Question

Animals which see well during night have abundant________.
A. Rods
B. Cones
C. Scotopic cells
D. Night vision cells

Answer 1

Hint: Nocturnality is a characteristic behavior in some animals who are active at night and resting in the daytime. The common adjective nocturnal and its opposite is diurnal (used about animals and birds active during the day). In nocturnal species, there are usually well-evolved senses of sound, scent, and specially adapted eyesight.

Complete answer:
In the dusk, most nocturnal creatures have the potential to see well, making it possible for them to sneak up on unsuspecting prey. Their pupils dilate, to allow maximum light penetration into their eyes. Few animals have exceptional eyes, like raccoons, opossums, and night monkeys, to make them see better at night. Tarsiers a tiny animal has eyes larger than their brains are. At night, they can see so clearly that they can capture the tiniest creatures in absolute darkness. Carnivorous species such as red foxes, use good night vision for hunting. Some snakes also have night vision like pit viper snakes combine their vision with pits near their nostrils that sense heat to search and pray at night. Owls are one of the nocturnal bird species that use their exceptional night vision to prey. The vision of the eye occurs due to two kinds of photoreceptor cells present in the eye: rods and cones.
Rods are the photoreceptor cells that carry rhodopsin pigment and are associated with the scotopic vision of the eye i.e. vision under low light. Therefore, creatures that see well at night have higher amounts of rods in there.
Cones are the photoreceptor cells that contain iodopsin, porphyropsin, and cyan opsin pigments that are associated with daylight vision and color vision of the eyes.

Therefore the correct answer is 'Rods'.

Note: A vast number of animals, especially nocturnal, have a thick reflective membrane called the "tapetum lucidum'' meaning bright carpet. It is a layer of tissue in the eye of many vertebrate animals, which lies behind the retina. It reflects visible light through the retina, enhancing the light available to the photoreceptors. This increases visibility in the low light condition. Therefore the eyes of the animals tend to shine at night due to light reflected by the tapetum lucidum.