Cell division is separated into mitosis and meiosis.

Meiosis and mitosis are two different types of cell division. Chromosomes from the parent cell split into two nuclei during mitosis, creating two daughter cells. Chromosomes alter during mitosis in a number of ways, including duplication, condensation, and attachment to spindle fibers found in the cytoskeleton of the cell (Nicholas 2014). The two identical daughter cells are produced as a result of these spindle fibers pulling on opposing sides of the cells. Prokaryotic cells do not often undergo mitosis because they lack a nucleus, and instead divide through alternative processes including binary fission (Schatten 2013). The rate at which mitosis occurs in eukaryotic organisms differs considerably based on the ability of the cell to break down the nuclear envelope. Generally, mitosis is preceded by the S-phase of the cell cycle, referred to as the interphase stage. It is in this stage where DNA undergoes replication, followed by cytokinesis which ensures the parent cell gives rise to daughter cell with all cell components and organelles (Schatten 2013). Mitosis is divided into a number of phases. The completion of one phase signals the start of the next one. These stages include prophase, metaphase, anaphase, and telophase. Each of them is defined by distinct characteristics. Throughout prophase, the cellular material, including the nucleus is separated, chromatin condenses, and spindle fibers begin to form. For the duration the cell is in the metaphase phase, the chromosomes are arranged at the equator, supported by spindle fibers from both ends (Nicholas, Rao, & Gennerich 2014). Throughout anaphase, daughter cells or sister chromatids are separated and move to different ends of the cell. In telophase, the cell components are arranged before undergoing cytokinesis. This paper investigates the number of a cell undergoing mitosis in a root of the onion tip.
Methods
Onion tips from a tender age are observed from the microscope for the various stages or phases of mitosis. Once all of the phases were identified, an estimate of the total number of cells presents within the cell was provided. The class totals and the other team totals were also recorded during the process.
Results
White fish Blast cells Onion root tips
Your total % of cells (your total) Class total % of cells (class total) Your total % of cells (your total) Class total % of cells (class total) Interphase 57 47% 945 53% 25 69% 1349 53% Prophase 44 36% 555 32 3 8% 795 31% Metaphase 6 .05% 143 8% 4 11% 186 7% Anaphase 5 .04% 68 3% 2 5% 86 3% Telophase/ Cytokinesis 8 .06% 74 4% 2 5% 144 6% Total Cells 120 1785 36 2560
White fish Blast cells Onion root tips
Your total Class total Your total Class total
number of cells observed in interphase 57 945 25 1349
Total number of cells counted in the sample (n) 945 1785 36 2560
Proportion of cell cycle spent in interphase (p)

(p = # in interphase/n) 0.06 0.53 0.69 0.53
Standard Error (SE)

SE = 0.0413 0.062 0.0166 0.0313
Error factor (EF)

(1.96 x SE) 0.010185 0.1252 0.03253 0.0613
Convert p to percent

(p x 100) 6% 53% 69% 53%
Convert EF to percent

(EF x 100) 4.13% 6.2% 3.2% 3.13%
Lower limit of 95% CI
(p (percentage) - EF) 1.87 46.8% 65.8 49.87
Upper limit of 95% CI
(p (percentage) + EF) 7.0185 59.2% 72.2% 56.13%
95% Confidence Interval (range: lower limit to upper limit) 4.98-7.0185 46.8%-59.2% 65.8-72.2% 49.87-56.13%

Discussion
Considering the class data:
What percentage of the cell cycle was spent in the interphase by the cells of the onion root?
The percentage of cells under the interphase cycle for the onion root cell is 69%
What percentage of the cell cycle was spent in interphase in the whitefish blastula?
The percentage of cells under the interphase cycle for the whitefish blastula cell is 47%
Did the 95% confidence intervals for the two species overlap at all?
The 95% of the total number of cells present in all phases inter-lapped, while the individual number of cells in the various phases had some differences, especially in the various phases.
If they overlap, then any difference you found between the two species is NOT statistically significant; if the 95% CIs do NOT overlap, then the difference is statistically significant.
Did your class observe a statistically significant difference in the amount of time spent in interphase by the two different species?
Data in the interphase phases differed significantly, and therefore the results were not statistically significant.
Were your personal results similar to the class results? How were they similar/different?
My personal results were similar to the class results in the different phases, though the totals of the class differed significantly with the class values.
What trend did you observe in the 95% CI as sample size increased?
An increase in the sample size directly results in a decrease in the 95% confidence interval. This is because of the standard error which defines the standard deviation and sample population decrease with an increase in sample size.
Why might the combined data from the whole class be more meaningful than your results alone?
The combined data from the class is more meaningful compared to the individual result. It has a higher sample size as compared to the individual results. This reduces the existing variability in the data, reducing the standard error. Therefore, the class data provides meaningful insights, compared to individual results.
What normally happens within a cell during interphase? Why might you expect this phase to occupy a greater percentage of the cell cycle in some cells than in others?
Interphase is considered to be the resting phase of the cell where the cell accumulates all the products and factors to be used during the entire cycle. The cell can only start this cycle once all components are accumulated. Cells differ considerably in the manner in which they accumulate products, required in the cell cycle.
Consider the class data measuring the percentage of the cell cycle spent in each of the phases of mitosis (PPMAT, not including interphase) by each cell type.
Which phase is the longest?
Prophase takes a longer period compared to all the other phases.
Is it the same in both species?
Yes.
What events happen during this phase?
The formation of mitotic spindle, chromatin condensation from DNA, and the disappearance of nuclear envelope are the key features of prophase.
Why does this phase take longer than the other phases?
Prophase takes a longer period as compared to the other phases because the microtubules have attached to the chromosomes. This microtubule have to be detached before the start of the process.
Both root tips and embryos are growing rapidly. If you were looking at non-growing tissue, such as a leaf in the middle of summer or mature cells in your spleen right now, would the percentage of cells in each phase be different? Explain your answer, including which phases of the cell cycle, would have more or less cells.
Mitosis is an ongoing process within a cell. Therefore, the prophase phase is still going to be expected to be the longest phase as compared to the rest.
Conclusion
Mitosis is a critical cell division process that occurs in eukaryotic cells. It is defined by five key stages, including interphase, prophase, metaphase, anaphase, and telophase. Interphase and prophase are considered as the longest phases. Increasing the sample size significantly raises the validity and reliability of the data used.

Works Cited
Nicholas, P. Matthew., Rao, Lu, & Gennerich, Arne. Mitosis. Methods in molecular biology. 2014 Retrieved from http://doi.org/10.1007/978-1-4939-0329-0
Schatten H. Mitosis. Brenner's Encyclopedia of Genetics, pp. 448-451., 2013 Retrieved from http://doi.org/10.1016/B978-0-12-374984-0.00962-1