Question

The eyes of tigers and wolves shine (reflect back the light focused on them) because
A. Cornea is opaque
B. Retina does not have enough rods.
C. Retina has only rods and cones.
D. None of the above

Answer 1

Hint:
Some animals’ eyes like tigers, wolves, etc shine in the night-time mainly due to the specialized eye structure. A layer is present at the back of the retina in this animal that reflects back the light and makes the eyes shine at night.

Complete answer:
The eyes of tigers and wolves etc glow at night because they have a specialized type of reflective layer behind the retina of their eyes. The refractive layer is known as tapetum lucidum which enhances the amount of light absorbed by the photoreceptor in their eyes and makes the eyes of animals look glowing in the dark.
Tapetum lucidum is a membranous layer that is present in vertebrates as well as invertebrates. The main function of the tapetum lucidum is to increase the light available to the photoreceptors in the eyes. Photoreceptors are rods and cons which are specialized neurons. These photoreceptors are associated with the vision of the eyes. Rods are accountable for vision at low light levels while cones are accountable for vision at a higher level of light
Tapetum lucidum has its own colour but eyeshine shows a luminous colour that seems to change when seen from different angles. Blue periphery, greenish, golden, or yellow is some of the common colour of the animals that we see in animals in dark.
Hence the correct answer is None of the above.

Option ‘D’ is correct

Note:
Human eyes lack tapetum lucidum behind the retina. That is the reason our eyes do not shine in the dark.