Question

Nitrogenfixing bacterium Rhizobiuminfects the roots of some plant species, forming a mutualism in which the bacterium provides nitrogen, and the plant provides carbohydrates. Scientists measured the 12-week growth of one such plant species (Acacia irrorata) when infected by six different Rhizobiumstrains.

(a) Graph the data. (b) Interpret your graph.

Rhizobium strain	1	2	3	4	5	6
Plant mass (g)	0.91	0.06	1.56	1.72	0.14	1.03

Short answer

(a)The data between Rhizobium strain and plant mass can be graphed by:

(b) The given data shows that at different rhizobium strains, plant mass grows differently. This means rhizobium strain affect the mass of plant differently.

Step-by-step solution

 Step 1: Mutualism

Mutualism is the type of symbiotic association in which individuals such as microorganisms and plants interact with each other, and both get a survival advantage from each of them.

One of its examples is the association of Rhizobium bacteria and plants. Rhizobium bacteria provide nitrogen compounds to the plant, and in return, the plant provides food and shelter for the bacteria to survive.

Explanation for part (a)

The data can be graphed by:

Explanation for part (b)

The given shows Rhizobium strain on X-axis and plant mass on Y-axis. The data given in the graph indicates that some of the species of Rhizobium strain (like strain 4) are beneficial for the plant, as they show a positive effect on plant mass.

Some of the species of Rhizobium strain (like strain 2) are not beneficial for the plant, as they show a negative effect on plant mass.