Autonomic and sympathetic Nervous System:
The somatic nervous system (SNS) and the autonomic nervous system (ANS)
are two key divisions of the peripheral nervous system. The somatic nervous
system is responsible for voluntary movements and controls the actions of
skeletal muscles through neurotransmitters like acetylcholine (ACH). This system
is involved in conscious, deliberate actions such as walking, lifting, and other
forms of motor control. Acetylcholine plays a crucial role in transmitting signals
from nerves to muscles, ensuring smooth, coordinated muscle contractions.
In contrast, the autonomic nervous system regulates involuntary functions like
heart rate, digestion, and respiratory rate. The ANS is further divided into the
sympathetic and parasympathetic nervous systems. The sympathetic nervous
system, often called the “fight or flight” system, prepares the body for stressful
situations by increasing heart rate, dilating pupils, and redirecting blood to
muscles. On the other hand, the parasympathetic nervous system, known as the
“rest and digest” system, promotes relaxation and recovery, slowing heart rate
and enhancing digestion once the stressful event has passed. Together, these
systems work to maintain the body’s internal balance, or homeostasis.
