…the release of the hormone testosterone, which causes growth of the internal and external genitalia, development of pubic, axillary, and facial hair, changes in the larynx that result in deepening of the voice, and increased statural growth and muscular development.

Many vertebrate brain structures involved in the control of aggression are richly supplied with receptors that bind with hormones produced in the endocrine system, in particular with steroid hormones produced by the gonads. It provides negative feedback inhibition on the secretion of gonadotropin-releasing hormone from the hypothalamus and the secretion of luteinizing hormone from the pituitary gland. Similar to other steroid hormones, testosterone exists in serum in two forms. Be on the lookout for your Britannica newsletter to get trusted stories delivered right to your inbox. Testosterone is a hormone produced by the human body.

Testosterone is produced mainly in the testes and is also used as a drug in the treatment of certain medical disorders. Testosterone, hormone produced by the male testis that is responsible for development of the male sex organs and masculine characteristics, including facial hair and deepening of the voice.

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Learn more about testosterone in this article. (figuratively) Manly behavior, often of an aggressive or foolishly reckless nature.

Low testosterone: Abnormally low levels of the male sex hormone testosterone in the blood. By signing up for this email, you are agreeing to news, offers, and information from Encyclopaedia Britannica. Testosterone is a hormone found in men and male animals, which can also be produced artificially. This information should not be considered complete, up to date, and is not intended to be used in place of a visit, consultation, or advice of a legal, medical, or any other professional. Using testosterone for these purposes may be harmful to your health. https://www.thefreedictionary.com/testosterone, (Biochemistry) a potent steroid hormone secreted mainly by the testes.

Testosterone can be manufactured by chemical and microbiological modification of inexpensive steroids, such as diosgenin. Most testosterone in the serum is bound to sex hormone-binding globulin and to albumin, while the remaining amount (about 1 percent) is free, or unbound.

testosterone definition: a steroidal male sex hormone, CHO, produced as a white, crystalline substance by isolation from animal testes, or synthesized: used in medicineOrigin of testosterone test(is) + -o- …

The main sources of testosterone in the body are the testes. Testosterone, hormone produced by the male testis that is responsible for development of the male sex organs and masculine characteristics, including facial hair and deepening of the voice. Define testosterone.

Free testosterone is in equilibrium with bound testosterone so that when free testosterone enters cells, some bound testosterone is immediately freed. Testosterone is also converted to estradiol in adipose tissue (and to a lesser extent in some other tissues), which is the most important source of estrogen in men. People will see it as Author Name with your public flash cards.

Testosterone is produced by the testes and to a lesser extent by the adrenal glands.

It is thought to be responsible for the male sexual instinct and other male characteristics. testosterone meaning: 1. a male hormone that causes a stage of growth in older boys and development of their sexual…. It also directs the development of the embryonic Wolffian ducts into the vas deferens (ductus deferens) and seminal vesicles and stimulates the formation of muscle and bone. All rights reserved. and All content on this website, including dictionary, thesaurus, literature, geography, and other reference data is for informational purposes only. Privacy Policy.

testosterone synonyms, testosterone pronunciation, testosterone translation, English dictionary definition of testosterone. Testosterone therapy is only recommended for hypogonadism patients. Published by Houghton Mifflin Harcourt Publishing Company. Checking testosterone levels is as easy as having a blood test.

It can be extracted from the testes of animals or synthesized and used to treat androgen deficiency or promote anabolism. "There is limited evidence on the long-term clinical benefits of [testosterone therapy] to effectively treat the modestly declining levels of [natural], Early hormone researchers were fixated on sexual anatomy and reproduction, they gave short shrift to, "There certainly are going to be patients in the 65-plus age range in whom, Because men do not go through a well-defined period referred to as menopause, some doctors refer to this problem as androgen (, The two can be distinguished by elevated gonadotropin levels (LH and FSH) in primary hypogonadism, which rise in response to low, Historically, the efficacy of androgen-deprivation therapies (ADT) has been assessed by measuring levels of circulating, Dictionary, Encyclopedia and Thesaurus - The Free Dictionary, the webmaster's page for free fun content, Testosterone Therapy May Threaten the Heart, Testosterone slows prostate cancer recurrence in low-risk patients, Do You Really Need a Testosterone Boost?

