Teaching overview
Learning points
- Bees are pollinators, which means they transfer pollen between flowers.
- Bees and other insects pollinate around a third of our food crops, so recent declines in population size are cause for concern.
- One possible threat to honeybees is the use of certain types of pesticide.
- There is evidence that some pesticides can cause bees to become forgetful and confused, making it harder for them to return to their hives with food.
Curriculum keywords
- Animals
- Life cycles
- Reproduction
Spark a discussion
- How do plants reproduce?
- Why are bees and other insects important for plant reproduction?
- What is pollination?
- What is a pollinator? Can you name some pollinators?
- How can insects damage plants? Why might this be a problem?
- What can people do to stop insects damaging plants?
- What are pesticides? How do they work?
- How might pesticides harm bees?
- What are the arguments for and against using pesticides to protect food crops?
- What else might be causing bee populations to decline?
- Why does Professor Randolf Menzel track honey bees? What does he find out?
- Why is it important to protect bees?
- How could a decline in the number of bees affect food production?
Multimedia toolbox
Bees audio loop
Play the audio loop as the students enter the classroom to spark a discussion about why bees are important to humans and other living things.
Pollinators
Show the visual before the video and ask the students what they think these animals are doing, and why.
Parts of a flower (unlabeled) diagram
Show the visual before or after the video and challenge the students to label the parts of a flower.
Parts of a flower (labeled) diagram
Show the visual before or after the video. Ask the students to research the role of each part and describe what happens during pollination.
Pollination
The process by which pollen is transferred from an anther to a stigma of a flower.
Pollination
Show this visual after the video to reinforce key scientific language.
Activities
Demonstrating pollination
DEMONSTRATE how bees collect pollen as they feed on plant nectar.
Other activity ideas
- MAKE a poster showing the life cycle of a flowering plant and the role that bees and other insects play in the pollination process.
- OBSERVE flowers under magnifying lenses, then dismantle the flowers carefully and look closely at the structures inside.
- RESEARCH and present information on different flowers found in the local area, particularly those that are wind-pollinated or pollinated by animals.
- MAKE a bee watering station by placing marbles or rocks in a container and adding water. The marbles or rocks give the bees somewhere safe to stand while drinking.
Demonstrating pollination
Duration: 60 minutes
Resources:
- 2 squares of brightly colored felt
- Black marker pen
- Scissors
- 2 straight straws
- 2 plastic cups
- Water
- Confectioner's sugar
- Hole punch
- Scotch tape
Key Learning:
This activity gives students the opportunity to develop their scientific vocabulary of the reproduction parts of plants, by demonstrating how bees transfer pollen from flower to flower as they drink nectar.
Activity preparation: To save time, you may wish to draw the flower outlines and make the holes before the lesson. This means that the students only have to cut out the flowers.
Activity instructions:
- Discuss with the class what they know about plant reproduction and pollination. You can ask the following prompt questions:
- How do flowering plants reproduce?
- What are the reproductive parts of a plant called?
- Why do bees visit flowering plants?
- What role do bees play in pollination?
- Can you describe the pollination process?
- Organize the class into pairs and distribute the resources.
- Ask the pairs to carry out the following instructions:
- Use the marker pen to draw two identical flowers with six petals onto the squares of felt.
- Use a hole punch to make a hole in the middle of each flower. Note: The students may need your help with this.
- Cut out the two flowers.
- Gently push the straws through the holes in the flowers, leaving a 1.5–2 cm length sticking out the top of each one. Use Scotch tape to secure the straws below the flowers.
- Draw a circle around the straw on one of the flowers. This represents an anther. Mark a zigzaggy circle around the straw on the other flower. This represents a stigma.
- Sprinkle some confectioner's sugar inside the circle of the first flower.
- Half fill the plastic cups with water.
- Place the “stems” of the flowers in the water.
- Ask the students the following questions:
- What does the circle on the first flower represent? The anther.
- What does the confectioner's sugar represent? Pollen grains.
- Why are the flowers brightly colored? To attract pollinators.
- What does the water represent? Nectar.
- What does the zigzaggy circle on the second flower represent? The stigma.
- What does the straw underneath each flower represent? The stem.
- What do bees drink and how do they collect this? Bees drink nectar and they collect this by visiting lots of flowers.
- Tell the students that they are going to pretend to be bees. To do this they will take a sip of nectar from the first flower (the one with the confectioner's sugar) and then take a sip from the second flower. Ask the students to make a prediction about what will happen when they drink nectar from the flower with pollen on top.
- Listen to the students’ suggestions and then ask the pairs to carry out the demonstration. Tell the pairs that they should take turns at doing this.
- Discuss the students’ observations and how these relate to the real-life process of pollination. You can ask the following questions:
- What happened when you drank nectar from the flower that had pollen grains on top? The pollen stuck to my face.
- What happened as you drank nectar from the second flower? The pollen grains were transferred from my face to the flower.
- What happens when bees drink nectar from real flowers? Pollen grains from the anther of one flower stick to the bees as they drink, and are then transferred to the stigma of another flower.
- Ask the students to write a paragraph and draw pictures to explain the process of pollination, referencing their experiences from the demonstration.
Background information
- Pollination is when pollen is transported from the male anthers to the female stigma. There are two types of pollination: self-pollination (when pollen is transferred to the stigma of the same flower, or another flower on the same plant) and cross-pollination (when pollen is transferred to the flower of a different plant).
- One of the most common methods of cross-pollination uses animals known as pollinators. Brightly colored and strongly scented flowers encourage animals to visit the plant, where they consume a sugary substance called nectar. While the pollinator feeds, pollen is transferred from the flower’s anthers to the body of the animal. When the animal then visits another flower in search of more nectar, the pollen is transferred to the second flower’s stigma.
- All living things depend on other species for their survival. This is known as interdependence. The mutually beneficial relationship between flowering plants and bees is one example of interdependence. Lots of flowering plants rely on bees to transfer pollen and the bees rely on plant nectar as a source of food. If the populations of either the bees or the flowering plants were to decline, the other would be negatively impacted.
- Bees play an important role in our food chain. Around a third of the food we eat depends on bees and other pollinators in some way. But millions of honey bees are dying every year and scientists are trying to find out why.
Glossary
- Pollination
- The process by which pollen is transferred from an anther to a stigma of a flower.
- Pollinator
- An animal that pollinates plants by carrying pollen from one flower to another.
- Pesticide
- Any substance that is intended to kill or repel pests, particularly through the use of chemicals.
Twig Science: A Complete Pre-K–8 Program for the NGSS
Immersive Investigations with High-Quality Multimedia
- Investigating, designing, building, and understanding phenomena
- Hands-on, digital, video, and print investigations
- Synchronous/asynchronous distance learning