Contents of the scrotum: Epididymis, Vas deferens, Spermatic cord and Cremaster muscle

len Alfred Ajibola - 25th November, 2021 @ 11:55 AM

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Contents of the scrotum: Epididymis, Vas deferens, Spermatic cord and Cremaster muscle Fun facts in Biology

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Contents of the scrotum:

Apart from the testicles, other male reproductive structures found in the scrotum include the epididymis, vas deferens, spermatic cord and cremaster muscle.

Please read an introduction to the scrotum and testicles here.


  • Epididymis

The epididymis is a comma-shaped, long, narrow and highly convoluted or coiled tubule. It has a length of 6 to 7 meters and can be seen on the superior, lateral and posterior sides of each testis. It is shown in the image below:


Epididymis - Len Academy

You can read on seminal vesicles and bulbourethral glands here.

The epididymis is a muscular tube that connects each testicle to the vas deferens via the ductuli efferentes testis. It is divided into 3 parts. These are:

  1. Head of the epididymis

  2. Body of the epididymis

  3. Tail of the epididymis


The head of the epididymis receives sperm cells from the ductuli efferentes testis. Its walls comprises of a thick epithelium and a few smooth muscle. Functionally, the head of the epididymis absorbs fluid from the spermatozoa (sperm cells), mildly concentrating them in the process.

The body of the epididymis is made up of an epithelium and smooth muscle with intermediate thickness. Its contractions propels the spermatozoa downwards.

The tail of the epidermis has the thinnest epithelium. In comparison to other parts of the epididymis, it has the greatest quantity of smooth muscle. Sperm cells are moved into the vas deferens from here.


The epididymis generally serves the following functions:

  1. It stores sperm for about 80 days, bringing them to maturity.

  2. It improves sperm motility by absorbing some of the fluids produced by the testicles during sperm formation.

  3. The epididymis protects the sperm cells.

  4. The epididymis leads into another tubule called the vas deferens. The smooth muscles surrounding the epididymis aid in propelling sperm into the vas deferens via their contractions.

You can read on the male external genitalia (penis) here.


  • Vas Deferens

The vas deferens is found both within and above the scrotum. It is a long muscular tube that begins at the tail of the epididymis and runs through the ejaculatory ducts.

The contraction of the smooth muscles of the vas deferens helps in propelling sperm during ejaculation. Also, as sperm move from the vas deferens into the urethra, secretions are added into it from the male accessory sex glands.

Please read on the male accessory sex organs here.

The vas deferens is also called the ductus deferens.

Vas deferens - Len Academy

The function of vas deferens is to move or transport sperm from the epididymis into the ejaculatory ducts during the process of ejaculation. Simply put, you can consider the vas deferens as the transport system responsible for sperm movement from the epididymis to the ejaculatory ducts.


  • Spermatic Cord

This is a cord-like structure formed by the vas deferens. It plays an important role in the supply of blood to the testes and vas deferens. It also aids the movement of sperm out of the epididymis into the ejaculatory ducts.

Below is an image showing the contents of the spermatic cord:
Testis - Len Academy

The spermatic cord contains a large amount of blood vessels and nerves. Functionally, these vessels supply blood to the testes, epididymis and cremaster muscles while its nerves assist in transferring information back and forth from the scrotum, testicles and the cremaster muscles respectively.

You can read on the red blood cells here.

Permanently swollen veins (called varicose veins) may be formed in the vessels of the spermatic cord, resulting to a condition termed varicocele. In most cases, varicocele is asymptomatic, although fertility issues may result seldomly in patients.


  • Cremaster Muscles

The cremaster muscle surrounds the testis and is found only in males. They help in the movement of the testicles towards the body and away from it. The goal of these movements is to achieve an ideal temperature for sperm formation.

Unlike other internal organs, recall that the testes aren't located inside the body. It sits comfortably inside the scrotum, with the latter located outside the body. The temperature of the testis inside the scrotum is crucial for sperm formation. In fact, it is the cremasater muscle the moves the scrotum towards or away from the body, depending on the external temperature.

Cremaster muscle - Len Academy

In comparison to the internal body temperature of 36.5oC, understand that both testes requires a slightly cooler temperature (around 34oC) for sperm formation.

In an environment with a cooler temperature, the cemaster muscle contracts, moving the testes towards the body. In this manner, the scrotal temperature is slightly raised against the environmental temperature. Conversely, when the environmental temperature is warmer, the cremaster muscle relaxes, thus pushing the testes away from the body.

Please read on homeostasis here.


The concept of the cremasteric reflex refers to an immediate action taken by the cremaster muscle whenever the inner thigh is stimulated. In this regard, the cremaster muscle automatically raises the testes towards the body. The inner thigh in the above instance refers to a region between the medial part of the hip and knee.

You can read on bones of the human skeleton here.

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Alfred Ajibola is a Medical Biochemist, a passionate Academician with over 7 years of experience, a Versatile Writer, a Web Developer, a Cisco Certified Network Associate and a Cisco CyberOps Associate.

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