Testosterone is converted to dihydrotestosterone in most tissues that are sensitive to androgens, including the testes, prostate gland, hair follicles, and muscles. Testosterone is the primary sex hormone and anabolic steroid in males. The American Heritage Dictionary of Medicine © 2018 by Houghton Mifflin Harcourt Publishing Company. Please set a username for yourself. Copyright © 2016, 2011 by Houghton Mifflin Harcourt Publishing Company. Our editors will review what you’ve submitted and determine whether to revise the article. Learn more. However, testosterone proved to be more potent than androsterone, which was later shown to be a biochemical product (a metabolite) of testosterone.

Testosterone is so much more than its reputation would suggest.

Dihydrotestosterone is responsible for sperm maturation during spermatogenesis, for the formation of the prostate gland and external genitalia, and for sexual maturation at puberty. Testosterone is the most important of the hormones known as androgens. Although testosterone itself has androgenic actions, its conversion to dihydrotestosterone is critical to the development of external genitalia in boys. >testosterone and its derivatives, the anabolic steroids. a steroidal male sex hormone, CHO, produced as a white, crystalline substance by isolation from animal testes, or synthesized: used in medicine. Webster's New World College Dictionary, Fifth Edition Copyright © 2014 by Houghton Mifflin Harcourt Publishing Company. Get exclusive access to content from our 1768 First Edition with your subscription. However, the optimal amount of testosterone is far from clear. n. 1. English Wiktionary. Formula: C19H28O2. It is used clinically to treat testicular insufficiency, to suppress lactation (milk production), and to treat certain types of breast cancer. THE AMERICAN HERITAGE® DICTIONARY OF THE ENGLISH LANGUAGE, FIFTH EDITION by the Editors of the American Heritage Dictionaries. The men's faithful companion. Available under CC-BY-SA license. A steroid hormone that regulates the development of the male reproductive system and male secondary sex characteristics.

Clinical Professor of Medicine, Harvard Medical School.

Men and women need the proper amount of testosterone to develop and function normally. When production of testosterone drops or ceases, a … Any of several synthetic compounds that mimic the physiologic activity of testosterone, used as drugs in the medical treatment of testosterone deficiency and as doping agents by athletes.
Testosterone has several major actions.

Furthermore, testosterone is interconvertible with androstenedione, which can be converted into estrogens.

In about half of all boys, noticeable swelling of mammary-gland….

Confirm low T readings and identify the source of your symptoms before starting treatment, Low sexual desire: Appropriate use of testosterone in menopausal women, SHBG and FAI are valuable tools in the diagnosis of androgen status, Testosterone therapy in men with hypogonadism, Looking for Mr. T.: the pros--and con--of testosterone, Testosterone monitoring for men with advanced prostate cancer: Review of current practices and a survey of Canadian physicians, Testosterone-repressed Prostate Message 2. Testosterone was isolated from testicular extracts in 1935.

When androstenedione is formed in adipose tissue, it may be converted to a form of estrogen called estrone. By continuing, you agree to our Its discovery followed that of an androgen (male hormone) called androsterone, which was isolated from urine in 1931. The difficult part is interpreting the result.

In male humans, testosterone plays a key role in the development of male reproductive tissues such as testes and prostate, as well as promoting secondary sexual characteristics such as increased muscle and bone mass, and the growth of body hair.

All rights reserved. Testosterone serves as a circulating prohormone for a more active androgen called dihydrotestosterone. Testosterone was isolated from testicular extracts in 1935. All rights reserved. Get kids back-to-school ready with Expedition: Learn. In the cytoplasm of target cells, testosterone or dihydrotestosterone binds to specific androgen receptors, and the hormone-receptor complexes enter the cell nucleus, where they modulate protein synthesis by influencing the rate at which particular genes are transcribed (see transcription). In a wide range of vertebrate species, there is a clear….