🔬 Group A
Phase 3 — Investigation
🧬 Interactive
⏱ 15 minutes
Task 4 — The Scientist
Investigate how rods, cones, trichromacy and colour blindness work. Use AI to research, build an annotated infographic, and fact-check one claim against a trusted source.
Step 1 — Read before you start
Group A — How the Eye Really Works
Read or listen to this before the interactive tools unlock
Inside the retina are two main types of photoreceptor cells: rods and cones.
Rods are very sensitive to light and help us see in dim conditions — but they do not detect colour. You have about 120 million rod cells in each eye.
Cones work best in brighter light and help us distinguish colours. Humans usually have three types of cones: S-cones (blue), M-cones (green) and L-cones (red). Each type is most sensitive to a different range of wavelengths.
The brain compares signals from all three cone types simultaneously — like mixing three spotlights — to produce the full range of colours we see. This is called trichromacy.
🔎 Fact-check reminder: As you explore, check whether AI correctly explains rods, cones and trichromatic colour vision. Do not accept a statement until you compare it with a trusted source.
Rods are very sensitive to light and help us see in dim conditions — but they do not detect colour. You have about 120 million rod cells in each eye.
Cones work best in brighter light and help us distinguish colours. Humans usually have three types of cones: S-cones (blue), M-cones (green) and L-cones (red). Each type is most sensitive to a different range of wavelengths.
The brain compares signals from all three cone types simultaneously — like mixing three spotlights — to produce the full range of colours we see. This is called trichromacy.
🔎 Fact-check reminder: As you explore, check whether AI correctly explains rods, cones and trichromatic colour vision. Do not accept a statement until you compare it with a trusted source.
retina
rod
cone
wavelength
trichromacy
Step 2 — Interactive Retina Diagram
👁 Click a cell to explore how it responds
Select rod cells (grey) or cone cells (coloured) in the diagram
Overview
🔘 Rods
🔴 L-Cone
🟢 M-Cone
🔵 S-Cone
Click a cell to explore
Select any rod or cone cell in the diagram on the left, or use the tabs above. Each cell type plays a different role in how you see colour and light.
Step 3 — Colour Blindness Simulator
👁 Simulate different types of colour vision
Drag the slider or tap a type to see how someone with that condition experiences colours side by side
Normal Vision
Deuteranopia
Protanopia
Tritanopia
Normal vision
Simulated view
This is how most people see. About 8% of men and 0.5% of women have some form of colour vision deficiency. All three cone types (L, M, S) are working normally.
Step 4 — AI Research & Fact Check
🤖 Wonder Learning AI — Group A
Generate an AI explanation, highlight one sentence, then fact-check it against a trusted source
Pre-loaded prompt (editable)
"Explain trichromatic colour vision to a 13-year-old. Include one surprising fact about colour blindness."
🔍 Fact-check this statement
Select a sentence above to fact-check it.
Verify against a trusted source:
Khan Academy — Trichromacy
Wikipedia — Cone cell
BBC Bitesize — The Eye
My verdict:
✅ Fact-check saved to your portfolio!
Bridge to Phase 4
"You have investigated how the eye detects colour at a biological level. When you present in Task 9, explain the one thing that surprised you most — and the one AI claim you verified."
What happens in Task 4
Group A investigates the biological mechanism of colour vision. After reading the intro content (and tapping "Mark as understood"), students explore an interactive retina diagram showing how rod and cone cells respond to light, use a colour blindness simulator with side-by-side normal and simulated views, generate an AI explanation, highlight one sentence, and fact-check it against three pre-curated sources. A mid-investigation quiz auto-triggers at 10 minutes for all groups simultaneously.
📋 Learning objectives
- Understand the biological mechanism of colour detection in the human eye
- Identify the difference between rod and cone cells and their functions
- Use AI tools critically — generating content and verifying it against a trusted source
🔑 Key terms
retina
rod
cone
wavelength
trichromacy
deuteranopia
protanopia
♿ SEN Adaptations
- All workspace text has read-aloud (speaker icon on every text block)
- Simplified AI response mode toggle — button labelled "Simpler please" below AI response
- Output builder supports voice labels and hand-drawn content (photograph and upload)
- No minimum output requirement — process engagement is assessed, not volume
- Retina diagram cells have keyboard navigation and screen-reader labels
- Colour blindness simulator includes text descriptions of each condition
🖨️ No-Tech Format
- Printed investigation card with guided question list
- Printed retina diagram to annotate by hand
- Two printed source article excerpts (Khan Academy + BBC Bitesize)
- Blank output template for drawing and labelling
- Teacher reads AI responses aloud and discusses as a group
🔬 Extension (ages 13–15)
- Research tetrachromacy — some humans have a 4th cone type. What colours might they see?
- Compare colour vision across species: mantis shrimp (16 photoreceptors), dogs (2), mantis shrimp vs human
- Explore how wavelength values (nm) map to the full response curves of S, M and L cones