The document summarizes a student's lab experiment examining the cell cycle phases in onion root tip cells. The student observed 10 fields under a microscope and counted the number of cells in each phase of mitosis. A table shows the counts for each field and totals. Graphs display the overall observed counts and expected counts calculated from literature. Calculations compare the observed and expected counts, finding no significant difference. The conclusion is that interphase occurs most frequently while anaphase is rarest, consistent with literature.

1. Ploy Phataraprasit
18/11/09
IB Biology SL
Period 7
Onion Cells
Introduction
The five major phases, Interphase, Prophase, Metaphase, Anaphase, and
Telophase appears in Onion Cells. Onion root undergoing mitosis is the stage in
which class will examine. In this investigation, class will take a look at ten different
fields and identify cells in to five different phases. Student then would infer the length
of time cell spend in each phase and compare the data with the Arizona University.
Data Collection and Processing
Table 1: Onion Cells in different phase with calculation in different Field
Data Collection
Field Interphase Prophase Metaphase Anaphase Telophase
1 19 3 0 1 1
2 23 3 1 0 1
3 20 4 1 0 1
4 22 2 1 1 0
5 21 0 0 0 1
6 12 1 1 0 1
7 18 1 1 0 0
8 18 0 0 0 0
9 11 0 0 0 1
10 14 1 0 1 1
Data Processing
Overall 178 15 5 3 7
Expect 180 19.5 2.17 1.3 4.3
… 0.05 1.25 4.50 4.00 2.25
x² 12.05

2. Graph
Figure 2: Overall number of cells being observed
Figure 3: Expected number of cells being calculated
Data Calculation
Interphase:
= 208

3. 0.05
Prophase:
= 208
1.25
Metaphase:
= 208
4.50
Anaphase:
= 208

4. 4.00
Telophase:
= 208
2.25
Interphase + Prophase + Metaphase + Anaphase + Telophase
= 1.25 + 0.05 + 4.50 + 4.00 + 2.25
x² = 12.05
Difference not significant 0.01
Conclusion and Evaluation
Overall, the data is significantly different with the University of Arizona, due
to the fact that the data is shown to be in rejected areas of . This result shows that
Interphase is the most occurrence phase/cycle, which shows that this process is the
most significant to cells. On the other hand, Anaphase seems to be the phase that
happens rarely. The difficulty in this lab is the calculation of each phase, meaning the
expected values of each phase. However, in all, the data collection methods were easy
to understand.