91影视

The bar graph for tooth size contains two rectangular bars for each collection site: one bar for grown in Rhode Island and another for grown in Florida. In the experiment, seeds were collected from four different sites, an independent variable, and thus plotted on the x-axis.

The tooth size varied depending on the seed collection site. Thus, the average area of a single tooth (cm²) is a dependent variable and plotted on the y-axis.

The bar graph for the number of teeth in leaves also contains two rectangular bars for each collection site: one bar for grown in Rhode Island and another for grown in Florida.

The seed collection site is an independent variable in the experiment, so it is plotted on the x-axis.

In contrast, the number of teeth per cm² of leaf area is a dependent variable and hence plotted on the y-axis.

The bar graph for tooth size suggests the leaves have more prominent teeth, increasing tooth size from north to south. On the other hand, the leaves have fewer teeth, which means the number of teeth in leaves decreases as we go from north to south.