ALS, or amyotrophic lateral sclerosis, is a progressive neurodegenerative disease that affects the nerve cells, specifically the neurons, in the body. These neurons are responsible for transmitting signals from the brain to the muscles, enabling movement and coordination. As ALS attacks these nerve cells, it leads to muscle weakness, loss of motor control, and eventually paralysis. The disease primarily affects the motor neurons in the brain and spinal cord, leading to difficulties in speaking, swallowing, and breathing. While ALS does not directly impact the digestive system or endocrine system, the progression of the disease may indirectly affect these systems due to the loss of muscle control.