Assignment - Infographics - 132

A Note on What Makes This an Infographic

An eye cross-section with labeled parts - cornea, iris, lens, retina - is a diagram. An infographic about the eye explains what actually happens to light as it passes through each structure, why each part is shaped the way it is, and why you see a sharp, full-color image despite the fact that the image on your retina is upside down and inverted. Your infographic should leave a reader understanding how sight works, not just what the parts are called.

Objective

Create a journey narrative infographic in Canva that follows light from the moment it enters the eye to the moment the brain produces a visual image, explaining the role of each structure and how the eye creates focus.

The Journey to Follow

Structure your infographic as a numbered journey:

Stage 1: The Cornea Light first hits the cornea - the transparent, curved outer surface of the eye. The cornea does approximately 70% of the eye’s total focusing work, bending (refracting) light inward. Because it is fixed in shape, it cannot adjust focus. That job belongs to the lens.

Stage 2: The Aqueous Humor Light passes through a clear fluid called the aqueous humor, which fills the space between the cornea and the lens. It maintains the eye’s shape and provides nutrients to the cornea and lens (which have no blood supply).

Stage 3: The Iris and Pupil The iris is the colored part of the eye. It controls the size of the pupil - the opening at its center. In bright light, the iris contracts to make the pupil smaller, reducing the amount of light entering. In dim light, the iris dilates to make the pupil larger. This is the eye’s automatic exposure control.

Stage 4: The Lens The lens fine-tunes the focus that the cornea began. Unlike the cornea, the lens can change shape. Muscles attached to it (ciliary muscles) squeeze it to make it more curved for close objects, or flatten it for distant objects. This adjustment is called accommodation.

Stage 5: The Vitreous Humor After the lens, light passes through a clear, jelly-like substance that fills most of the eye’s interior. It maintains the eye’s spherical shape.

Stage 6: The Retina Light lands on the retina - a layer of light-sensitive cells lining the back of the eye. The retina contains two types of photoreceptor cells:

• Cones (approximately 6 million): concentrated at the fovea (center of the retina); detect color; work in bright light.
• Rods (approximately 120 million): spread across the retina; detect light and dark; work in dim light; responsible for peripheral vision.

The image formed on the retina is inverted (upside down) and smaller than the real object.

Stage 7: The Optic Nerve Photoreceptors convert light into electrical signals. These signals travel along the optic nerve to the brain. The point where the optic nerve leaves the retina has no photoreceptors - this is the blind spot.

Stage 8: The Brain (Visual Cortex) The visual cortex at the back of the brain processes the electrical signals and produces the final image - right-side up, in color, and in three dimensions (by combining images from both eyes). The brain corrects the inversion the eye creates.

Design in Canva

• Show the eye in cross-section in the center of your infographic.
• Number each stage with arrows showing the path of light.
• Each stage gets a labeled callout with the structure’s name, its action, and one fact that makes its role clear.
• Include a small panel showing the inverted image on the retina and how the brain corrects it.
• Use amber/warm tones for the path of light, cooler tones for neural processing stages.

Required Elements

• All 8 stages in correct order, each with a function explained.
• The cornea vs. lens roles clearly distinguished (fixed focus vs. adjustable focus).
• Rods vs. cones explained with numbers.
• The inverted retinal image and brain correction noted.
• The blind spot mentioned.
• Title: “How the Eye Works: The Journey of Light.”