Download HOW DO ORGANISMS REPRODUCE

HOW DO ORGANISMS REPRODUCE
Reproduction
It is the formation of new similar young living organisms by
the existing or grown up organisms of a species or race. In
simple words reproduction is the creation of new living
organisms. Reproduction is essential for the survival of a
species because all living organisms grow old with time and
ultimately die after surviving for a limited period of time. So,
living organisms produce more organisms of their kind so as to
maintain the life of their species on this earth. If however,
some species of the living organisms cannot reproduce due to
certain reasons, then the organisms of those species will
gradually die out and disappear from this earth one day.
Do Organisms Create Exact Copies Of Themselves?
A basic event in reproduction is the creation of DNA copy. Cells
use chemical reactions to build copies of their DNA. This
creates two copies of the DNA in a reproducing cell and they
will need to be separated from each other. DNA copying is also
accompanied by the creation of additional cellular apparatus
and then the DNA copies separate, each with its own cellular
apparatus. No biochemical reaction is absolutely reliable;
therefore the process of copying of DNA will have some
variations each time. Thus the exact copies will not be created.
This inbuilt tendency for variation during reproduction is the
basis for evolution.
Note
Variation is useful for the survival of species over time.
That is why existence of variations is very important.
Types Of Reproduction
Methods of reproduction are mainly divided in two groups: 1. Asexual Reproduction
2. Sexual Reproduction
1. Fission
It is a type of asexual reproduction in which the parent
organism splits to form two or more new organisms.
Types Of Fission
(i) Binary Fission
In binary fission the parent organism splits to form two new
organisms. When this happens, the parent organism ceases
(stops) to exist and two new organisms come into existence.
Example
The unicellular organisms like planaria (flatworm), amoeba,
euglena, paramecium, bacteria etc. A fully grown paramecium
divides its body into two parts to form two smaller paramecia.
First the nucleus of the parent paramecium divides followed by
the division of cytoplasm and two small paramecia are
produced. Then these two grow to their full size and split
again to produce four new paramecia. And this process of
reproduction is repeated again and again giving rise to their
population.
Binary Fission In Amoeba
1. Asexual Reproduction
In asexual reproduction the new organism is produced from
single parent without the formation and fusion of gametes. In
asexual reproduction method certain body cells of the parent
organism undergo repeated mitotic cell divisions to form two
or more new organisms of the same kind.
Binary Fission In Euglena
Characteristics Of Asexual Reproduction
1. Cell division through mitosis only.
2. Genetic similarity among parent and young ones.
3. Rapidity and absence of haploid, diploid alteration.
Different Methods Of Asexual Reproduction
1.
2.
3.
4.
5.
6.
Fission
(i) Binary Fission
(ii) Multiple Fission
Budding
Regeneration
Fragmentation
Spore Formation
Vegetative Propagation
(ii) Multiple Fission
In multiple fission, parent organism splits to form many new
organisms at the same time. During multiple fission nucleus of
parent cell divides into many nuclei. Each nucleus gets
surrounded by a bit of cytoplasm and forms daughter cells. As
many daughter cells are formed from a single parent cell as
the number of daughter nuclei produced by the division of
parent nucleus. When the favourable conditions arrive, then
the cyst breaks open and many daughter cells present in it are
released, each forming a new organism.
Example
Plasmodium reproduces by multiple fission.
2. Budding
In budding a small part of the body of the parent organism
grows out as a bud, which then detaches and becomes a new
organism. Budding is observed in hydra and yeast. Budding
may occur in multicellular as well as unicellular organisms.
Example
In yeast a little cytoplasm gets accumulated at one end of the
cell and forms a bud, on the outside of the cell wall. The
nucleus of parent cell then divides into two parts and one part
enters into the bud. Ultimately the bud separates off from the
parent yeast cell and forms a new yeast cell. In yeast, bud
formation is very fast thus in short time a chain of yeast cells
is produced. After some time all the yeast cells of the chain
separate from one another and form individual yeast plants.
