On average, it is roughly the size of a walnut or a ping-pong ball. It weighs around 1 ounce 30 grams and is usually soft and smooth to the touch. The prostate sits deep in the pelvis, between the penis and the bladder. It is possible to feel the prostate gland by placing a finger into the rectum and pressing toward the front of the body. The urethra, a tube that carries urine and semen out of the body, passes through the prostate.
Because the prostate surrounds this tube, prostate problems can affect urine flow. This organ is one part of male sexual, or reproductive, anatomy. The other parts include the penis, scrotum, and testes. The prostate is not essential for life, but it is important for fertility.
The following sections discuss the functions of the prostate. The primary function of the prostate is to contribute prostatic fluid to semen. Prostatic fluid contains components that make semen an ideal substance for sperm cells to live in, including enzymes, zinc, and citric acid.
One important enzyme is prostate-specific antigen PSA , which helps make the semen thinner and more fluid. The fluid in semen helps the sperm travel down the urethra and survive the journey towards an egg, which is essential for reproduction.
Prostatic fluid is slightly acidic, but other components of semen make it alkaline overall. This is to counteract the acidity of the vagina and protect the sperm from damage. During ejaculation, the prostate contracts and squirts prostatic fluid into the urethra.
Here, it mixes with sperm cells and fluid from the seminal vesicles to create semen, which the body then expels. When the prostate contracts during ejaculation, it closes off the opening between the bladder and urethra, pushing semen through at speed. This is why, in normal anatomic situations, it is impossible to urinate and ejaculate simultaneously. The prostate needs androgens, which are male sex hormones, such as testosterone to function correctly.
The prostate contains an enzyme called 5-alpha-reductase, which converts testosterone into a biologically active form called dihydrotestosterone DHT.
This hormone is important for normal prostate development and function. In the developing male, it is crucial for the development of secondary sex characteristics, such as facial hair. A capsule of connective tissue that contains muscle fibers surrounds the prostate. This capsule makes the prostate feel elastic to the touch. Scientists often categorize the prostate into four zones that surround the urethra like layers of an onion.
The following layers make up the prostate, beginning with the outer capsule and ending inside the prostate:. Prostate conditions often cause problems with urination or bladder control. What Does the Prostate Do? The prostate is not essential for life, but it is important for reproduction. Healthy semen is the perfect consistency and environment for sperm transit and survival, and for fertilization.
Semen includes enzymes like PSA which is often measured as part of screening for prostate cancer , as well as other substances made by the seminal vesicles and prostate, such as zinc, citrate, and fructose that actually gives sperm energy to make the journey to the egg.
Semen also contains substances that may protect the urinary tract and sperm from bacteria and other pathogens. The prostate typically grows during adolescence, under the control of the male hormone testosterone and its byproduct dihydrotestosterone DHT. Testosterone is primarily made in the testes, but a smaller amount it is also made in the adrenal glands above the kidneys.
Bacteria, Infection, Inflammation… Cancer? Guess what? This may be bad news for people like TV survival expert Bear Grylls, who often resorts Prostate Gland. The prostate is a part of the male reproductive system, which includes the penis, prostate, seminal vesicles, and testicles.
The prostate is located just below the bladder and in front of the rectum. It is about the size of a walnut and surrounds the urethra the tube that empties urine from the bladder. It produces fluid that makes up a part of semen. As a man ages, the prostate tends to increase in size. This can cause the urethra to narrow and decrease urine flow. This is called benign prostatic hyperplasia, and it is not the same as prostate cancer. Men may also have other prostate changes that are not cancer.
0コメント