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精子运输
精子从起源到射精的旅程始于睾丸的生精小管内。在这里，塞托利细胞产生液体，推动非运动精子通过一系列管道，从直管开始，通向睾丸网。这种相互连接的细管网络作为精子的初始通道，引导它们进入输出小管，然后进入附睾进行成熟。
成熟阶段发生在附睾中，精子需要两到三周的时间才能获得受精所需的运动能力和成熟度。这种转…
在睾丸的生精小管内，支持细胞产生的液体将无活动能力的精子经由一系列直管推入睾网。
精子从这些相互连接的小管被输送至盘曲的输出小管。
精子通过输出小管离开睾丸，进入附睾内的附睾管，在此过程中经历成熟。
经过两到三周，精子在附睾中通过并获得运动能力和成熟度，从而能够使卵子受精。
附睾的蠕动收缩将成熟精子推进至输精管。
在输精管内，成熟的精子保持不活跃状态，维持较低的代谢率。
在性兴奋期间，蠕动性收缩将储存的精子推向射精管。
射精管穿过前列腺，将精子排入前列腺部尿道。
射精过程中，成熟的精子和附属腺体的液体通过尿道排出体外。
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Q1: How do sperm move through the seminiferous tubules and into the epididymis?
Sertoli cells within seminiferous tubules produce fluid that pushes non-motile sperm through straight tubules into the rete testis. From this interconnected network, sperm enters the efferent ductules and then the epididymis, where they begin their maturation journey over two to three weeks.
Q2: What changes occur to sperm during their time in the epididymis?
During their two to three week transit through the epididymis, sperm acquire motility and maturity necessary for fertilization. Peristaltic contractions of the epididymis facilitate this transformation and propel the mature sperm into the vas deferens, where they can be stored for extended periods.
Q3: How long can sperm remain viable in the vas deferens?
Mature sperm stored in the vas deferens maintain a low metabolic rate and can remain viable for months without losing their fertilizing potential. This storage capability allows the body to preserve sperm until sexual arousal triggers ejaculation through peristaltic contractions.
Q4: What role do peristaltic contractions play in sperm transport?
Peristaltic contractions propel sperm through multiple reproductive structures. These muscular waves move mature sperm from the epididymis into the vas deferens and, during sexual arousal, push stored sperm toward the ejaculatory ducts for eventual expulsion during male sexual response erection ejaculation.
Q5: Where do the ejaculatory ducts deliver sperm before ejaculation?
The ejaculatory ducts pierce through the prostate gland and empty sperm into the prostatic urethra. During ejaculation, mature sperm and fluid from accessory glands of the male reproductive system are expelled from the body through the urethra during this process.
Q6: What is the role of the rete testis in sperm transport?
The rete testis is an interconnected network of tubules that receives non-motile sperm from the seminiferous tubules. This structure acts as a crucial intermediate pathway, directing sperm from the straight tubules into the efferent ductules and ultimately into the epididymis for maturation.
Q7: How does sympathetic nervous system stimulation affect sperm transport during ejaculation?
During sexual arousal and ejaculation, sympathetic nervous system stimulation triggers peristaltic contractions in the vas deferens. These coordinated muscular contractions propel stored sperm toward the ejaculatory ducts, combining with fluids from accessory glands before expulsion through the urethra during this process.