Explore - What do stems do?

The stems of a plant are often the part of a plant that we use as food sources.  The stem of a plant contains xylem and phloem tissues within it.  You learned in previous activities that food items such as asparagus, rhubarb, and celery are the stems of plants.  Look a bit closer at the purpose of a stem of plant.

Skill Builder

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 Notebook: What is the purpose of the stem of a plant?

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  2. Complete the activity and check your answers below.
  3. Save your corrected work to your Plant Notebook.

 Check Your Answers

Conclusion Answer


The purpose of the stem of a plant is to allow water to travel through it. I know this because the colour in the water changed the colour of the celery leaves. The water travelled up the stem to the celery leaves. The food colouring moved through the stem allowing the colour to be taken to the celery leaves to cause their colour to change. The celery stalk pulled the dyed water up through its stem and into the leaves.

How does this happen?


The stem is the main supportive part of the plant that holds the leaves to the sun so that they can photosynthesize food. Because it is also the connection between the leaves and the root system where water and minerals are absorbed, it is also part of the plant’s transport system. The stem contains two types of tubes for transport:

  1. xylem tubules that transports water and minerals from the soil to the rest of the plant

  2. phloem that transports food produced in the leaves to other parts of the plant

The celery should turn the same colour as the food colouring because the water and the food colouring are absorbed by the roots and transported through the xylem, up the stem, and to the celery leaves.

Career  Connection


Video

The development of various colours of commercial flowers such as carnations and unique roses use the concept you studied in the last activity.

Investigate these rainbow roses...

...and these coloured carnations.

To make the rainbow flowers, a process similar to that seen in the carnation video is used, but the stem is sliced into more sections. Fascinating!