Question

A scientist studies the growth of plants in a laboratory. Which experimental procedure would provide evidence that plants need nitrogen to grow?(1 point)
Responses

Seeds are planted in two terrariums. Both terrariums are given adequate water and exposure to sunlight. A plant grows in one terrarium. The scientist measures the nitrogen content of the air.
Seeds are planted in two terrariums. Both terrariums are given adequate water and exposure to sunlight. A plant grows in one terrarium. The scientist measures the nitrogen content of the air.

Two plants are grown in pots of soil with different amounts of nitrogen. The plants have sufficient water and sunlight. The scientist measures plant growth.
Two plants are grown in pots of soil with different amounts of nitrogen. The plants have sufficient water and sunlight. The scientist measures plant growth.

Identical plants are placed in two airtight containers with sufficient exposure to sunlight. One container has nitrogen gas, and the other has room air. The scientist measures plant growth.
Identical plants are placed in two airtight containers with sufficient exposure to sunlight. One container has nitrogen gas, and the other has room air. The scientist measures plant growth.

Seeds are planted in two identical pots of soil. Both pots are given adequate water and exposure to sunlight. A plant grows in one pot. The scientist measures the nitrogen content of the soil.

Answer 1

The appropriate experimental procedure that would provide evidence that plants need nitrogen to grow is:

**Identical plants are placed in two airtight containers with sufficient exposure to sunlight. One container has nitrogen gas, and the other has room air. The scientist measures plant growth.**

This setup allows for a direct comparison of plant growth under conditions that vary specifically in nitrogen availability. One container has a controlled high concentration of nitrogen (nitrogen gas), while the other has a normal atmosphere (room air) with a lower nitrogen concentration. By measuring the growth of the plants in each container, the scientist can determine the effect of nitrogen on plant growth.