Explore Module
Brainstorming activities in the classroom
Leading question. Without light, there is no vision: what happens to light as it travels through the eye, and how does it become an electrical signal interpretable by the brain?
Prompting questions
What determines the focus of the image on the retina?
Refraction in the cornea and crystalline lens; the pupil regulates the amount of light; accommodation of the lens maintains sharpness at different distances.
Refraction in the cornea and crystalline lens; the pupil regulates the amount of light; accommodation of the lens maintains sharpness at different distances.
Why do we perceive colors poorly in the dark?
Because the activity of rods predominates (high sensitivity but no color discrimination), while cones require more light to distinguish wavelengths.
Because the activity of rods predominates (high sensitivity but no color discrimination), while cones require more light to distinguish wavelengths.
Does the retina “record” a ready-made image?
No; the retina performs pre-processing (contrast, movement, direction), then the signal travels to the thalamus and visual cortex, where information is integrated.
Why are some objects sharp at a given distance and blurred at another?
Because the focal plane depends on geometry and refractive indices; when the image plane does not coincide with the retina, the image is out of focus (myopia/hyperopia).
Because the focal plane depends on geometry and refractive indices; when the image plane does not coincide with the retina, the image is out of focus (myopia/hyperopia).
Micro-task.
Label the parts of the eye (cornea, pupil, iris, lens, retina, optic nerve) using a worksheet or an interactive resource.
Suggested resource: Labelling the Eye – Science Learning Hub
https://www.sciencelearn.org.nz/resources/3007-labelling-the-eye
Label the parts of the eye (cornea, pupil, iris, lens, retina, optic nerve) using a worksheet or an interactive resource.
Suggested resource: Labelling the Eye – Science Learning Hub
https://www.sciencelearn.org.nz/resources/3007-labelling-the-eye