Human eye has a biological control system that varies the pupil diameter to maintain constant light intensity to the retina. as the light intensity increases, the optical nerve sends a signal to the brain, which commands internal eye muscles to decrease the pupil's eye diameter. when the light intensity decreases, the pupil

Answer;

-Natural control system or biological system

Explanation;

-Natural control system is a classification of control systems. The systems inside a human being or a biological system are known as natural control systems.

-For instance, the human eye has a biological (or natural) control system that varies the pupil  diameter to maintain constant light intensity to the retina. As the light intensity increases, the  optical nerve sends a signal to the brain, which commands internal eye muscles to decrease the  pupil’s eye diameter. When the light intensity decreases, the pupil diameter increases.

-Other control systems include; man-made control system, combinational control system and also time-varying and time-invariant control systems.

cells spend most of their time in interphase

those characteristics are cellular organization, reproduction, metabolism, homeostasis, heredity, response to stimuli, growth and development, and adaptation through evolution. some things, such as a virus, demonstrate only a few of these characteristics and are, therefore, not alive