Which muscle type is considered involuntary and not under conscious control?

The correct answer is smooth muscles, which are characterized by being involuntary and not under conscious control. Smooth muscles are found in various systems of the body, including the digestive tract, blood vessels, and respiratory passages. They function automatically to perform essential activities such as moving food through the intestines and regulating blood flow by changing the diameter of blood vessels.

In contrast, skeletal muscles are under conscious control and are used for voluntary movements, such as walking and lifting objects. Striated muscles primarily refer to skeletal muscles due to the presence of a striped appearance seen under a microscope; however, cardiac muscles, which also have a striated appearance, are involuntary and found only in the heart. Despite their striations, cardiac muscles still function automatically, distinguishing them from voluntary skeletal muscles. However, when considering muscle types that are strictly involuntary and not consciously controlled, smooth muscles are the definitive answer.