Bee pheromone molecules

Students smell bottles containing bee pheromone (signalling) molecules. They smell like bananas, lemon, blue cheese, fruit or nothing to us. Students match the molecule pictures to discover what each smell means to a bee.
Science content
Biology: Features, Adaptations of Living Things (K, 1, 3, 7)
Biology: Sensing, Organ Systems (4, 5, 6)
Chemistry: Atoms, Molecules (3-7)
Lessons activity is in
  • 4 Squeeze Smell Bottles containing the different smells:
  • few drops lemon essence, containing the molecule citral
  • gorgonzola or other stinky cheese wrapped in tissue, containing the molecule 2-heptanone (heptan-2-one)
  • few drops banana essence, containing the molecule isoamyl acetate (isopentyl acetate)
  • (one bottle is empty)

Bees can talk to each other with smelly molecules, called pheromones.

Students squeeze and sniff each of the bottles. Ask them what the smell makes them think of. (Likely lemon, banana, cheese and nothing.)

When a bee smells these same molecules it thinks of something quite different. Students match the molecule labels on each bottle with the molecules on the sheet to find out what each of these molecules means to a bee:
This might smell like bananas to you (banana smell), but to a bee it means war. This molecule signals bees to attack an intruder.
This molecule says it's moving day to a bee (lemon smell). Bees smelling this molecule swarm and move to a new hive
Feel alarmed when you smell this? A bee would (cheesy smell). Guard bees release this molecule to call for help when there is an intruder.
Although we humans can't smell this molecule (oxodecanoic acid, so use empty bottle), it is a perfume for bees. Queen bees release this molecule to attract males.

It may seem strange that other animals communicate with smell molecules. We mostly use our other senses to communicate.
Many creatures communicate with smell molecules.Dogs use smell molecules to mark territories. Ants leave pheromone molecules for each other to show the way to food.

Attached documents
Grades taught
Gr K
Gr 1
Gr 2
Gr 3
Gr 4
Gr 5
Gr 6
Gr 7