Question

4. a. Describe what the "blind spot" of the eye is.

b. What causes this blind spot?

c. How far from your eye is the "blond spot".

d. Describe the 2 parts to the autonomic nervous system what activities in general do they control?

Answer 1

a. Blindspot, small portion of the visual field of each eye that corresponds to the position of the optic disk (also known as the optic nerve head) within the retina. There are no photoreceptors (i.e., rods or cones) in the optic disk, and, therefore, there is no image detection in this area.

b. The natural blind spot (scotoma) is due to a lack of receptors (rods or cones) where the optic nerve and blood vessels leave the eye. Some blind spots can be caused by a simple migraine, while others can be caused by glaucoma, macular degeneration, or retinal detachment.

c. It's about 15 degrees to the right of your central vision.

d.  The two divisions of the autonomic nervous system are the sympathetic division and the parasympathetic division. The sympathetic system is associated with the fight-or-flight response, and parasympathetic activity is referred to by the epithet of rest and digest. Homeostasis is the balance between the two systems.