The Male Reproductive System
The organs of the male reproductive system are specialized for the following functions:
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To produce, maintain and transport sperm (the male reproductive cells) and
protective fluid (semen)
To discharge sperm within the female reproductive tract
To produce and secrete male sex hormones
The human male reproductive system (or male genital system) consists of a number of
sex organs that are a part of the human reproductive process. These sex organs are located
outside the body, around the pelvic region.
The main anatomically male sex organs are the penis and the testes which produce semen
and sperm, which as part of sexual intercourse fertilize an ovum in an anatomically female
person's body and the fertilized ovum (zygote) gradually develops into a fetus, which is
later born as a child.
The male reproductive anatomy includes internal and external structures.
What are the external reproductive structures?
Most of the male reproductive system is located outside of the man’s body. The external
structures of the male reproductive system are the penis, the scrotum and the testicles.
Penis — The penis is the male organ for sexual intercourse. It has three parts: the root,
which attaches to the wall of the abdomen; the body, or shaft; and the glans, which is the
cone-shaped end of the penis. The glans, also is called the head of the penis, is covered
with a loose layer of skin called foreskin. (This skin is sometimes removed in a procedure
called circumcision.) The opening of the urethra, the tube that transports semen and urine,
is at the tip of the glans. The penis also contains a number of sensitive nerve endings.
The body of the penis is cylindrical and consists of three internal chambers. These are made
up of special, sponge-like erectile tissue. This tissue contains thousands of large spaces
that fill with blood when the man is sexually aroused. As the penis fills with blood, it
becomes rigid and erect, which allows penetration during sexual intercourse.
Testicles (testes) — The testes are oval organs about the size of large olives that lie in the
scrotum, secured at either end by the spermatic cord. Most men have two testes.
The testes are responsible for making s, the primary male sex hormone, and for generating
sperm..
Epididymis – It is a long, coiled tube that rests on the backside of each testicle. It functions
in the transport and storage of the sperm cells that are produced in the testes. It also brings
the sperm to maturity, since the sperm that emerges from the testes are immature and
incapable of fertilization. During sexual arousal, contractions force the sperm into the vas
deferens.
What are the internal reproductive organs?
The internal organs of the male reproductive system include the following:
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Vas deferens — The vas deferens is a long, muscular tube that travels from the
epididymis into the pelvic cavity, to just behind the bladder. The vas deferens
transports mature sperm to the urethra in preparation for ejaculation.
Ejaculatory ducts — These are formed by the fusion of the vas deferens and the
seminal vesicles. The ejaculatory ducts empty into the urethra.
Urethra — The urethra is the tube that carries urine from the bladder to outside of
the body. In males, it has the additional function of expelling (ejaculating) semen
when the man reaches orgasm. When the penis is erect during sex, the flow of urine
is blocked from the urethra, allowing only semen to be ejaculated at orgasm.
Seminal vesicles — The seminal vesicles are sac-like pouches that attach to the vas
deferens near the base of the bladder. The seminal vesicles produce a sugar-rich
fluid (fructose) that provides sperm with a source of energy and helps with the
sperms’ motility (ability to move). The fluid of the seminal vesicles makes up most
of the volume of a man’s ejaculatory fluid, or ejaculate.
Prostate gland — The prostate gland is a walnut-sized structure that is located
below the urinary bladder in front of the rectum. The prostate gland contributes
additional fluid to the ejaculate. Prostate fluids also help to nourish the sperm. The
urethra, which carries the ejaculate to be expelled during orgasm, runs through the
center of the prostate gland.
Bulbourethral glands — The bulbourethral glands, or Cowper’s glands, are peasized structures located on the sides of the urethra just below the prostate gland.
These glands produce a clear, slippery fluid that empties directly into the urethra.
This fluid serves to lubricate the urethra and to neutralize any acidity that may be
present due to residual drops of urine in the urethra.
How does the male reproductive system function?
The entire male reproductive system is dependent on hormones, which are chemicals that
stimulate or regulate the activity of cells or organs. The primary hormones involved in the
functioning of the male reproductive system are follicle-stimulating hormone (FSH),
luteinizing hormone (LH) and testosterone.
