During puberty, testosterone and other hormones cause these cells to transform into sperm cells. The cells divide and change until they have a head and short tail, like tadpoles. The head contains genetic material genes. The sperm move into the epididymis, where they complete their development. The seminal vesicles and prostate gland make a whitish fluid called seminal fluid, which mixes with sperm to form semen when a male is sexually stimulated. The penis, which usually hangs limp, becomes hard when a male is sexually excited.
Tissues in the penis fill with blood and it becomes stiff and erect an erection. The rigidity of the erect penis makes it easier to insert into the female's vagina during sex. When the erect penis is stimulated, muscles around the reproductive organs contract and force the semen through the duct system and urethra.
Semen is pushed out of the male's body through his urethra — this process is called ejaculation. Each time a guy ejaculates, it can contain up to million sperm. If semen is ejaculated into a female's vagina, millions of sperm "swim" up from the vagina through the cervix and uterus to meet the egg in the fallopian tube. It takes only one sperm to fertilize the egg. This fertilized egg is now called a zygote and contains 46 chromosomes — half from the egg and half from the sperm.
Genetic material from the male and female combine so that a new individual can be created. The zygote divides again and again as it grows in the female's uterus, maturing over the course of the pregnancy into an embryo, a fetus, and finally a newborn baby. What Is Reproduction? What Is the Male Reproductive System? Two groups of female sex hormones are produced in the ovaries, the estrogens and progesterone.
These steroid hormones contribute to the development and function of the female reproductive organs and sex characteristics. At the onset of puberty, estrogens promotes:. Orchitis usually disappears in days. You can be born with this condition.
It can also happen due to an injury, infection, or other condition that affects testosterone production. Hypogonadism is usually treated with hormone replacement therapy. Testicular cancer happens when cancerous cells multiply within the tissue of your testicles.
It commonly starts in the tubular testicle structures that help produce sperm. Sometimes, your doctor can surgically remove the affected tissue.
In other cases, you may need to have an entire testicle removed. Radiation therapy or chemotherapy can also help destroy cancer cells. Roll each testicle around in your scrotum using your fingers.
Check for lumps and swollen or tender areas. Take a shower or bath every day to keep your entire genital area clean. This reduces your risk of infections that can cause other complications. Keep your penis and scrotal area dry after bathing. Moisture trapped in the area can quickly become a breeding ground for bacteria. Try to avoid wearing tight underwear and pants.
Allow your scrotum to hang naturally from your body to help keep the scrotal temperature low and prevent injury. Wear a condom when doing any kind of sexual activity involving your penis. This helps to prevent sexually transmitted diseases that affect your scrotum and testicles.
The scrotum or scrotal sac is a part of the external male genitalia located behind and underneath the penis. It is the small, muscular sac that…. The male urethra connects the urinary bladder to the penis. Once the bladder becomes full, urine flows through the urethra and leaves the body at the…. The left testicular vein is the male equivalent of the ovarian vein.
Both testicles have veins that attach at different locations. The right…. On each side of the prostate gland in the male reproductive system is an ejaculatory duct. Each ejaculatory duct is about two centimeters in length…. The epididymis is a long, coiled tube that stores sperm and transports it from the testes.
It appears as a curved structure on the posterior back …. The glans penis can be described as the rounded head or tip of the penis. Magnification: x The testes, also known as testicles or male gonads, lie behind the penis in a pouch of skin called the scrotum. The testes move freely in the scrotum but each testis is attached to the body wall by a thin cord called the spermatic cord, which passes through a cavity in the pelvis and into the abdomen.
The cord contains the nerves and blood vessels for the testes as well as the vas deferens, which carries the sperm from the testes into the urethra; the urethra is the passageway for sperm to the outside of the body at ejaculation. The testes lie outside of the body and are maintained at a temperature about two degrees Centigrade lower than the body's core temperature.
This is because sperm production and quality is optimal at this lower temperature. The testes have two functions — to produce sperm and to produce hormones, particularly testosterone. Sperm are produced in the seminiferous tubules of the testes.
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