MEDICAL
URETERS
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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True
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False
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Either A or B
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None of the above
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Detailed explanation-1: -Urine is moved through the ureters in peristaltic waves. Calmodulin activates myosin light-chain kinase in ureteral smooth muscle, causing contraction and electrical pacemaker cells in the proximal renal pelvis, controlling the frequency of these waves (in humans 1–6 waves per minute).
Detailed explanation-2: -Urine drains from the renal pelvis of each kidney into the ureters. The ureters are long, thin tubes made of smooth muscle. Contractions of the smooth muscle push urine down through the ureters and into the bladder.
Detailed explanation-3: -As urine passes through the ureter, it does not passively drain into the bladder but rather is propelled by waves of peristalsis. The ureters are approximately 30 cm long. The muscular layer of the ureter creates the peristaltic contractions to move the urine into the bladder without the aid of gravity.
Detailed explanation-4: -Ureteral peristalsis is the process by which urine is propelled from the kidney to the bladder, and is generated secondary to contraction of the smooth muscles in the wall of the ureter (1). The mechanisms underlying the propagation of a peristaltic wave in the ureter are not well understood.