FSH and LH are produced by the pituitary gland located at the base of the brain. FSH is
necessary for sperm production (spermatogenesis), and LH stimulates the production of
testosterone, which is necessary to continue the process of spermatogenesis. Testosterone
also is important in the development of male characteristics, including muscle mass and
strength, fat distribution, bone mass .
The human female reproductive system (or female genital system)
Contains two main parts:
the uterus: hosts the developing fetus, produces vaginal and uterine secretions, and passes
male's sperm through to the fallopian tubes
the ovaries: produce the female egg cells. These parts are internal; the vagina meets the
external organs at the vulva, which includes the labia, clitoris and urethra. The vagina is
attached to the uterus through the cervix, while the uterus is attached to the ovaries via the
Fallopian tubes. At certain intervals, the ovaries release an ovum, which passes through the
Fallopian tube into the uterus.
If, in this transit, it meets with sperm, the sperm penetrate and merge with the egg,
fertilizing it. The fertilization usually occurs in the oviducts, but can happen in the uterus
itself. The zygote then implants itself in the wall of the uterus, where it begins the processes
of embryogenesis and morphogenesis. When developed enough to survive outside the
womb, the cervix dilates and contractions of the uterus propel the fetus through the birth
canal, which is the vagina.
The ova are larger than sperm . Approximately every month, one ovum is sent down the
Fallopian tube attached to its ovary in anticipation of fertilization. If not fertilized, this egg
is flushed out of the system through menstruation.
The internal reproductive organs are the vagina, uterus, fallopian tubes, cervix and ovary.
Vagina
The vagina is a fibro muscular tubular tract leading from the uterus to the exterior of the
body in female mammals. The vagina is the place where semen from male is deposited into
female body .
Cervix
The cervix is the lower, narrow portion of the uterus where it joins with the top end of the
vagina. The vagina has a thick layer outside and it is the opening where the baby emerges
during delivery. The cervix is also called the neck of the uterus.
Uterus
The uterus or womb is the major female
reproductive organ of humans. The uterus
provides mechanical protection, nutritional
support, and waste removal for the
developing embryo (weeks 1 to 8) and
fetus (from week 9 until the delivery). In
addition, contractions in the muscular wall
of the uterus are important in pushing out
the fetus at the time of birth.
The uterus is a pear-shaped muscular
organ. Its major function is to accept a
fertilized ovum which becomes implanted
into the endometrium, and derives nourishment from blood vessels which develop
exclusively for this purpose.
Oviducts
The Fallopian tubes or oviducts are two tubes leading from the ovaries of female
mammals into the uterus.
On maturity of an ovum, the follicle and the ovary's wall rupture, allowing the ovum to
escape and enter the Fallopian tube. There it travels toward the uterus. This trip takes hours
or days.
Ovaries
The ovaries are small, paired organs that are located near the lateral walls of the pelvic
cavity. These organs are responsible for the production of the ova and the secretion of
hormones. The process by which the ovum is released is called ovulation
QUESTIONAIRE—8TH GRADE
Explain the two functions of the urethra.
What are the hormones involved in the male reproductive system?
What male characteristics does testoterone develop?
What is the male foreskin?
What is the ovum?
What is a zygote?
What happens when the ovum comes through the Fallopian tubes and meets with sperm at
the uterus?
What happens when the ovum comes through the fallopian tubes and does not meet with
sperm?
What does uterus provide to the embryo?
Project
40
Exam
30
Class questionaire 15
Cross words
15
vagina
where baby is delivered
penis
male reproductive organ
uterus
where embryo develops
ovaries
produce ovums
fallopian
tubes that carry ovums to the uterus
testoterone
male hormoneglans
urethra
expells urine and semen
testes
produce hormones and sperm
head of penis
womb
uterus
epidydimis
transports and stores semen
scrotum
skin around the penis
foreskin
skin on the glans
menstruation
unfertilized egg flushed out.
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ACROSS
DOWN
3. where fetus develops
4. tube that expells urine and semen
6. where baby isdelivered
1. male reproductive organ
2. produce hormones and sperm
5. where ovum is produced
7. male hormone
9. oviducts
8. head of penis
11. skin around testes
10. where sperm is matured
12. skin around glans
13. unfertilized egg flushed out.
14. uterus
15. Tubes through which the ovum moves
to uterus
.