Written by Ben Bunting: BA(Hons), PGCert.
If you've ever wondered how your testicles function, you're not alone. The testicles are vital to the male reproductive system because they help produce testosterone, a male sex hormone. In addition, they serve as storage for sperm and play an important role in spermatogenesis. Keep reading to learn more about the testicles' function. In this article, we'll discuss sperm production, testicular atrophy, and spermatogenesis.
The testicles are made up of two types of cells. The germ cells transform into Leydig cells, which produce testosterone. Testicular atrophy interferes with these functions. As a result, the sperm produced will have a poor morphology or even abnormalities. Although it's possible to prevent testicular atrophy, some childhood diseases can increase the chances of developing this condition.
Symptoms of this condition include swollen veins around the testicles and difficulty in conceiving a child. Testicular atrophy may also be caused by certain diseases or medical procedures, such as having a catheter or medical device inserted into the penis. Testicular atrophy is also caused by the presence of varicoceles, enlarged veins in the scrotum.
Another cause of testicular atrophy is a lack of testosterone. After a man's reproductive years, his hormone production slows down. Certain medications can cause hormonal imbalance, and this can make testicular atrophy worse. Inflammation of the testicles is caused by orchitis, a bacterial or viral infection. Inflammation of the testes may also result from urinary tract infections or sexually transmitted diseases. Furthermore, testicular torsion, a condition that causes pain and loss of blood and oxygen to the testicles, can result in atrophy.
In one case report, an 8-year-old boy with cystic fibrosis presented with an empty scrotum. His general physical examination was normal, but his scrotum was hypoplastic. Routine blood investigations revealed low levels of LH, testosterone, and inhibin B, and elevated levels of anti-Mullerian hormone and FSH. Abdominal ultrasound confirmed the absence of the testes, and laparoscopy revealed hypotrophic spermatic vessels, a closed vas deferens, and an empty inner ring. Histological examination revealed fibrotic tissue.
In rare cases, men may develop testicular torsion. This condition affects both testicles, as well as the scrotum, which regulates the temperature around them. In cold weather, the scrotum contracts, while in warmer weather, it relaxes, making the testicles appear bigger. However, if the condition is severe, surgical treatment is the only solution.
The paired testicular arteries (IAPs) supply blood to the testicles. An additional branch of the internal iliac artery (IPA) provides blood to the testis. The testis is supplied with collateral blood by two other arteries: the cremasteric artery and the vasal artery, which arises from the abdominal aorta.
Testicular cancer is the most common cause of testicular atrophy, and is the most treatable type of this condition. Symptoms of testicular cancer vary widely, depending on the severity of the disease and the age of the patient. Most cancers of this type occur in men between the ages of 20 and 40. If your testicles don't function normally, it's important to consult a doctor.
While men don't undergo major changes in fertility, the testes do decrease in size and function. Testosterone levels also decrease gradually. A man's sex life may be interrupted by decreased levels of this hormone, which can lead to a difficulty in getting an erection. However, these changes do not mean that male fertility is completely lost. By remaining sexually active, older men are likely to experience good sex even as their testicles become smaller and weaker.
In many sexually reproducing organisms, spermatogenesis refers to the process in which primordial germ cells enter the testicles and differentiate into immature cells called spermatogonia. These immature cells are dormant until puberty, when they undergo mitosis, a process in which the cells divide to produce two daughter cells, one with the same DNA and chromosome content as the original diploid mother cell. In humans, there are 46 chromosomes, 22 pairs of autosomal genes, and one pair of sex chromosomes.
Sperm development takes place within the seminiferous tubules of the testicles. A transverse section of the testis reveals various stages of development, including the emergence of sperm cells. In particular, the seminiferous tubule contains cells that support the sperm cell immature during fetal development and later in the male reproductive system. These cells are called Sertoli's cells.
A number of factors influence the rate of spermatogenesis in the testicles, including seasonality, the reproductive lifespan, and competition between sperm. The scrotum has a unique temperature regulation system, which is critical to the development of sperm. A temperature three degrees below normal body temperature is needed for the sperm to mature. In addition to this, the testes are outside the body in a sack of skin called the scrotum. Because the testes are located outside the body, the scrotum maintains a temperature that is two degrees below the temperature of the body.
The process of spermatogenesis starts from a stem cell population. The stem cells, which originate in the outer wall of the seminiferous tubule, contain almost all nuclear material. The stem cells divide in a process called mitosis, which yields half of the new cell population as future sperm cells. In the first meiotic division, two primary spermatocytes are created, and the other half become secondary spermatocytes.
Later, spermatogenesis moves to the testicles, with the formation of sperm. Sperm is made of uniflagellar cells and contains a variety of proteins that play important roles in male fertility and motility. PRM2 substitutes for histones and packages DNA into a highly condensed complex. GAPDHS is an energy-yielding enzyme that enables the conversion of carbohydrate metabolism. Another protein, ACRV1, is associated with acrosomal membranes and may play a role in sperm motility.
The development of sperm has four distinct stages. The first is known as the acrosome stage, followed by the Golgi phase. In this phase, the acrosome is formed, and the peripheral nucleus becomes fragmented. The last is called the lobe-shaped stage, which involves elongation. The elongated spermatids are highly heterogeneous in head morphology and are fragmented.
The testicles produce sperm cells continuously, but not all areas of the seminiferous tubules will produce sperm cells at the same time. It can take up to 74 days for the immature germ cell to mature, with intermittent resting phases along the way. It's a fascinating process, and a great source of scientific knowledge. So how do the testicles produce sperm cells?
A study of the germ cells in the testicles revealed the process as multiplication, maturation, differentiation, and cytoplasm fusion. In this process, sperm cells divide from the stem cells and mature into male gametes. These testes undergo this process from puberty until old age. The entire process of spermatogenesis, which includes meiosis, is called spermatogenesis. Light microscopy allows researchers to observe the shape and functions of the spermatozoa. Reduced spermatozoa are associated with infertility.
The next stage of sperm development is spermiogenesis, during which spermatids develop into mature sex organs known as spermatozoa. Spermatids have a head, a midpiece, and tail. Each of these parts has a spermtip, which contains enzymes necessary to penetrate the female gametes, and a tail that uses a typical flagellum for locomotion. Spermatozoa then leave the testes.
Hormones affect spermatogenesis in three distinct phases. Androgens initiate qualitatively complete spermatogenesis in gonadotropin-deficient mice, whereas follicle-stimulating hormone (FSH) and estradiol are ineffective in rescuing spermatogenesis after the meiotic stage. This hormone also affects sperm cells via the Sertoli cell, but its effect on them is not yet fully understood.