Question

Which of the following occurs during micturition?

1) The detrusor muscles relax, muscles of the internal urethral sphincter relax, and muscles of the external urethral sphincter relax.
2) The detrusor muscles contract, muscles of the internal urethral sphincter contract, and muscles of the external urethral sphincter contract.
3) The detrusor muscles relax, muscles of the internal urethral sphincter contract, and muscles of the external urethral sphincter contract.
4) The detrusor muscles relax, muscles of the internal urethral sphincter contract, and muscles of the external urethral sphincter relax.
5) The detrusor muscles contract, muscles of the internal urethral sphincter relax, and muscles of the external urethral sphincter relax.

Answer 1

During micturition, the detrusor muscles contract, the internal urethral sphincter relaxes, and the external urethral sphincter also relaxes to allow urine to leave the body. (option 1)

Step-by-step explanation:

Micturition, also known as the process of urination, involves a coordinated series of muscle contractions and relaxations. In this process, the detrusor muscles, which are smooth muscles of the bladder wall, relax to allow the bladder to expand and store urine. Simultaneously, the muscles of the internal urethral sphincter relax, facilitating the release of urine from the bladder into the urethra. The muscles of the external urethral sphincter, which are under voluntary control, also relax to permit the controlled expulsion of urine from the body.

Micturition is a complex process that involves the coordinated relaxation of detrusor muscles, internal urethral sphincter, and external urethral sphincter. This orchestrated sequence of muscle actions ensures the effective and controlled elimination of urine from the bladder.