Reproduction in Animals Video Lecture | Science & Technology for UPSC CSE

when John sails from two individuals
combined during sexual reproduction a
new individual is formed in simple
organisms two germ cells may be quite
similar to one another
in complex organisms though the germ
cells are more specialized one germ cell
is large and stores food while the other
is smaller and motile this motile germ
cell is the male gamete and the larger
germ cell is the female gamete this
differentiation in germ cells needs the
female and male reproductive organs to
be different this leads to the
similarities in the bodies of male and
female animals
this lesson describes the male and the
female reproductive system in animals
specifically in human beings
it also explains the process of
reproduction and the importance of
reproductive health
at the end of this lesson you will be
able to identify the parts of the male
reproductive system
identify the parts of the female
reproductive system
describe the process of fertilization
and lists various sexually transmitted
diseases
before we begin this lesson let me
introduce you to Eva and spark who broke
I'd you through this lesson
hi I'm spark and I am Eva
all of us know that our bodies change as
we become older
our height increases as we move from one
class to the next
similarly our weight increases as we
grow
these changes make the body become
larger in size in the early teenage ears
of boys and girls
sperm and eggs are formed in the male
and the female reproductive systems
respectively in an unripe state
during this phase a whole new set of
body changes occur that are common to
both boys and girls this may involve
changes in the appearance and proportion
of the body emergence of new features
and the development of new sensations
during this phase boys and girls will
notice hair growth in certain parts of
the body
such as armpits legs face arms and the
genital areas at this time the skin too
frequently becomes oily and might
develop pimples
all these changes take place slowly over
a period of months and years
the time taken for these changes to
occur differs from person to person
these changes are aspects of the sexual
maturity of the body so how do all these
changes link with the reproductive
process or even to our existence as you
know the process of fertilization
involves the fusion of germ cells
but this fusion is possible only once
the male germ cells and the female germ
cells are mature
thus sexual maturity of the body is
necessary for the process of
fertilization to happen during the
teenage phase
growth in the body of the boy and the
girl slows down
in the adolescent phase the reproductive
tissues begin to mature
this period in boys and girls is called
puberty
during this phase of puberty sexual
reproduction in humans is possible but
for that presence of a male reproductive
system and a female reproductive system
similar to the stamen and the carpel in
flowering plants is necessary the sperm
forms a part of the male reproductive
system while the egg forms a part of the
female reproductive system
the male reproductive system consists of
sections that produce germ cells like
sperm while other sections take up the
task of delivering them to the site of
fertilization in males the germ cells
known as sperms are formed in the testes
located outside the abdominal cavity in
the scrotum
these sperms have a long tail that helps
them move towards the female germ cell
but why does this formation happen
outside the abdominal cavity
this is because the sperm formation
requires a lower temperature than the
normal body temperature but the author
of this question is how does sperm end
up meeting the egg if they are placed
somewhere below the abdominal cavity
like I said earlier there are a lot of
organs in the reproductive system that
help sperm to develop and later travel
to meet the egg
let me explain this in detail after the
sperms are formed their development is
regulated by the hormone testosterone
it not only regulates but also helps in
the development of the secondary sexual
character leading to puberty
don't sperms use the help of the vast
difference which joins another tube that
emerges out of the urinary bladder as
the germ cells move along the path of
the vas deferens glands like the
prostate and the seminal vesicles add
their secretions so that these cells
make the transportation easier
don't sperms then pass through the
urethra and through the penis to reach
the female reproductive system where the
sperm gets to meet the egg
what is the wasps deferens used for the
vas deferens continues from epididymis
as a tube
the length of the tube is about 30
centimeters and it is muscular
muscles in the walls helped to propel
the sperm forward
what secretions are made by the glands
the secretions from the seminal vesicle
contain proteins enzymes fructose mucus
vitamin C
Flavin's
phosphoryl Colleen
prostaglandins
the secretion from the prostate gland
comprises simple sugars and is alkaline
in nature the urethra forms a common
passage for both the sperm and urine as
it is just one tube that connects the
glands the bladder and the vas deferens
now let's move over to the female
reproductive system in females germ
cells develop into eggs inside the
ovaries
females are born with a large number of
immature eggs
on puberty these eggs mature and are
responsible for producing some hormones
during puberty some of these eggs start
maturing
every month one egg is produced by one
of the ovaries
this egg is carried from the ovary to
the voom through a tin oviduct also
known as fallopian tube the two oviduct
s-- unites into an elastic bag like
structure known as the uterus
the uterus opens into the vagina through
the cervix
how does fertilization take place
palms enters through the vaginal passage
during sexual intercourse
they then travel upwards and reach the
Obi dock where they get to meet the egg
fertilization takes place here
after fertilization takes place the
fertilized egg also known as the zai cot
starts dividing and gets implanted in
the lining of the uterus as the mother's
body is designed to undertake the
development of the child the uterus
prepares itself by thickening its lining
the uterus is richly supplied with blood
to nourish the growing embryo
the embryo gets nutrition from the
mother's blood
with the help of a special tissue called
placenta
so what is a placenta
and how is it helpful it is a disk which
is embedded in the uterine wall
it contains rely on the embryo side of
the tissue
on the mother's side our blood spaces
which surround the villi
this provides a large surface area for
glucose and oxygen to pass from the
mother to the embryo
the developing embryo will also generate
waste substances which can be removed by
transferring them into the mother's
blood through the placenta
the development of the child inside the
mother's body takes approximately nine
months
the child is born as a result of the
rhythmic contractions of the muscles in
the uterus
now isn't that incredible
this fusion of the sperm and egg has
resulted in the formation of a new life
form
it is not always necessary that the
fusion between the sperm and egg takes
place
however the uterus creates a thick
lining to support the fertilized egg
every month
if the egg does not get fertilized this
lining is not needed and hence it slowly
breaks and comes out through the vagina
as blood and mucus
this cycle takes place roughly every
month and is known as menstruation
it usually lasts for about two to eight
days
all of you may have pressures from
external sources to indulge in sexual
acts or get married and have children
but you must understand the consequences
it may have on your health
a sexual act always has the potential to
cause a pregnancy
pregnancy makes major demands on the
body and the mind of a woman and if
she's not prepared for it
her health may be adversely affected
so how does one void the situation
during intercourse there are some
mechanical barriers that prevent the
sperm from reaching the egg
contraceptive devices like a loop or
copper tee are placed in the uterus to
block the passage of sperm
at the same time contraceptive drugs
could also be taken orally as pills to
avoid pregnancy
since these drunks change the hormonal
balances in the woman they could cause
some side effects like weight gain
depression
vomiting and high blood pressure
apart from contraceptives surgical
methods can also be used to clean blocks
in the man and the woman and to prevent
the transfer of sperm and egg cells
in males the vast difference is blocked
to prevent the passage of sperm
in females the oviduct is blocked to
prevent the passage of eggs
these methods have side effects too
hence it is better to use a condom
during sex that is close contact between
bodies
hence this could result in the
transmission of sexually transmitted
diseases
bacterial infections such as gonorrhea
and syphilis and viral infections such
as warts and HIV or AIDS are some of the
diseases that are transmitted sexually
AIDS a quiet immunodeficiency syndrome
is the infection that is causing havoc
in humans today
using a condom for the male reproductive
organ during sexual intercourse helps
prevent transmission of many of these
infections to some extent
however it feels if it is not used
properly
[Music]
[Applause]
[Music]
[Applause]
you
[Music]
[Applause]
[Music]
you
[Music]
you