Once sperm production starts, it will typically continue uninterrupted until death, though discernible defects in sperm quality and quantity increase with age. A healthy male reproductive system will produce around 50— million viable sperm each day. The whole process of spermatogenesis, from newly formed sperm to a fully mature one, usually takes around 74 days. These divisions of the sperm cells create genetic variation.
At this point, the sperm cells that have divided are still connected with cytoplasm. In the next step, the spermatids begin to mature, a process driven by the male hormone testosterone.
They form a tail and an acrosome, their DNA becomes more compact, and excess cytoplasm is removed to create individual structures. At this point, sperm are still immotile unable to move on their own. They are transported via muscle contractions to the epididymis, a coiled tube behind each testicle, where they mature further, gaining the ability to move on their own and fertilize an egg.
Relatively cool temperatures are important for spermatogenesis. Here, sperm mixes into the semen before moving to the urethra for ejaculation.
On average, anywhere between 80 and million sperm cells are released per ejaculation. However, most are eliminated along the way; any abnormal or otherwise defective sperm fall to the many dangers of the journey, along with a good percentage of healthy sperm. In fact, less than 1 in a million from the original ejaculate will reach the egg at the time of fertilization.
The journey to the egg is complex, full of obstacles, and at times hostile. However, if these changes are ongoing and accompany other symptoms, such as a foul odor, or prolonged hematospermia, a person can consult with a doctor. If a person notices any signs of prostate issues, they should also see a doctor. These may include difficulty urinating, swelling in the genital and pelvic region, experiencing pressure in the colon, or constantly feeling the need for a bowel movement.
Normal semen is generally a clear, white, or gray color. Changes in its color may be temporary and may resolve without medical treatment. However, if people experience changes in semen that do not go away or come with other symptoms, such as infection or inflammation, they should seek medical attention. Injuries, infections, problems with the prostate, and many other conditions can cause blood to appear in the semen. Learn more about the causes and….
Semen is a gel-like fluid that contains sperm, which can fertilize an egg. Usually, it is whitish-gray, but any changes in the reproductive glands, or…. Ejaculating multiple times per day, living with certain medical conditions, and having nutritional deficiencies can all cause watery semen.
Semen consistency, volume, quality, and color can naturally change from day to day. We look at the causes of unusually thick semen and its…. The smell of semen could be nothing to worry about or it can point to an underlying condition. Here we discuss what smells are normal and what others…. Why does semen color change and what does it mean? Semen color changes Causes Different textures When to see a doctor Summary Healthy semen is a cloudy white color with a jelly consistency similar to a raw egg.
Why semen color changes. What different textures may mean. When to see a doctor. Scientists identify new cause of vascular injury in type 2 diabetes. Adolescent depression: Could school screening help? Related Coverage. Why is there blood in my semen? Why is my semen yellow? Medically reviewed by Daniel Murrell, MD. What causes watery semen, and does it affect fertility? Medically reviewed by Alana Biggers, M. What does semen smell like and why? A variation of this type of sperm is the Decondensing head sperm seen when the sperm prematurely starts to break down its nucleus and the unraveling DNA material fills the entire sperm head.
Headless sperm. Headless sperm have no head at all and are called acephalic sperm or decapitated sperm syndrome. They do not have genetic material or chromosomes. This type of sperm may look like a pinhead sperm but upon close examination, one can see that there is no tiny sperm head giving the sperm the appearance of a loose piece of string.
Tail-less sperm. Tail-less sperm are called acaudate sperm, and these sperm are often seen during necrosis, the death of most or all of the cells in an organ.
Nuclear vacuoles sperm. Nuclear vacuoles sperm have two or more large vacuoles cyst-like bubbles or multiple small vacuoles in the sperm head. These nuclear vacuoles are visible under high magnification microscopy. While some studies show this type of sperm has low fertilization potential, other studies have shown no effect. Studies are still in progress. Multi-head sperm. Multiple parts sperm can have multiple heads or tails. When the sperm has two heads, it is called a duplicate sperm, a condition linked to exposure to toxic chemicals, heavy metals like cesium, smoke or high prolactin hormone in the male.
Thick, swollen neck. Large swollen midpiece or sperm neck may be related to defective mitochondria, the energy-making parts of the sperm cell. It may also be a sign that the centrioles, the guidance system for moving chromosomes stored at the sperm neck, may be missing or broken.
Coiled-tail sperm. Coiled-tail sperm have been exposed to either incorrect seminal fluid conditions or the presence of bacteria. These sperm cannot swim, as their tails are damaged. Heavy smoking has been linked to the presence of coiled-tail sperm. Stump tail sperm. Sperm cells with short tails often have low or no motility and are called stump tail or Dysplasia of Fibrous Sheath DFS sperm.
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