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The man-From a small seed
Male reproduction system is made up of two
separate parts,the one which is responsible
for secreting male sexual hormone , and the
other one that produces sperms . The major
organs of the male reproductive system are
the testes,the prostat,the seminal vesicles,
the vas deferens , the epididymis and the
penis. Male sexual hormone ) testosterone )
is secreted inside the testicle by the cells
which are scattered through the seminiferous
tubes,and also by known as Leydic cells.
There are also other male hormones which are
secreted by adrenal gland and have lesser
power . These hormones cause masculine
characteristics.
The part responsible for the production
of sperm , produces male sexual cells
or Spermatozoa . The internal wall of
the seminiferous tubes is covered with
a number of cells called Germ cells .
After growing enough these cells develop
into Spermatogonium. During the meiosis,
cell division ) in which the number of
chromosomes are decreased into half )
each of these cells are divided into four
Spermatides,each of which contain twenty
three chromosomes ) half of the chromosomes
in non-reproductive cells (. Spermatides
are then transformed into Spermatozoa. Each
spermatozoon contains a round or enlongated
head,body,and a long tail-like structure
used for movement. The head carries genetic
information of the father , and in case the
sperm is mixed with ovum , this information
along with the genetic information from the
ovum are used to form the baby.A thin layer
covers the head of spermatozoon . In this
layer there are special enzyme system which
help the process of sperm penetration into
the ovum.
The spermatozoa,the secretions from the semen
vesticle and the prostate gland altogether
make the semen , which is a nourishing and
suitable environment for sperms to live in.
During the process of ejaculation spermatozoa
which are suspended in the semen are come out
of man's genital organ . These sperms do not
have the reproductive ability immediately and
must stay a few hours in women's genital
system until they are ready for reproduction.
This activation of sperms is called
Capacitation.It should be mentioned that only
sperms,but not the semen,enter the uterus and
fallopian tubes.
The movement of spermatozoa inside the
genital system of women happens throug
two mechanisms :
1 - actively,hence with the help of it own
tail movement spermatozoa can move a few
millimeters forward in a minute.
2 - inactively , through the regular
contraction of the muscles of the uterus.
During every ejaculation a few milliliters
of semen,containing millions of spermatozoa,
leave man's genital organ . This number of
spermatozoa is for the certainty of
fertilization.
Spermatozoa usually retain their reproductive
ability for twenty four hours . Although
spermatozoa may remain active for a longer
period,with time they gradually lose their
ability for reproductivity ; and usually
reproduction by old sperms is not possible
and in case it happens unwelcomed
consequences is to be expected during the
formation of the offspring.
