Science (EVS K-5) · Class 7

Active learning ideas

Fertilisation: From Pollen to Zygote

We know how pollen makes its journey from one flower to another, but what magical process happens inside the flower to create a seed?

• CBSE Learning Outcomes
• NCERT Class 7 Science: Chapter 12 - Reproduction in Plants

• 15–30 min
• Pairs → Whole Class
• 3 activities

Activity 01

• Simulation Game
• 25 min · Small Groups

Pollen Tube Journey Model

Students use chart paper to draw a large cross-section of a pistil. They then use a string to represent the pollen tube, guiding it from a paper pollen grain on the stigma down to a bead representing the ovule.

Explain the process of fertilisation in a flowering plant.

Facilitation Tip

Provide different coloured strings and beads to represent the male gamete, pollen tube, and ovule for clarity.

What to look for

Ask students to draw a flowchart showing the sequence of events from pollination to fruit formation.

• Apply
• Analyze
• Evaluate
• Create
• Social Awareness
• Decision-Making

Activity 02

• Simulation Game
• 30 min · Pairs

Dissect a Hibiscus Flower

Provide students with a common local flower like a hibiscus (gurhal). Guide them to carefully remove the petals and stamens to expose the pistil, then make a careful incision in the ovary to observe the small ovules inside with a magnifying glass.

Identify the parts of the flower that develop into the fruit and the seed.

Facilitation Tip

Remind students to be gentle and use a blade or forceps only under strict supervision.

What to look for

A short test with a diagram of a pistil showing fertilisation. Students must label the pollen tube, zygote, and ovule, and answer questions about post-fertilisation changes.

• Apply
• Analyze
• Evaluate
• Create
• Social Awareness
• Decision-Making

Activity 03

• Simulation Game
• 15 min · Small Groups

From Flower to Fruit Sorting

Create cards with images of flowers (e.g., tomato, brinjal, mango) and their corresponding fruits. Students work in groups to match the flower to the fruit and identify the part of the flower that developed into the fruit.

Analyse the journey of the male gamete from the stigma to the ovule.

Facilitation Tip

Include a 'trick' card, like a carrot or potato, to spark a discussion on which plant parts we eat.

What to look for

Provide a checklist with 'I can' statements, such as 'I can explain the role of the pollen tube' or 'I can tell the difference between an ovary and an ovule'.

• Apply
• Analyze
• Evaluate
• Create
• Social Awareness
• Decision-Making

A few notes on teaching this unit

Begin by recapping the parts of the pistil. Use a large, clear diagram or a 3D model to trace the path from stigma to ovule. Use an analogy like a courier service: the pollen grain is the package, the pollen tube is the delivery route, and the male gamete is the precious item inside. This helps separate the components of the process clearly for students.

Through these activities, your students will be able to visualise the hidden journey of the male gamete and explain exactly how a flower transforms into a fruit.

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Watch Out for These Misconceptions

• Pollination is the same thing as fertilisation.

  Pollination is only the first step, where pollen is transferred to the stigma. Fertilisation is the next, separate step where the male and female gametes actually fuse inside the ovule.

• The entire pollen grain travels down to the ovule.

  The pollen grain itself stays on the stigma. It grows a very thin tube, called the pollen tube, which travels down the style to deliver the male gamete to the ovule.

• All parts of the flower, like petals, grow into the fruit.

  After fertilisation, parts like petals, sepals, and stamens usually wither and fall off. Only the ovary develops into the fruit, and the ovules inside it become the seeds.

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Methods used in this brief

• Simulation Game