Final answer:
Option 1,2.
The false statements regarding the micturition process are statements 1 and 2. Statement 1 is incorrect because detrusor muscle contraction results from parasympathetic stimulation, and statement 2 is false because relaxation of the internal sphincter is due to parasympathetic activity.
Step-by-step explanation:
The micturition process involves both involuntary and voluntary muscle controls to expel urine from the bladder. Out of the four given statements about micturition, the false statements are:
- Detrusor muscle relaxation results from sympathetic stimulation due to bladder wall stretch receptors sending afferent impulses to the lumbar spinal cord.
- There is increased activity of the parasympathetic motor neurons that control the smooth muscle relaxation of the internal urethral sphincter.
Statement 1 is false because the detrusor muscle contraction (not relaxation) results from parasympathetic stimulation due to bladder wall stretch receptors sending afferent impulses to the sacral region of the spinal cord, not the lumbar region. The sympathetic stimulation actually helps keep the detrusor muscle relaxed.
Statement 2 is also incorrect because parasympathetic stimulation leads to the contraction of the detrusor muscle and relaxation of the internal urethral sphincter, not increased activity for its relaxation.
Statement 3 is partially true; the external sphincter must be relaxed voluntarily to void urine, but the internal sphincter relaxes involuntarily in response to parasympathetic stimulation.
Statement 4 correctly states that the external sphincter relaxes as a result of the parasympathetic reflex, which is influenced by somatic nerves under voluntary control.
The please mention correct option in the final answer are statements 1 and 2.