The light sensitive cells in the human eye is called the ................

1. Analyze the question The question asks which part of the human eye contains the light-sensitive cells (photoreceptors).

2. Explain the concept Here is what each structure does:

• Choroid: A dark, pigmented layer rich in blood vessels. It supplies nutrients and oxygen and absorbs stray light to prevent internal reflection. It is not light-sensitive.
• Sclerotic layer (sclera): The tough, white outer coat. It protects the eye and maintains its shape.
• Retina: The innermost layer at the back of the eye. It contains the photoreceptor cells, which are the rods and cones. It is the light-sensitive layer where images are formed.
• Cones: One type of photoreceptor. They work in bright light and detect colour. They are only part of the light-sensitive cells, not the whole group.

3. Solution

• The question says "light sensitive cells" (plural, as a general group) in the human eye.
• Rods and cones are both light-sensitive cells, so "cones" alone is incomplete.
• The structure that holds all of these light-sensitive cells is the retina.
• Choroid and sclera do not detect light.

4. Answer C. Retina

5. Exam tip Remember the eye layers from outside to inside: S-C-R (Sclera → Choroid → Retina). Only the innermost layer, the Retina, "Receives" light. Also, if the options include both a whole structure (retina) and one of its parts (cones), check the wording. A general phrase like "light-sensitive layer or cells" points to the retina, while "colour vision in bright light" points to cones.