Retina

Q.

Where is the visual acuity greatest in the eye?

Q. Scotopsin is the component of

1. cones
2. iodopsin
3. rhodopsin
4. vitamin K

Q. Which cells directly transmit action potentials to the optic nerve?

1. bipolar cells
2. cone cells
3. ganglion cells
4. rod cells

Q.

Name the area of retina which is most sensitive for forming image.

Q. What happens when light falls on a photoreceptor cell?
(i) Retinol dissociates from opsin.
(ii) The structure of opsin changes.
(iii) The membrane permeability changes.

1. i and ii
2. ii and iii
3. iii and iv
4. i and iv

Q. In human eye, fovea is the central pit of macula lutea where

1. only rods are present
2. only cones are present
3. optic nerve leaves the eye
4. cones are more than rods.

Q. Which one is the correct difference between rod and cone cell?

1. $\begin{array}{cccc}& & \text{Rod cells}& \text{Cone cells}\\ & \text{Overall function}& \text{Vision in poor light}& \text{Color vision and detailed vision in bright light}\end{array}$
2. $\begin{array}{cccc}& & \text{Rod cells}& \text{Cone cells}\\ & \text{Distribution}& \text{More concentrated in centre of retina}& \text{Evenly distributed all over retina}\end{array}$
3. $\begin{array}{cccc}& & \text{Rod cells}& \text{Cone cells}\\ & \text{Visual activity}& \text{High}& \text{Low}\end{array}$
4. $\begin{array}{cccc}& & \text{Rod cells}& \text{Cone cells}\\ & \text{Visual pigment}& \text{lodopsin}& \text{Rhodopsin}\end{array}$

Q. In the chemistry of vision in mammals, the photosensitive substance is called

1. retinal
2. sclerotin
3. rhodopsin
4. melanin

Q. When we migrate from dark to light, we fail to see for sometimes but after a time visibility becomes normal. It is an example of

1. Accomodation
2. Adaptation
3. Mutation
4. Photoperiodism

Q.

Differentiate between the following pair on the basis of what is mentioned within brackets:

Rod cells and cone cells (pigment)

Q. Which one is the correct difference between rod and cone cell?

1. $\begin{array}{cccc}& & \text{Rod cells}& \text{Cone cells}\\ & \text{Overall function}& \text{Vision in poor light}& \text{Color vision and detailed vision in bright light}\end{array}$
2. $\begin{array}{cccc}& & \text{Rod cells}& \text{Cone cells}\\ & \text{Distribution}& \text{More concentrated in centre of retina}& \text{Evenly distributed all over retina}\end{array}$
3. $\begin{array}{cccc}& & \text{Rod cells}& \text{Cone cells}\\ & \text{Visual activity}& \text{High}& \text{Low}\end{array}$
4. $\begin{array}{cccc}& & \text{Rod cells}& \text{Cone cells}\\ & \text{Visual pigment}& \text{lodopsin}& \text{Rhodopsin}\end{array}$