4. Fragmentation (Special Case Of Regeneration)
The natural breaking up of a multicellular organism into two or
more parts each of which grows to form a new organism is
called fragmentation. Fragmentation is a special case of
regeneration in which a parent multicellular organism on
maturing breaks up naturally to produce two or more daughter
organisms. For example, spirogyra and alga plant breaks up
into two or more fragments on maturity and each fragment
grows into new spirogyra.
Budding In Hydra
Difference Between Fission And Fragmentation
In fission a unicellular organism breaks up to form two or
more daughter organisms whereas in fragmentation a
multicellular organisms breaks to form multiple new daughter
organisms.
3. Regeneration
Regeneration is the ability of the organisms to replace their
lost parts or we can say that the process of getting back full
organism from its body parts is called regeneration. If the
individual is somehow cut or broken into many pieces, many of
these grow into separate individuals. In some plants as well as
animals small cut parts of their body can grow to form whole
new organism complete in all the respects. Regeneration is
carried out by specialized cells. These cells multiply and make
large number of cells. From this mass of cells, different cells
undergo changes to become various cell types and tissues.
5. Spore Formation
Formation of new organisms from the tiny spores produced by
parent plant in hundreds of number is called spore formation.
Spores are tiny spherical unicellular structures protected by a
thick wall, are formed under unfavourable conditions. They
grow into a new plant when conditions are favourable.
Example
Bread mould (rhizopus), mucor (pin mould), penicillium (blue
green worm) and bacteria reproduce by the method of spore
formation.
Example
Animals like hydra, planaria (flatworm), spirogyra and sponges
show regeneration.
It happens as follows: During the growth of a fungus plant, tiny round, blob like
structures called sporangia develop at the top of the erect
hyphae, which are called sporangiophores. In the sporangium
nucleus divides several times and each part of nucleus along
with a bit of cytoplasm develops into a spore. When the
sporangium bursts then the spores spread into air. When these
air borne spores land on food under favourable conditions like
moisture and warmth, they germinate to form new fungus
plants. At first they look like a white cottony mass covering
which later on turns black. The tiny spores of rhizopus are
present in air around us.
6.
6. Vegetative Propagation
In vegetative propagation new plants are obtained from the
parts of old plants like stems, roots and leaves without the
help of any reproductive organs. It involves the growth and
development of one or more buds present on the old part of
plant to form a new plant. Theses buds are in inactive state in
the old part of plant. In suitable conditions these buds grow to
form new plants. There are two ways of vegetative
propagation or vegetative reproduction.
2. Sexual Reproduction
(i) Natural Vegetative Propagation
(ii) Artificial Vegetation Propagation
(i) Natural Vegetation Propagation
In this method various plant structures take part like roots,
stem, leaves and bud.
By Roots
Some plants like reddish, sweet potato, danlia, carrot etc
reproduce by roots.
By Stems
Some plants reproduce by means of stems. They may be
aerial like runners, suckers or underground like ginger,
potato and onion.
By Leaves
Some plants have ability to reproduce from the leaves.
The buds are formed on the leaf margin and give rise to
new plants like that in Bryophyllum. The new plants
remain attached to the leaf for some time and then are
detached and grow into an independent plant.
Advantages Of Artificial Vegetative Propagation
1. The new plants produced by artificial vegetative propagation
will be exactly like the parent plants. Any desirable feature
of the parent plant will be replicated in the new plants.
2. The fruit trees grown from seeds may take many years
before they start to bear fruit but the fruit trees grown
from cuttings or by grafting start to bear fruits much
earlier.
3. The plants grown by vegetative propagation usually need
less attention in their early years than the plants grown
from seeds.
4. Disease free plants can be produced.
5. It is the only method of reproduction for those plants
which do not produce seeds.
It is easier, cheaper and quicker method.
Tissue Culture (Micro propagation)
The production of new plants from isolated plant cells or small
pieces of plant tissue in a synthetic medium called culture
solution is called micro propagation or tissue culture. The
medium used for growing plant cells is very important in this
process because it contains various plant nutrients and plant
hormones which are necessary for growth of plant.
Sexual Reproduction involves the existence of two sexes, each
contributing a gamete (mature sex cell) formed after meiosis,
for the formation of the new individual after fertilization.
