Question

Agrobacteriuminfects plants and causes them to form tumors. You are asked to determine how long a plant must be exposed to these bacteria to become infected. Which of the following experiments will provide the best data to address that question?

A)Measure the number of tumors formed on a plant when exposed to various concentrations of Agrobacterium.
B)Determine the survival rate of Agrobacteriumwhen exposed to different concentrations of an antibiotic.
C)Measure the number of tumors formed on plants, which are exposed to Agrobacterium for different lengths of time.
D)Measure the concentration of Agrobacteriumin different soil environments where the plants grow.

Answer 1

Answer:

Measure the number of tumors formed on plants, which are exposed to Agrobacterium for different lengths of time.

Explanation:

A scientific experiment comprises of an independent variable and a dependent variable. In the following example, the no.of tumours will be the dependent variable and the different lengths of time for which the plant will be exposed to the agrobacterium will be the independent variable.

The independent variable is the one which is changed so that its effect on the dependent variable can be studied.