cell division (mitosis), and to ex­amine dividing cells in an onion root tip.

 

Materials:

            COLORED PAPER                 TOOTHPICKS                       ONION SLIDE

            SCISSORS                              RULER                                    CUP

            GLUE                                      STRING                                  THREAD

 

Procedure:

 

1.         Review the steps of mitosis in your textbook.

 

2.         While you watch the slides on the "movie screen," draw a single cell in each of the steps (phases) of mitosis. Draw these in the order they oc­cur in the cell. Number the phases #1 - #4. Label the "cell parts" on your drawing from the chart below.

 

3          On a piece of smooth-edged notebook paper (SENBP), answer questions #1 - #5.

 

Now make your models of mitosis. ONLY MITOSIS, not Interphase!!

 

The chart below lists what you need and how to make each part.

 

CELL PARTS

MATERIALS TO USE

SIZE TO MAKE IT

HOW MANY YOU NEED

Cell Wall

Dark color paper

12 cm x 7 cm

5

Cytoplasm

Light color paper

11 cm x 6 cm

5

Nucleus

Another color paper

Size of cup lid

3

Chromosomes

String

2.5 cm each

15

Spindle Fibers

Toothpicks

|1/2 toothpick each

as needed

Nuclear material

Thread

|15 cm long per cell

| one per "new" cell

Cell Wall

Dark Paper

.5 cm x 6 cm

| 1 - between "new" cells

 

4.         Put the models together by gluing a "cytoplasm" paper on top of a "cell wall" paper so a little cell wall sticks out around the edges.

 

5.         Each cell you make will have 3 chromosomes. Use your textbook, a model, if available, and your cut out cell parts to make your own model of the stages of mitosis. Glue the proper cell parts to each stage (phase).

 

6.         Arrange your models in the correct order and glue them to a sheet of paper. BE SURE YOUR NAME IS ON YOUR PAPER!! Lay the completed models around the side of the room to dry.

 

7.         Now do the matching questions (#6 - #10) on your SENBP.

 

QUESTIONS: DO NOT WRITE ON THIS PAPER!

 

1.         In which stage of mitosis did you first see spindle fibers?

2.         In which phase of the cell cycle was a nucleus present?

3.         Where did the chromosomes move in METAPHASE?

4.         How many new cells does each dividing cell form?

5.         Where did the chromosomes move in ANAPHASE?

 

Match the phase of the cell cycle with what happens:

 

6.         PROPHASE                            A. DNA replicates, cell gets ready to divide

7.         METAPHASE             B. Nucleus re-forms and cell becomes to cells

8.         ANAPHASE                           C. Chromosomes line up in center of cell

9.         TELOPHASE                          D. Chromosomes separate

10.       INTERPHASE             E. Chromosomes become thick and dark