Meiosis reduces the number of chromosomes in the gametes
by half. Thus the fusion of male and female gametes results in
a diploid new individual. First diploid cell formed after fusion is
known as zygote which later divides mitotically to form
complete new individual. During meiotic division, genetic
material contained in the chromosomes gets mixed between
homologous chromosomes. This results in new combinations
of genetic material and accounts for the uniqueness of
individual.
Sexual Reproduction In Plants
Sexual Reproduction in plants takes place through flowers.
Like humans plants also have male and female sex organs,
though they are different from humans. In most plants the
same flower contains the male as well as female organs. The
majority of plants are bisexual having the male and female
reproduction organs in the same plant or same flower
(hermaphrodites). The function of the flower is to make male
and female gametes and to ensure that fertilization will take
place to make new seeds for the reproduction of plants.
Structure Of A Flower
Pedicel
The stalk of flower is known as pedicel.
Receptacle
The broadened base of flower which lies at the tip of pedicel is
called thalamus. At this point all parts of a flower are
attached. It is also called receptacle.
Sepals
The green leaf like parts in the outer most circle of a flower is
called sepal. In some plants it may be colored to attract
insects. It protects the flower especially in bud conditions.
Calyx
All sepals taken together are called calyx. It is the outermost
series of green non essential floral organs.
Petals
The colourful parts of a flower are called petals. They attract
various insects and animals for pollination.
Perianth
If both sepals and petals are coloured and cannot be
distinguished from each other then their whorl (circle) is
known as perianth and its constituents are known as tepals.
Stamen (Androecium)
Stamen is the male reproductive organs in plant. These are
little stalks with swollen tops just inside the ring of petals in a
flower. The stamen is made up of two parts: 1. Filament
Stalk of stamen.
2.
Anther
Upper sac like structure is known as anther. Anther is
made up of two anther lobes which further contain
two pollen sacs. Pollen sacs contain pollen grains.
The pollen grains appear to be yellow powder like
substance to us. Pollen grains contain the male
gametes of the plant. Each pollen grain contains two
male gametes of the plants. There are many stamens
in the flowers.
Carpel (Pistil, Gynoecium)
Carpel is the female reproductive organ of flower. A carpel is
made up of three parts: 1. Stigma
The top part of carpel is called stigma. Stigma is for
receiving the pollen grains from anther of stamen
during pollination.
2. Style
The middle part of carpel is called style. Style is a
tube which connects stigma to the ovary.
3. Ovary
The swollen part at the bottom of a carpel is called
ovary. The ovary makes ovules and stores them.
Ovules contain female gametes of the plant. There
are many ovules in the ovary. Each ovule contains
only one female gamete of the plant. The female
gamete present inside ovule is called ovum or egg.
Formation Of Seeds
A seed of plant is formed when the male gamete present in
the pollen grain fuses with female gamete present in ovule.
Formation of seeds occurs in two steps: 1. Pollination
2. Fertilization
Pollination
The transfer of pollen grains from the anther of a stamen to
the stigma of a carpel is called pollination.
Types Of pollination
1. Self Pollination
Pollination between same flower or flowers of same plant is
called self pollination.
(i) Autogamy
It is the pollination in the same flower.
(ii) Geitonogamy
It is the pollination between different flowers of the same
plant.
2. Cross Pollination (Xenogamy)
It is the pollination between the flowers of different plants.
Transfer of pollen grains can take place by various ways: (i) Wind Pollination
(ii) Insect Pollination
(iii) Water Pollination
(iv) Bird Pollination
(v) Bat Pollination
As geitonogamy resembles cross pollination in the requirement
of pollen transfer or pollinating agency, both xenogamy and
geitonogamy are included under allogamy though this term is
most commonly used for cross pollination.
Pollen Grain (Microspore)
A pollen grain is rounded in outline. Internally it has: 1. Tube or vegetative cells with degenerating nucleus.
