Some students are instructed to put a celery stalk in a red dye solution for a lab activity. First the students carefully cut the bottom of the stalk with a scalpel. Then they put the stalk in the beaker with the solution and place the beaker on a shelf in the lab room. The next day they check the stalk and make observations. The students note that the leaves at the end of the stalk have changed color from green to red. The students cut across the celery stalk and use a hand lens to see that the small tube openings along the edge of the celery stalk are also red. The cross section is shown below. How do the plant systems work together to make this movement of liquid possible?

An animal can wound a tree by scratching away the bark. The tree can respond to the wound in many ways. Usually sap quickly covers the wound, and then the tree covers the wound with new growth. The diagram shows a cross section of a tree with a healed wound. What process worked most directly with the transport system to heal the wound?

Structures represented in the illustration below are found in the lower epidermis of a plant leaf. The illustration at right shows the response to a certain environmental condition. The response represented in the illustration would most likely be caused by -

The diagram shows the reproductive system of a plant. Which of the following best describes the interaction that occurs between a plant's reproductive parts during self-fertilization?

Several structures work together to allow flowering plants to reproduce. The diagram shows a typical flower. Which table correctly identifies the function of each structure or group of structures in the reproduction of the plant?

A student reads this advertisement for a product containing a plant micronutrient that can be added to soil. Based on this information, the student can conclude that boron is absorbed by plant roots from soil and then -

A student conducted an investigation to study phototropism in grasses. The only difference between the control group and the experimental group was light conditions. The control group was provided full light, while the experimental group was shaded on one side. The diagrams show the average heights and positions of blades of grass in the investigation. Which statement best explains why the grass tips of the experimental group bent toward the light?

Plant roots have extensions called root hairs. These root hairs are important in the homeostasis of the plant. Which statement best explains the importance of the root hairs to the stems and leaves of the plant?

A corn plant produces both male and female flowers. The male flower forms the tassel and the female flower forms the ear of corn. The silks that emerge from the ear are the stigma of the female flower. Each silk leads to an ovule that can become a corn seed. Which of these must happen for corn seeds to develop on the ear?