Question

write the difference between
1) rods and cones
2)
Blind spot and fellow spot.​

Answer 1

Answer:

Hello mate

Explanation:

1. Rods and cones :-

Rods are responsible for vision at low light levels (scotopic vision). They do not mediate color vision, and have a low spatial acuity. Cones are active at higher light levels (photopic vision), are capable of color vision and are responsible for high spatial acuity. The central fovea is populated exclusively by cones.

2. Blind spot and fellow spot :-

The spot at the back of the eye, from where optic nerve fibres leave is free from rods and cones. This spot is devoid of the ability for vision and is called blind spot. Yellow spot or area centralis or Macula lutea is in the exact centre of the retina.

Answer 2

Answer

(1) Difference between rods and cones :

$\bigstar$ Rods :

• Rods help in twilight vision.
• Rods are the photoreceptor cells of retina that are sensitive to dim light.
• They have visual purple pigment called rhodopsin.

$\bigstar$ Cones :

• Cones help in colour vision.
• Cones are the photoreceptor cells of the retina that are sensitive to bright light.
• They have visual violet pigment called iodopsin.

(2) Difference between Blind spot and yellow spot :

$\bigstar$ Blind spot :

• It is a blind spot on the retina present at the point of origin of the optic nerve.
• They are insensitive to light as both rods and cones are absent.
• Photoreceptor cells are absent from this region.

$\bigstar$ Yellow spot :

• yellow spot is a small area on the retina present at the posterior part of the eye.
• They are sensitive to bright light as cones are present.
• Only cones are present in this region.