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{{U}} (31) {{/U}}with the human eye, a cat’s{{U}}
(32) {{/U}}have more rods than cones,{{U}} (33) {{/U}}helps
the cat see in the dark. Cats also have elliptical pupils that open and close
faster and can become larger than our round{{U}} (34) {{/U}}. In
addition, cats and some{{U}} (35) {{/U}}nocturnal animals have a mirror
like membrane on the back of their eyes, which reflects the light passing
through the rods back through them in the, opposite direction, This "double
exposure" allows cats to{{U}} (36) {{/U}}well in near
darkness.
The human eye changes gradually{{U}} (37)
{{/U}}age,{{U}} (38) {{/U}}the changes are critical. In darkness,
eyes adapt{{U}} (39) {{/U}}widening the pupils to let in as much light
as possible. {{U}} (40) {{/U}}you get older, these muscles weaken and do
not respond as well{{U}} (41) {{/U}}the need to let in more
light.
The result is a small{{U}} (42) {{/U}}when you
try to see in poor
