1. Testes
By Lisa Chiffolo and Mariana Rojas

2. The Testes: Physically
~The testis is usually between 1.57 inches to 2.75 inches long and 0.8 to 1.2 inches in diameter
~it usually weighs about 25 grams
~the testis is oval or egg-shaped
~After 7 months in the womb, the testes usually descend outside the body and are protected by the scrotum (located in the anterior inguinal region)
~The scrotum keeps the testes temperature 2˚C below normal body temperature to allow normal sperm production

3. Structure of the Testes
Male gonads are composed of numerous coiled seminiferous tubules (where spermatogenesis occurs)
Leydig cells in the testes are dispersed amoung the seminiferous tubules and produce androgens when stimulated by LH from the pituitary gland
Inside the testes there are also Sertoli cells which produce inhibin and take part in spermatogenesis when activated by FSH

4. The Testes: Chemically
~hypothalamic-pituitary-testes axis: the hypothalamus releases gonadotropin-releasing hormone (GnRH). This stimulates the pituitary gland to release luteinizing hormone (LH) and follicle-stimulating hormone (ACTH) which stimulate the production of testosterone.
~testosterone is an anabolic steroid

5. The Functions
~The testis produces 12 trillion sperm over the span of one man’s life.
~The job of testes is to produce androgens (male sex hormone) and sperm
~The most important androgen is testosterone in males
~Testosterone helps the reproductive organs grow and mature during puberty
*deepens the voice, makes facial hair grow, develops heavy muscles and bones, and allows sperm production*

6. Hypothalamus and Pituitary Interaction with Testes
The hypothalamus sends GnRH to command the pituitary to release FSH and LH.
Testes make testosterone after the pituitary sends FSH and LH as stimulation.
This process is regulated by negative feedback because after the testes are stimulated they release inhibin and testosterone which signals the hypothalamus and pituitary glands to end their hormone production.

7. Testicular Torsion
The twisting of the spermatic cord, which cuts off the blood supply to the testicle and surrounding structures within the scrotum

8. Causes and Symptoms
Torsion can result from “bell clapper” deformity, or trauma if swelling occurs
Symptoms include severe pain in one testicle, scrotal swelling, nausea or vomiting, and light-headedness

9. Diagnosis, Treatment, and Prevention
This condition is common in infancy and the beginning of adolescence
Ultrasound techniques are used to assess blood flow to testicle
Certain X-ray tests may be used
As treatment, surgery should be performed as soon as possible after symptoms begin
If the blood flow is impaired for 6 hours, the testicle will atrophy and die, and will have to be removed
Use precautions to avoid trauma to the scrotum
Many cases are not preventable

10. Hypogonadism
A disorder in which the testicles do not produce enough testosterone, a hormone that play a key role in masculine growth and development during puberty

11. Causes
Causes of primary hypogonadism are Klinefelter’s syndrome, undescended testicles, hemochromatosis, testicular trauma, cancer treatment, and mumps orchitis
Causes of secondary hypogonadism are Kallmann syndrome, normal aging, pituitary disorders, medications, HIV/AIDS, obesity, and inflammatory disease

12. Symptoms
Symptoms in fetal development include female genitals, ambiguous genitals, or underdeveloped male genitals
Symptoms in puberty include decreased development of muscle mass, lack of deepening of the voice, impaired growth of the penis, testicles, and body hair, excessive growth of the arms and legs in relation to the trunk, and gynecomastia
Symptoms in adulthood include erectile dysfunction, infertility, decrease in muscle mass and body hair growth, gynecomastia, osteoporosis, fatigue, decreased sex drive, difficulty concentration, and hot flashes

13. Diagnosis, Treatment, and Prevention
Tests such as hormone testing, semen analysis, pituitary imaging, genetic studies, and testicular biopsies are done to determine if one has primary or secondary hypogonadism
Treatment for hypogonadism depends on the cause
Treatment for adults includes hormone replacement (TRT), surgery, and medication
Treatment for boys is Testosterone Replacement Therapy (TRT) by injection, patch, gel, gum and cheek, and oral methods
Hypogonadism is not preventable

14. Orchitis
A condition involving inflammation, swelling, and frequent infection of one or both of the testicles

15. Causes and Symptoms
Causes of bacterial orchitis include epididymitis and STDs
Cause of viral orchitis is most likely the mumps
Symptoms include testicular swelling and tenderness, pain, nausea, fever, discharge from penis, and blood in the ejaculate

16. Diagnosis, Treatment, and Prevention
Tests such as STD screening, urinalysis, ultrasound imaging, and nuclear scans of the testicles are done to reach a diagnosis
Treatment depends on the cause of orchitis
Treatment for bacterial orchitis includes antibiotics
Treatment for viral orchitis includes pain medication, anti-inflammatory drugs, and bed rest
Safer sex behaviors will decrease chances of developing STD-related bacterial orchitis
Getting vaccinated against mumps will prevent mumps-related viral orchitis

17. Works Cited http://www.innerbody.com/image_endoov/repo10-new2.html
Campbell and Reese. “Biology: Ninth Edition” Benjamin Cummings

18. Works Cited (continued)

19. Works Cited (Pictures)