motiliteten

Motiliteten, or motility in English, refers to the ability of an organism or cell to move or to move substances within its body. The term is used across biology to describe movement at different scales: from single cells that propel themselves with flagella or cilia to multicellular animals that move through muscle contraction, and to the movement of contents through hollow organs such as the digestive tract.

Motility arises from diverse mechanisms. Cellular motility relies on the cytoskeleton and motor proteins: actin and myosin drive crawling movements, while microtubules and associated motors support intracellular transport and the beating of cilia and flagella. In animals, muscle contraction enables voluntary and involuntary movement; smooth and cardiac muscles use distinct regulatory pathways to convert chemical energy into force. In hollow organs, rhythmic contractions coordinate the propulsion of contents, often organized by specialized pacemaker cells.

In humans and many animals, motility is tightly regulated by nervous and hormonal signals. The gastrointestinal tract, for example, is controlled by the enteric nervous system, autonomic input, and local mediators such as hormones that influence the speed and pattern of contractions. Pacemaker activity in the gut helps generate rolling waves of movement, such as peristalsis, to move food forward.

Clinical relevance: Disturbances in motility can lead to disorders such as gastroparesis (delayed gastric emptying), gastroesophageal reflux disease with impaired clearance, irritable bowel syndrome with dysmotility, and chronic intestinal pseudo-obstruction. Assessment methods include manometry, imaging studies, and transit tests. Treatments include prokinetic medications, dietary adjustments, and, in some cases, surgical or device-based interventions. Research in motility spans physiology, gastroenterology, neurobiology, and reproductive biology.