What is function of iris ? What is persistence of vision?
Answers
Answer:
Iris is responsible for controlling the diameter and size of the pupil and thus the amount of light reaching the retina .
Persistence of vision means the image stays on the retina for about 1/16 of a second.This feature is called as persistence of vision.
ANSWER:
Controlling the diameter and size of the eye pupil and determining the eye colour are the main functions of iris.
Persistence of vision is the retention of the image of a vision in human brain.
EXPLANATION:
Iris is a lean circular structure in human eye consisting of two layers- stroma and epithelial cells. The sphincter muscle connected to the stroma contracts the pupil of the eye and the dilator muscle enlarges the pupil by pulling the Iris.
The presence of 'melanin pigment' in different quantities in iris determines the phenotypic eye colour of a human.
The persistence of vision is the retention of a visual image of an object for a certain time in human brain when the object is not present. It is a phenomenon that creates an 'illusion of movement' while watching moving pictures.