September 2, 2020
Dissect a flower to understand how they reproduce
Spring is here and the flowers are in bloom. Flowering plants, also known as angiosperms, are seed-producing plants and are considered the most diverse of all the land plants. Angiosperms are vascular, meaning they have tissues that transport water and nutrients throughout the plant.
In this activity, you’ll follow along in dissecting a flower while learning all about flowers and the role they play in the reproduction of plants.
It will take about 10-15 minutes to prepare for the activity and about 15 minutes in learning time. This activity is best suited for students in elementary or middle school.
All you need for this activity is an interesting flower, a steady hand and a healthy dose of curiosity. A magnifying glass and a sharp pair of scissors are helpful, too.
Irises, lilies like alstroemeria or any flower with generally large parts will work well for this activity. Feel free to look around your yard or neighborhood for the right flower. Just be sure to ask permission before you pluck one! (You might also ask an adult at your home to grab one from the floral department of the grocery store during an upcoming visit.)
- Pick the perfect flower. Look at your flower specimen up close, taking note of the main parts of the flower. A perfect flower is one with both female and male parts. The male portion of the flower is called the stamen and is broken down into two parts: anther and filament. The female portion of the flower is called the pistil and is broken down into four parts: the stigma, style, ovule and ovary.
- Remove the petals. Carefully remove each petal of your flower, pulling them down toward the stem. How many petals does your flower have? Like all life on Earth, flowering plants are incredibly diverse. You can tell a lot about them just by looking at the number and orientation of the petals. While examining your specimen, look to see if your petals are arranged in multiples of three, which indicates it is a monocot, or multiples of four or five, indicating the flower is dicot. Flowering plants are either monocots or dicots. Monocots have just one cotyledon (embryonic leaf that is the first to appear from a seed) while dicots have two cotyledons.
- Remove the stamen. The long stalk of the stamen is called the filament. At the top of the filament is the anther, which holds the pollen. Once you’ve carefully removed each stamen, separate the anther from the filament. Pollen is more than an annoying allergen; this powdery dust is produced by trees, weeds, grasses and flowering plants and it helps fertilize and grow more of them.
- Cut the pistil in half lengthwise. Using a sharp knife or a pair of scissors, carefully cut the pistil in half lengthwise to reveal the hollow tube within the style. The top of the pistil is the stigma, which collects the pollen and carries it through the style, a hollow body, to the ovary. The ovary is where the pollen fertilizes the flower’s eggs.
- Observe. Now that you’ve successfully dissected your flower, observe its parts and pieces. If you happen to have a magnifying glass or microscope at home, take an even closer at your plant specimen. Draw what you see.
How to adjust for younger and older learners
For younger learners, encourage them to begin their flower dissection by identifying the leaves and stem of their flower. The stem of the flower plays an important role in providing stability for the plant. The leaves are the sight where gas exchange takes place and photosynthesis. Plants are producers, meaning they use light energy and convert it to sugar, which feeds the plant. Encourage your young ones to draw their plant and identify the parts they learned about.
For older learners, dissect multiple flowers of both the same and different species. After dissecting, lay out the petals of the chosen flowers to observe any differences or similarities between them. The veins on the leaves of a monocot are typically parallel while the dicots resemble a net or web-like pattern. Additionally, use the leaf shape, number and orientation of petals to identify whether or not their selected flowers are monocots or dicots.