In smooth muscle these transitionally alternating muscle fibers help to serve the actions of peristalsis. As the circular fibers contract the tube (lumen) constricts and as the longitudinal fibers contract it opens up the lumen.
No. Muscles at the base of the bladder contract in order to close off the passageway from the bladder into the urethra, the tube through which urine and semen leave the body.
Sounds like you're talking about Peristalsis (if you're looking for the actual name). Basically, as I understand it, the intestines have muscles that do two different things. One set is circular and contracts to basically squeeze the tube. The longitudinal muscles contract along the length of the intestine and help to propel the food onward. Everything happens in a wave-like motion with the circular muscles contracting to squeeze the food forward more and more and to prevent the food from being able to more backward, while the longitudinal muscles move the whole thing onward.
No. A capillary is a small tube carrying blood, a muscle is a group of cells that can contract, generally in order to move something.
Peristalsis involves circular smooth muscles and longitudinal smooth muscles in the effort to produce waves of contractions in a tube. This process is used in digestion to move the food (bolus) through the esophagus and the chyme (partially digested food) through the intestines.
No, eye balls are circular.
These muscles are called the tunica muscularis.
lens
These muscles are called the tunica muscularis.
Peristalsis is a symmetrical contraction of muscles which propagates in a wave down the muscular tube, more specifically the esophagus. In humans, peristalsis is found in the contraction of smooth muscles to propel contents through the digestive tract.In much of the gastrointestinal tract, smooth muscles contract in sequence to produce a peristaltic wave which forces a ball of food (called a bolus while in the esophagus and gastrointestinal tract and chyme in the stomach) along the gastrointestinal tract. Peristaltic movement is initiated by circular smooth muscles contracting behind the chewed material to prevent it from moving back into the mouth, followed by a contraction of longitudinal smooth muscles which pushes the digested food forward.
The shape of the chief cells of the skeletal muscles is that they are tube-shaped.
auditory (pharyngotympanic) tube