Final answer:
Hypotonia is the medical term used to describe a soft and flabby muscle, characterized by a flaccid appearance and weak reflexes. It contrasts with hypertonia, where there is excessive muscle tone. Understanding muscle tone is essential for comprehending muscular disorders and their impact on body movements.
Step-by-step explanation:
The term used to describe a soft and flabby muscle is hypotonia. This condition represents a decreased muscle tone and can result from damage to parts of the central nervous system or from diseases like poliomyelitis. When muscles appear hypotonic, they have a flaccid appearance and often show functional impairments, such as weak reflexes.
In contrast, excessive muscle tone is known as hypertonia, which can lead to either muscle rigidity or spasticity, depending on the underlying condition. Understanding the variation in muscle tone, including hypotonia and hypertonia, provides insight into muscular system disorders and their effects on motor functions.
Muscle fibers can undergo changes based on various factors, leading to conditions like atrophy, where muscle fibers are lost or become narrower, resulting in decreased muscle mass. This can be due to disease, lack of use, or other health conditions.
Furthermore, the muscular system is composed of organized structures, with muscle fibers bundled into fascicles and those collectively building the muscle. The muscle belly, particularly in parallel muscles, is the central body of the muscle, where a concentrated mass of muscle tissue is evident. The condition of the muscle, whether hypotonic, hypertonic, or healthy, impacts its function and appearance.