Plant Growth and Development

Lesson Summary At this time the plant will start to develop its first true leaves and flower buds.  Students continue measuring and graphing their selected plant’s height, along with observing and recording the height and changes in all of the plants. Teacher Background The plant is now growing its true leaves.  The seed leaves (cotyledons from inside the seed) produced food for the young seedling, but as the true leaves develop, they now take on this important job.  The true leaves differ from the seed leaves in their shape, size and number.  The true leaves have jagged edges, start out quite small but generally grow to be much larger than seed leaves, and have an undetermined number on each plant.  While the plant only has 2 seed leaves, it continues to produce more true leaves until it is near the end of its life cycle.  The seed leaves eventually turn yellow, wilt, and drop off. Set-up/Management Tips Visit the Wisconsin Fast Plants website: www.fastplants.org/intro.lifecycle.php#menu (Life cycle pictures) www.fastplants.org/grow.tending.php#menu (Troubleshooting for growth problems) A flex cam is a good piece of technology to use with this lesson to show detail. The flowers of the Brassica plant do produce pollen. You will want to be aware of this fact and inform parents of any students with severe pollen allergies ahead of time. Literacy Support Scientific Vocabulary The following words are key vocabulary words that will be introduced in this lesson and reinforced throughout the unit: flower flower buds