How does a flower become a fruit?
Fast fact: Most flowering plants rely on pollinators for survival. Did you know that one out of every three bites of food we eat is made possible by pollinators?
Pose the focus question
As a class, brainstorm the answers to the focus question. List further key words and questions as they arise.
If you get stuck, try answering the following questions.
- Why do all fruits have seeds?
- Do all flowers become fruits?
- Do all plants have flowers?
Articulate and record all vocabulary arising from discussion. Create a concept map.
Present a large flower to the class e.g. Tiger Lily, sunflower, strawberry or whatever you can find. Identify and label the flower parts using the General flower anatomy diagram. List other flowers known to students and discuss whether any of these become edible.
Move out to the school garden or go on a short excursion to a nursery. Ask students to photograph or sketch the flowers and match them to the resulting fruit (if they know them). Create a matrix of knowledge of plants, flowers, seeds and fruit using the Plant and insect matrix.
When you are back in the class, discuss the purpose of flowers. If flowers contain the reproductive part of the plant, what is their role?
Without a transfer of pollen from the anthers to the stigma no fruit, and subsequently no seed, would develop. Ask your students to get into pairs and hypothesise why they think flower shapes different.
Investigate the seed to fruit cycle using Plant life cycle and processes and by dissecting a fruit or vegetable e.g. capsicum, pumpkin, tomato. You may need to dry out seeds to sow at a later date.
For a longer class project, grow a radish (radish grow from seed to edible tuber in about six weeks) and follow its progress.
Discuss the following questions as a class.
- Why are the flowers different shapes?
- Can we pollinate a flower?
- Do all plants flower at the same time?
Pollinate a flower using your fingers and observe some pollen grains under a microscope or digi-cam. If you have them available, a lily is a useful flower for this as the pollen grains are large and colourful.
Check in with your students on if they now believe flowers and fruits are essential reproductive parts of a plant. As a class, discuss what you think insects receive from a flower.
- Flowers contain the reproductive parts of a plant. Their purpose is to allow pollination to take place. Pollination involves transfer of pollen from the anthers to the stigma.
- The fertilized embryo develops in to a seed and the surrounding tissue often develops into what we know as a fruit.