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Root Cells

ACTSCI-JQFR2U

A Scientist decides to test the effect the addition of giberellic acid has on root growth in newly planted pea shoots. She sets up an experiment where she will test various concentrations of giberellic acid solution. She sets up five groups of twenty-five plants each. Four of the groups are watered daily with various concentrations of giberellic acid solution, the fifth with water without any additives. The length of the main root was measured every 3 days in each plant and the average of each group was recorded. The results are summarized in the data table below:

$$ \text{ Length of Main Root (cm):} $$

Group # Conc of Gib. Acid (ug/ml) Day 3 Day 6 Day 9 Day 12 Day 15
1 0 2 2.2 2.5 2.8 3.1
2 10 2.1 2.5 2.9 3.3 3.5
3 20 1.9 2.7 3.0 3.5 3.9
4 30 2.2 2.9 3.3 3.7 4.1
5 40 2.0 2.3 2.4 2.4 2.5

If the researcher were to study root cells from a plant from each of the trials of her study, which statement would most accurately reflect what she sees as she studies the root cells under the microscope?

A

The most actively dividing cells would be found in the root from the group #1 plant.

B

The least amount of actively dividing cells would be found in the root from the group #1 plant.

C

The most actively dividing cells would be found in the root from the group #4 plant.

D

The least amount of actively dividing cells would be found in the root from the group #4 plant.