Hi julio123,
The Male Reproduction System is where testosterone is produced. The
testes are two egg-shaped male reproductive organs located in the
scrotum. They produce sperm and the male hormone, testosterone.
In males, 95% of the testosterone is secreted by the testicles, with a
small amount of 5% also coming from the adrenal glands. In the male
body, testosterone is the most important sex hormone. Testosterone is
responsible for development of male characteristics such as body and
facial hair, muscle growth and strength, and a deep voice. Normal
levels of testosterone also influence the production of sperm, promote
sexual function and promote sex drive. The testes are located inside
the scrotum,which hangs below (at the base of) the penis. The scrotum
is like a bag or sac of skin that holds the testes or testicles where
sperm are made from puberty to old age. The skin of the scrotum is a
bit hairy and oily.
The scrotum and testicles will change their appearance which is
entirely normal. The scrotum is a loose, wrinkly bag of skin that
contains the two testicles (testes, 'balls'). During puberty the
testicles will grow in size.
===============================================================================
The Testicles
http://www.addenbrookes.org.uk/shac/normal/male/ma_anat.html
What are the genitals?
"The genitals include the penis, scrotum and testicles (see the diagram below)."
[edit]
"What are the scrotum and testicles, and why do they change their appearance?
At the base of the penis is the scrotum. This is a loose, wrinkly bag
of skin that contains the two testicles (testes, 'balls'). It is
usually darker than the skin of the penis and is slightly hairy. You
have a scrotum because the testicles produce healthier sperm when they
are kept at a lower temperature than that of the rest of the body.
When it is cold, the scrotum gets even more wrinkly. When it is warm,
the testicles hang more loosely and the skin of the scrotum becomes
smooth. During sex, the testicles can move up into the body and might
almost seem to have disappeared this can sometimes be a bit
uncomfortable but is quite normal. During puberty, the testicles grow
in size."
===============================================================================
Anatomy of the Adrenal Glands - see diagram
http://www.endocrinesurgeon.co.uk/adrenals/adrenals1-2.html
"The two adrenal glands (also called the suprarenal glands) are
situated in the abdomen, above the kidneys and below the diaphragm."
===============================================================================
MALE REPRODUCTIVE ORGANS - Testosterone - the primary male sex hormone
http://www.fertilitext.org/p4_male/the_male_body.html
The testes (two testicles) are located within the scrotal sac, an
external pouch of skin found below the man's penis. In addition to
sperm, the testes produce testosterone, a male hormone that is largely
responsible for defining and maintaining "male" characteristics. Once
produced, sperm pass from the testes through to the epididymis in
order to mature.
(see diagram middle of the page)
===============================================================================
MEN'S HEALTH - testosterone and male sexual behaviour
http://www.tiscali.co.uk/lifestyle/healthfitness/menshealth/part1_7-1.html
TESTOSTERONE AND ITS IMPORTANCE
"Testosterone is the most important androgen, or male sex hormone. In
males, 95 per cent is secreted by the testicles, with a small amount
(5 per cent) also coming from the adrenal glands. A mature male
secretes between 4 and 10 mg of testosterone per day. In females,
small amounts of testosterone are also secreted by the adrenal glands
and ovaries."
===============================================================================
What Are Hormones?
http://128.121.138.75/hormones.html
"A hormone is a chemical messenger which helps cells communicate with
each other in the body. Hormones help regulate many functions of the
body's systems and organs."
Click on testis and ovaries - (which are the gonads) - and adrenals
for individual hormone for details.
Gonads
Testis
Testosterone
"A steroid hormone synthesized mostly by the testes in males and by
the ovaries in females as well as the adrenal glands of both sexes.
Testosterone is synthesized from androstenedione, a metabolite of DHEA
and progesterone, the precursors being pregnenolone and cholesterol.
Estradiol
The most potent of the estrogen steroids. Long bones, development of
breasts, reproductive organs and secondary female characteristics are
the responsibility of estradiol. It is mainly produced by the ovaries.
It is also produced by the adrenal glands and by the precursors
converting into estrogen in fatty tissue.
Androstenedione
Androgens (male hormone) are produced in two sites in the male body.
Most originate in the testes, but some potent male hormones are
produced by the adrenal glands, located just above the kidneys.
Androstenedione is a pivotal adrenal steroid that's actually one step
closer to being converted to testosterone than DHEA."
Ovary
[edit]
Testosterone
"A steroid hormone synthesized mostly by the testes in males and by
the ovaries in females as well as the adrenal glands of both sexes.
Testosterone is synthesized from androstenedione, a metabolite of DHEA
and progesterone, the precursors being pregnenolone and cholesterol."
===============================================================================
http://www.mytestosterone.com/files/glossary.html?#Testosterone
Testosterone - the male sex hormone in the body that stimulates key
processes, including: increases in muscle mass and strength,
development of facial and pubic hair, enlargement of the voice box and
deepening of the voice, increased size of the penis and testes, change
in body shape, maintenance of sex drive and sperm cell production. It
may also play a role in maintaining energy and mood.
===============================================================================
Allrefer.com Health
http://health.allrefer.com/health/testes-info.html
Testes - Alternate Names: Gonads - Male, Testicles, Testis
===============================================================================
Click here for the Anatomy imgage
http://health.allrefer.com/health/testes-male-reproductive-anatomy.html
===============================================================================
Testosterone
http://www.explainplease.com/testosterone.htm
"Testosterone is a steroid hormone from the androgen group. Its main
function is as the male sex hormone. It is secreted by the testes, but
is also synthesized in small quantities in the ovaries, cortices of
the adrenal glands, and placenta, usually from cholesterol.
In the testes testosterone is produced by the Leydig cells. Due to
dual function of the male gonad testosterone directly influences
spermatogenesis. Transport of testosterone is performed by specific
sex hormone binding globulin (SHBG) that is found in the plasma. Then
in the target tissues transformation of testosterone into 2.5 times
more potent form 5a-dihydrotestosterone is carried out. The sequence
of actions is needed for the hormone to exert its physiological role.
First it binds to steroid hormone receptors located in the cytosol and
the nucleus. These receptors are ligand-activated and in effect they
undergo structural change that renders them capable of binding to
specific nucleotide sequences in the DNA called hormone response
elements (HREs). While bound they influence transcriptional activity
of certain genes.
Testosterone was first isolated from a bull in 1935. Pharmaceutical
products derived from testosterone have been used for a rather diverse
range of indications: male infertility, athletic enhancement, libido
problems, erectile dysfunction, prevention of osteoporosis caused by a
lack of androgens. Real testosterone deficiency is rare and the
indications for use must be chosen prudently."
Male fetuses need testosterone for the development of male external
genitalia, and at puberty in males an increase in testosterone level
causes further growth..."
===============================================================================
Google search:
testosterone male body produces
testis
testicals
adrenal glands
androgen
scrotum
Best regards,
tlspiegel |
