2. Bell Ringer & Lab Goals
Review of mitosis stages via video
http://www.teachersdomain.org/resource/tdc02.sci.life.stru.dnadivide/
Complete the worksheet—Call on individual students for the answers
Discuss characteristics of mitosis stages in preparation of the lab
The goal of the lab is to observe the different stages of cellular growth
including the entire process of mitosis. You will work with your lab partner
seated next to you to locate and view the onion cell root tips under the
microscope.
3.
4. Mitosis Lab Instruction
Quiz the students about lab techniques and safety using this
worksheet.
Ross, how do we act when we conduct experiments?
◦ We must conduct ourselves in a responsible manner and follow all instructions
carefully.
Megan, what else is important to keep everyone safe?
◦ We must never work alone or without the teacher and we have to keep the
aisles clear. Oh, yes, we must keep our hands away from our face, eyes and
mouth while conducting the experiment.
Dillon, how do we handle the slides?
◦ We hold the slides by the edges and not put our fingers directly on the slides.
If it is chipped, we call you, Ms. Gee, immediately.
Leslie, can you tell us about the microscope?
◦ Yes, we have to handle it properly like we already know how to do.
And finally, Megan, what do we do when we finish the lab?
◦ We wash our hands.
5. Essential Question &
Student Hypotheses
Do all phases of the
cell cycle require the
same amount of
time?
Dillon says, “ If I
count the onion
cells, then I predict
Bradley says, “If I to see more cells
see the onion in Interphase than
cells, then I will in Telophase.”
see more of
Prophase.”
Megan says, “ If I
count the onion
cells, then I will
see all phases of
mitosis.”
6. Ms. Gee’s Inquiring Minds…
“Dillon, what do
you see in this • I see the cells in Prophase.
quadrant?”
“Megan, How
does each cell get • I see the spindles forming.
a complete set of This is the beginning process
chromosomes?
Do you see this for the new cell to get all of
phase in your the chromosomes needed.
samples?”
7. Compiling & Documenting Data
For those with
We will use the
access to a laptop In additional to
Now it is time to laptop and an
at home, please your charting, let’s
record your data excel file to chart
email the chart to answer the
and prepare for the your data. Each
me and you can following questions
presentation of student has been
add it to the overall to supplement your
your findings. assigned a time to
spreadsheet in lab findings:
use the laptop.
class.
8. Student Responses to Lab Data
Questions
Sydney, what information did you learn when charting your data?
• We all had different data, but there were more cells in iIterphase than the
other phases.
Bradley, what phase of the cell cycle is the longest? Why?
• Hey, my hypothesis is right!! It seems that the cells in Interphase were the
longest. This is where the cell grows and replicates the DNA and centrioles.
Megan, What would happen if a cell did not make a copy of the
DNA before mitosis?
• If a cell did not make a copy of the DNA before mitosis, there would be one
cell with no DNA—does that mean it is not a cell?
Dillon, what happens if mitosis is not followed by cytokinesis?
• Without cytokinesis, the cytoplasm would not split into two distinct cells.
There would be only one cell with two identical nuclei.
9.
10.
11.
12. What Did You Learn Today?
(Your parents will ask)
Class, what did you find Dillon, Megan and
interesting about the Bradley, tell me how
observation of the onion your results compared
cells? to your hypothesis?
Dillon—I found out that my hypothesis is
correct! I saw more cells in Interphase, the
longest stage of mitosis.
Growth continues through the process of
mitosis. There are different phases that Megan—I did see all the phases of the cell
have to occur for cells to multiply— cycle and mitosis. There were not as many in
Interphase, Prophase, Metaphase, Telophase or Cytokenisis.
Anaphase, Telophase and Cytokinesis.
Bradley—My data showed that I saw more in
Interphase than in Prophase, as I predicted.
