Investigating the Structure of the Flower

Charles Buzek John Spry School
2300 S. Marshall
Chicago IL 60623
(773) 534-1400


The student will learn the basic anatomy of a flower by means of creating a
The student will understand the proportional relationships of the various
parts illustrated.
The student will understand the value of modeling for learning purposes.

Materials Needed:

Two sticks of clay
Two sheets of construction paper-red and green


Though flowers come in many varieties there are types that have both male
and female sex organs on the same flower. These types are called perfect
flowers. We can construct a model of a perfect flower with the above-mentioned
materials. We start with a stick of clay which we use to fashion the stem. The
stem will need to support the flower itself and will therefore need to be strong
enough to support the structure. So don't stint on the amount of clay, use the
entire stick to make the stem. Once done we need to cut out the sepals from the
green paper. The sepals were the bud cover while the flower was developing.
When the flower opened the sepals are pushed back and begin to shrink since they
no longer function as part of the living flower. The sepals should be no larger
than one-fourth the size that the petals will be for your model. Start by
drawing a circle the size of the stem, this will be cut-out later. Around this
circle draw a four-pointed star. This forms the sepals and when the circle is
cut out it will fit over the top of the clay stem. Push the sepals down about
one-half inch on the stem.
Now cut out from the red sheet the figure which will represent the petals of
your flower. Again, as mentioned above, the petals need to be larger than the
sepals. The ratio should be about 4 to 1. The petals serve as a type of
container for the sexual organs of the plant, attractant of insects, and landing
strip for the insects. The number of petals is specific for each floral genus
so you are free to decide how many petals you want. As in the case of the
sepals you must start with a circle the size of the stem. Once the petals are
cut out, followed by the circle, fit them over the stem so that they rest on top
of the sepals leaving a knob of clay.
The knob of clay will serve as a platform for the structures that we will
now fashion. These structures are the stamen and the pistil. Beginning with
the latter we will knead the clay into a shape that resembles a bowling pin.
Since we are emphasizing these features they may be slightly exaggerated in
size. Thus the pistil may be the size of your petals. The shape of the pistil
is a case of form following function. The top portion of the structure is a
landing platform for pollen. The enlarged base contains the ovules that sperm
from the pollen will eventually fertilize.
Since nature usually prefers to avoid self-pollination the next structure,
the stamen, should be modeled smaller in size than the pistil. It consists of
the anther, which is the production site of the pollen, and its support, the
filament. The latter is made with a toothpick, though for large-scaled models a
drinking straw may be used. The anther should be a third to half the size of
the filament. Its shape is much like an elongated kidney bean. The stamen
should be grouped around the pistil, a suggested number could be six.

Performance Assessment:

Any type of modeling activity requires a high degree of concentration and a
considerable return on the effort is a reasonable expectation. Consequently
students can be tested on their acquired knowledge by having them make a drawing
of a flower based entirely on memory. The drawing should be correctly labelled.
One might give a possible number of five quality points based on their drawing
and nine points for the flower parts for a total of fourteen points.

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