Question

1. flexibility of the lens in the human eye allows the lens to

a. bend to focus the image in front of the retina
b. change shape to focus both near and distant objects
c. relax and contract to protect the retina from excess light
d. move forward or backward to control the amount of light striking the retina
hint: caution: this is a typical question in which you could answer before actually coming to the correct answer. patience. the tip is to read all the distractors all the time.

1. if the curvature along the horizontal axis of the cornea of the human eye is less than the curvature along the vertical axis, the result is.

a. nearsightedness
b. astigmatism
c. farsightedness
d. tunnel vision
hint: what is the key word in this question?

1. which is the correct description of some sensory receptors in the eye?

a. rods are concentrated near the periphery of the retina and function to detect colours.
b. cones are concentrated in the fovea of the retina and function to detect colours.
c. rods are concentrated in the fovea of the retina and function well in dim light.
d. cones are concentrated near the periphery of the retina and function well in dim light.
hint: this is logic exercise. the question writer has taken some correct concepts and scrambled them as an incorrect match with the structures rods or cones.

Explanation:

• For question 30: The flexibility of the lens in the human eye enables it to change shape to focus on both near and distant objects. Option A is incorrect as the image should be focused on the retina, not in front of it. Option C describes the function of the iris, not the lens. Option D is incorrect as the lens doesn't move forward or backward to control light amount.
• For question 31: Astigmatism occurs when the curvature of the cornea is not the same in all axes. Nearsightedness is due to the eye being too long or the refractive power being too strong. Farsightedness is due to the eye being too short or the refractive power being too weak. Tunnel vision is a loss of peripheral vision.
• For question 32: Cones are concentrated in the fovea of the retina and are responsible for color - detection. Rods are concentrated near the periphery of the retina and function well in dim light. Option A has the wrong function for rods (they don't detect colors). Option C has the wrong location for rods (they are not concentrated in the fovea). Option D has the wrong location and function for cones.

Answer:

1. B. change shape to focus both near and distant objects
2. B. astigmatism
3. B. Cones are concentrated in the fovea of the retina and function to detect colours.