What are the differences between voluntary and involuntary actions?

Voluntary actions are consciously controlled by the brain, while involuntary actions are automatic responses not consciously controlled.

Voluntary actions are those that we consciously decide to carry out. These actions are controlled by the somatic nervous system, which is a part of the peripheral nervous system. This system is responsible for carrying sensory and motor information to and from the central nervous system. Voluntary actions involve the use of skeletal muscles, which are under our conscious control. Examples of voluntary actions include walking, talking, writing, and eating.

On the other hand, involuntary actions are those that occur without our conscious control. These actions are controlled by the autonomic nervous system, which is also a part of the peripheral nervous system. The autonomic nervous system controls the functions of our internal organs, such as the heart, stomach, and intestines. It is further divided into the sympathetic and parasympathetic nervous systems, which control our body's automatic responses to certain stimuli. For instance, the sympathetic nervous system prepares our body for 'fight or flight' in response to danger, while the parasympathetic nervous system helps our body to 'rest and digest'. Examples of involuntary actions include heartbeat, digestion, and pupil dilation in response to light.

IGCSE Biology Tutor Summary: Voluntary actions are those we consciously control, like walking or eating, and are managed by the somatic nervous system. Involuntary actions happen automatically, like our heartbeat or digestion, controlled by the autonomic nervous system. The former involves skeletal muscles, while the latter deals with internal organs, governed by either the sympathetic or parasympathetic nervous systems, depending on the body's needs.