Question

1. What is a normal sperm count?

2. Describe the two stages of the male sexual response. Don’t forget ANS control.

3. Describe the duct system of the male reproductive system beginning with seminiferous tubules.

Answer 1

Ans1:

Normal Sperm Count: A normal sperm count ranges from 15 million sperm to more than 200 million sperm per milliliter (mL) of semen.

Ans 2:

Ans 3: Duct System of Male Reproductive System:

• The duct system of the male reproductive tract begins at the mediastinum testes (hilus) and consists of the ductuli efferentes, the epididymis, the vas deferens with its ampulla, and the ejaculatory duct. A large fraction of the fluid leaving the testis with spermatozoa is reabsorbed by the epithelia of the ductuli efferentes and the upper portion of the epididymis. Spermatozoa leaving the testis appear morphologically complete but are unable to fertilize eggs. Further maturation takes place as they pass slowly through the epididymis (several weeks).
• The ductuli efferentes are 10 to 15 small coiled ducts with a few layers of smooth muscle in their walls. The convoluted ductules empty into a single larger tube, the ductus epididymis. This is an extremely long (4-6 meters) tortuous tube with a thin muscle coat. An outer fibrous tunic binds the whole mass to form the epididymis. The epididymis is divided into head, body, and tail, the duct being smallest and most convoluted in the head where reabsorption of fluids predominates. Towards the tail, the duct gradually straightens and enlarges, acquiring a thicker muscular coat that becomes continuous with the vas deferens. Spermatozoa are stored in the body and tail, however the ionic medium maintained by the epithelium is such that they are non-motile and conserve stored energy.
• The vas deferens (ductus deferens) is a tube with an extremely thick muscular wall. It is bound by connective tisue with blood vessels, nerves and lymphatics to form the spermatic cord which passes from a male reproductive organ into the abdominal cavity. The lumen of the vas deferens has an irregular outline due to longitudinal folds of the mucosa, and it is lined by a pseudostratified epithelium that is lower than that of the ductus epididymis. Some cells have stereocilia, but the latter tend to disappear toward the ampulla. The ampulla is a fusiform dilation of the vas in the abdominal cavity, just before it receives the duct of the seminal vesicle. After receiving the duct of the seminal vesicle, the vas is reduced in diameter and becomes the ejaculatory duct which empties into the prostatic urethra. There are numerous folds and glandular pockets, but these are less prominent than in the ampulla; the epithelium is simple or pseudostratified columnar, becoming transitional near the urethra.
• With the scanning lens, locate a group of tubules with a much taller, very regular epithelium near the large dilated ductules; this is the beginning of the coiled ductus epididymis lined with a pseudostratified columnar epithelium with stereocilia. A layer of smooth muscle cells, 2 or 3 layers thick, is apposed to the basement membrane of this epithelium.