The smooth muscle found in the iris of the eye and the walls of blood vessels, which contracts in response to neurotransmitters and hormones, is known as a ________ smooth muscle.

Smooth Muscle

A type of muscle found in the walls of internal organs such as the stomach, intestines, and blood vessels, responsible for involuntary movements.

Iris

The colored part of the eye surrounding the pupil, controlling light levels inside the eye by adjusting the size of the pupil.

Blood Vessels

Cylindrical vessels that transport blood across the body, encompassing veins, arteries, and capillaries.