Structure and Function of Bulbs, Corms and Rhizomes

6, 7, 8

Learners will recognize the structural characteristics of bulbs, corms and rhizomes. They will describe acts of philanthropy and analyze why people give to others of their time, talent and treasure.

PrintThree Forty-Minute Class Periods

The learner will:

  • observe, compare/contrast and diagram the structure of bulbs, corms and rhizomes.
  • describe how plants initiate development from bulbs, corms and rhizomes.
  • define and use the vocabulary of plant reproduction.
  • define and use the vocabulary of philanthropy.
  • define and give examples of motivations for giving.
  • Tulipmania (Handout One)
  • Paper plates, paper towels, table knives – one each per four-person lab group
  • Plant box for each group containing a daffodil and tulip bulb, crocus corm and iris rhizome and clearly labeled A, B, C and D
  • Discovery Lab Sheet (Handout Two)
  • Picture of a prominent person (Oprah Winfrey, Bill Gates, etc.) known for her/his philanthropy
  • Seven Motivations for Giving (Handout Three), for Teacher Use
  • Seven 8-1/2” by 14” inch posters, each showing one of the following:
    • Doing Good Makes Sense
    • Doing Good is God’s Will
    • Doing Good is Fun
    • Doing Good Feels Right
    • Doing Good is Good Business
    • Doing Good In Return
    • Doing Good is a Family Tradition
Home Connection 

Interactive Parent / Student Homework:Encourage learners to discuss with household members their remembrances of philanthropic acts. If the acts involve family members, they should inquire about how acts of kindness made the giver/receiver feel.



  1. Anticipatory Set:Ask the learners to close their eyes and imagine their favorite flower. Note its shape, fragrance, color and the way it makes one feel when thinking about it. Have the learners open their eyes and quickly share their thoughts.

  2. Explain how tulips have been a valuable commodity in the past, particularly during “Tulipmania” in Holland. Explain that the beauty of the flower lends itself to be a particularly welcome gift during the dreary mid-winter. Distribute Tulipmania (Handout One) and discuss how important this flower was to Dutch life and commerce. Compare the fascination with tulips to a present day phenomenon, for example, Beanie Babies.

  3. Have the learners form four-person Discovery Lab teams. Distribute Discovery Lab Sheet (Handout Two) to each student. Explain that the flower bud is ready and waiting inside the bulb, just waiting for the right combination of environmental factors to start the growth process. These tiny buds will be observed only inside the bulbs. Other differences that they should observe include the outer coverings, the eyes or growing points and the location of the root mass. The daffodil will have evident layers that are actually the leaves before emergence. They will notice that the inside and outside of their structures will have similarities as well. All structures will have solid consistencies which represent the food storage organ. The corm is actually just a swollen segment of a plant stem that stores the energy needed to grow. The rhizome is a root-like swollen stem which serves the same purpose.

  4. Preview the steps with the whole group and answer any questions about the instructions. Learners should make observations of the different structures using all the senses except for taste. These observations should be recorded in the appropriate place on their lab sheet. Cue learners to observe the differences and similarities.

  5. Learners will locate the growing tip or top of the structure. They should carefully cut each structure in half from top to bottom. Observations should be made of the cross-sections and recorded as diagrams as instructed on the lab sheet. Collect the completed lab sheets (which will be referred to at a later date when the growing plants are brought back into the room).

  6. Show a picture of a prominent person known to most of the students who is performing an act of philanthropy. Ask the learners to identify the person and to state what they think the person is doing. Be open to all answers.

  7. Ask the learners if they ever heard the word philanthropy and ask if they know what it means. Selectively write responses on the board. Define philanthropy as “individuals and organizations providing their time, talent and/or treasures intended for the common good.” Have the learners restate the definition in different ways and linking them to their initial statements on the board. Ask for examples of philanthropy from people in their community. Have the learners categorize their responses as time, talent or treasure.

  8. Show an example of the homework assignment (can be class work, if preferred). Show that it includes the student’s name, a drawing of a philanthropic act they remember in their lives (the act can be done by them or another person), and below the drawing a short description of the act. Give each student two pieces of drawing paper. Student should illustrate a philanthropic act, either their own or an act of another.

  9. Using Seven Motivations for Giving (Handout Three) as a reference, go over these seven motivations for giving. Describe each of the seven motivations and ask the learners for examples.

  10. Hang the seven “Doing Good Is...” posters on the wall, leaving some space between them. Ask each learner to explain his or her drawing. Have each learner place his or her drawing under the motivation they think best fits this act.

  11. As a review of the lesson, pair the learners. Ask “Partner A” to state something learned from the lab experience on rhizomes, corms and bulbs. Ask “Partner B” to state something learned about philanthropy and the motivations for giving. Continue for several rounds.


The completed Discovery Lab Sheet (Handout Two) may be used as an assessment of learning. The homework drawings, descriptions of philanthropic acts and partner reviews may be used as an assessment of learning.

Cross Curriculum 

None for this lesson.

Philanthropy Framework

  1. Strand PHIL.I Definitions of Philanthropy
    1. Standard DP 01. Define Philanthropy
      1. Benchmark MS.1 Define philanthropy as individuals and organizations providing their time, talent, and/or treasures intended for the common good throughout history and around the world. Give examples.
  2. Strand PHIL.III Philanthropy and the Individual
    1. Standard PI 01. Reasons for Individual Philanthropy
      1. Benchmark MS.1 Define and give examples of the motivations for giving and serving.