BIL 151 – Mitotic Index Worksheet – CONTROL Samples:
Team Number:
Team Members:
Instructor:
Lab section code:
Day and time:
Your team will receive a set of micrographs of chromosome squashes from eight
control onion root tips that have been treated as per the protocol your team devised.
Divide the labor among team members appropriately, so each team member counts an
equal number of slides. You may confer together to decide whether a particular cell is in
any given mitotic phase.
Enter your raw data in the tables below.
Table Templates: CONTROL Raw Data
Record your raw data (counts of cells in each phase of mitosis in control onions) in the tables below.
CON Sample #1
Field 1
# Prophase cells
# Metaphase cells
# Anaphase cells
# Telophase cells
# Interphase cells
Field 2
Field 3
Field 4
TOTAL
CON Sample #2
Field 1
# Prophase cells
# Metaphase cells
# Anaphase cells
# Telophase cells
# Interphase cells
Field 2
Field 3
Field 4
TOTAL
CON Sample #3
Field 1
# Prophase cells
# Metaphase cells
# Anaphase cells
# Telophase cells
# Interphase cells
Field 2
Field 3
Field 4
TOTAL
CON Sample #4
Field 1
# Prophase cells
# Metaphase cells
# Anaphase cells
# Telophase cells
# Interphase cells
Field 2
Field 3
Field 4
TOTAL
CON Sample #5
Field 1
# Prophase cells
# Metaphase cells
# Anaphase cells
# Telophase cells
# Interphase cells
Field 2
Field 3
Field 4
TOTAL
CON Sample #6
Field 1
# Prophase cells
# Metaphase cells
# Anaphase cells
# Telophase cells
# Interphase cells
Field 2
Field 3
Field 4
TOTAL
CON Sample #7
Field 1
# Prophase cells
# Metaphase cells
# Anaphase cells
# Telophase cells
# Interphase cells
Field 2
Field 3
Field 4
TOTAL
CON Sample #8
Field 1
# Prophase cells
# Metaphase cells
# Anaphase cells
# Telophase cells
# Interphase cells
Field 2
Field 3
Field 4
TOTAL
Calculating Mitotic Indices
The Mitotic Index (M) is the proportion of mitotic cells in a sampled cell population.
M = nm/N
nm = total number of mitotic cells in the sample
N = total number of cells counted in the sample
Calculating Mitotic Phase Indices
A Mitotic Phase Index (MP) is a measure of the proportion of cells in a particular phase of mitosis
in a sampled population of mitotic cells.
MP = np/ nm
np = # of cells in prophase in the sample
nm = total number of mitotic cells in the sample
Refer to your raw data in the tables above to calculate a mitotic index and mitotic
phase indices for each of your control samples. Enter them in the table below.
Provide a table legend that includes treatment data, data collection dates and
all other pertinent information.
Table 1.
Control
Sample #
Mitotic
Index (M)
Prophase
Index (Mp)
Metaphase
Index (Mm)
Anaphase
Index (Ma)
Telophase
Index (Mt)
1
2
3
4
5
6
7
8
Submit the completed worksheet to your instructor at the end of the lab
session.
Each team member should also retain a copy of this completed worksheet.
You will perform a statistical analysis of your treatment and control data
as a team assignment.