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 [tes´tēz] (L.)
plural of testis.


Plural of testis.


/tes·tes/ (tes´tēz) [L.] plural of testis.


Plural of testis.


the two male gonads that produce sperm and testosterone.


Plural of testis.


(tes'tis) plural.testes [L.]
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The male gonad; testicle. It is one of two reproductive glands located in the scrotum that produce the male reproductive cells (spermatozoa) and the male hormones testosterone and inhibin. See: illustration


Each is an ovoid body about 4 cm long and 2 to 2.5 cm in width and thickness, enclosed within a dense inelastic fibrous tunica albuginea. The testis is divided into numerous lobules separated by septa, each lobule containing one to three seminiferous tubules within which the spermatozoa are produced by meiosis. The lobules lead to straight ducts that join a plexus, the rete testis, from which 15 to 20 efferent ducts lead to the epididymis. The epididymis leads to the ductus deferens, through which sperm are conveyed to the urethra. Between the seminiferous tubules are the interstitial cells (cells of Leydig), which secrete testosterone. Within the tubules are sustentacular cells, which secrete inhibin. The testes are suspended from the body by the spermatic cord, a structure that extends from the inguinal ring to the testis and contains the ductus deferens, testicular vessels (spermatic artery, vein, lymph vessels), and nerves.


Hyperfunction (hypergonadism) may cause early maturity such as large sexual organs with early functional activity and increased growth of hair. Hypofunction (hypogonadism) is indicated by undeveloped testes, absence of body hair, high-pitched voice, sterility, smooth skin, loss of sexual desire, low metabolism, and eunuchoid or eunuch body type.

descent of testis

The migration of the testis from the abdominal cavity to the scrotum during fetal development.

displaced testis

A testis located abnormally within the inguinal canal or pelvis.

femoral testis

An inguinal testis near or superior to the femoral ring.

inverted testis

A testis reversed in the scrotum so that the epididymis attaches to the anterior instead of the posterior part of the gland.

perineal testis

A testis located in the perineal region outside the scrotum.

undescended testis



The pair of male reproductive glands enclosed in the scrotum that produce the male sex hormone testosterone and the spermatozoa. The singular form is testis.


[L.] plural of testis.

Patient discussion about testes

Q. What is A1C test? My Dr. said I should take it every 4 months or so to see if I kept my diet. what is it exactly..?

A. here’s some on-line info about it:

Q. How do you test for ADHD? Is it a physical test or a psychological test? Or a combination of both?

A. i found a video on youtube about diagnosing AD/HD-

and here is an article about it-

hope it's what you are looking for.

Q. Are there any lab tests used. Are there any lab tests that can be used to diagnose fibromyalgia disease?

A. Yes Liam, there are lots of lab tests to diagnose (or better understand fibromyalgia) but are only used in the research setting. Using them in the clinical setting doesn't help the patient because it doesn't help the problem of not having effective treatments. Many researchers are working on a simple lab test for the office.

More discussions about testes
References in periodicals archive ?
Light microscopy: In the control group, seminiferous tubules and interstitial tissue of testes appeared normal.
Testes and epididymis samples were fixed in 10% formol and dehydrated in 70-100% ethanol series.
Conclusion: Dracaena arborea improves testes morphology and restores spermatogenesis in type 1 diabetic rats, without having major anti-hyperglycemic properties.
Hocking (1992) systematically examined the testes of 378 male Domestic Chickens and found three cases of triorchidism, each of which was comprised of two left testes.
Testes of prepubertal and adult Japanese quail were collected after sacrificing birds and washed in ice-cold normal saline.
The number of non-reproductive cells was also reduced by more than a third in the testes of embryos from smoking mothers.
The scientists compared the number of germ cells - immature cells that become sperm in males and eggs in females - in the testes of embryos from smoking and non-smoking women.
One young male (scrotal testes 3 by 2 mm) was trapped on a branch of a tree.
14-3-3 protein regulates cell adhesion in the seminiferous epithelium of rat testes," Endocrinology 150(10): 4713-4723.
To find out what might cause sperm cells to revert, Matunis's research team genetically altered the flies so that both cells became sperm, reducing the stem cell population in the testes to nothing.
No other focal solid mass was identified in either of the testes.
You could ask your son to examine his testes himself - a good habit to encourage.