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Effects on Mitosis

APBIO-E2VDAY

Soybeans grown in soil infected with fungal pathogens were analyzed. It was discovered that lectin, a protein, was found to be in high concentration around the soybean roots. The apical meristem was analyzed, and 1000 cells were compared to soybean root cells without the influence of lectin. The following information of observed data was recorded:

Interphase Mitosis Table 1: Onion Root Tip Observed Values

Interphase Mitosis
Control 780 220
Treated 355 645

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A chi-square test was performed, analyzing the difference between cells treated with lectin in mitosis and control cells in mitosis. The chi-square value was greater than 3.84, where p = 0.05 and degrees of freedom = 1.

Which of the following can be concluded from this data?

A

There was no statistical difference between observed and expected values, and therefore, the deviation between the lectin-treated cells and the control cells was due to chance alone.

B

There was a statistical difference between the lectin-treated cells and the control cells, inferring that lectin causes an increase in mitosis and may have cancerous effects.

C

There was a statistical difference between lectin-treated cells and control cells, implying that lectin causes cells to enter the $C_0$ phase of the cycle.

D

There was no valid conclusion from this data since the chi-square test should use three degrees of freedom since there were four categories to compare, not two.