2. Vacuolated cytoplasm rich in starch and unsaturated oils.
3. One generative cell or two male gametes derived from it.
Embryo Sac
Each ovule inside the ovary of a flower consists of a large oval
shaped cell called embryo sac. It is the female gametophyte.
The embryo sac is surrounded by two protective membranes.
The embryo sac grows and its nucleus undergoes repeated
mitotic divisions until eight nuclei are produced. Thus a mature
embryo contains eight nuclei out of which one is female
gamete called ovule. The eight nuclei of embryo sac are
present in groups of four nuclei at the opposite poles of
embryo sac. The embryo sac has a small opening at its one
end, which is called micropyle. Through micropyle the male
gametes through pollen tubes enter into embryo sac. An
embryo sac is seven celled and 8 nucleate structures. Three
micropylar cells contain three micropylar nuclei. Three chalazal
cells contain 3 chalazal nuclei. One central cell contains two
polar nuclei.
2. Fertilization
When a pollen grain falls on the stigma of the carpel. It grows
a pollen tube downward in the style. This pollen tube contains
two male gametes from which one male gamete reaches the
ovary where ovules are present. The male gametes enter into
embryo sac of ovule through micropyle. Now one male gamete
fuses with one female gamete (egg) present in upper part of
embryo sac to form zygote. This fusion whose product is a
zygote is called syngamy.
In seed plants fertilization is also called siphonogamy. It is also
called generative fertilization. The other male gamete fuses
with two polar nuclei one from each end of embryo sac. This
fusion forms an endosperm nucleus.
Triple Fusion
The fusion of one male gamete and two polar nuclei is called
triple fusion. It is also called vegetative fertilization. During
triple fusion endosperm nucleus is formed which acts as the
food for the developing zygote.
Zygote
The cell which is formed by the fusion of gametes (male
gamete and female gamete) is called a zygote. Zygote is
actually a fertilized egg.
Double Fertilization
In the embryo sac of the ovule two fusions, syngamy and
triple fusion takes place. This process of two fusions of
gametes taking place in embryo sac together is called double
fertilization. In other words it is the fusion of two male
gametes with two different structures in the same female
gametophyte (embryo sac) to produce two different structures
for future development of plant is called double fertilization.
After the completion of this process the remaining nuclei
present in the embryo sac disintegrate and disappear. Zygote
develops into an embryo and endosperm nucleus develops into
an endosperm, the food storage tissue of seed. Endosperm is
meant for nourishing the embryo. The embryo and endosperm
together make the seed. After fertilization ovule forms seed of
the plant and ovary forms the fruit with seeds inside it.
Seed
A seed is the reproductive unit of a plant. It contains embryo
and its food. The plant present in seed is in inactive state.
When suitable conditions are provided the new plants grow
out of the seeds.
Germination
The seed contains a future plant or embryo which develops
into an seedling under appropriate conditions. This process is
known as germination.
Sexual Reproduction In Animals
Male And Female
An animal having male sex cells called sperms in its body is
called male.
An animal having female sex cells called ova or eggs in its
body is called female.
Gametes
The cells involved in sexual reproduction are called gametes.
Ovum Or Egg
Female gamete in animals is called Ovum (plural Ova) or Egg.
Sperm
The male gamete in animal is called sperm. Sperm and ova
are extremely small cells, which can be seen only with the help
of a high power microscope.
Fertilization
The process of fusion of male gamete (sperm) with a female
gamete (egg) to form a zygote during the sexual reproduction
is called fertilization.
Embryo
The stage of development between the zygote and the newly
formed baby is called embryo.
Types Of Fertilization
1.
2.
Internal Fertilization
External Fertilization
1. Internal Fertilization
The fertilization, which occurs inside the female body, is called
internal fertilization. In mammals, birds and reptiles internal
fertilization takes place. In internal fertilization the male animal
puts his sperms into the female animal’s body. This transfer of
sperms occurs at the time of copulation (mating). These
sperms fertilize the egg inside the female animal’s body.
2. External Fertilization
The fertilization, which occurs outside the female’s body, is
called external fertilization. In amphibians and fish external
fertilization takes place. In external fertilization male and
female release their sperms and eggs in water, fertilization
takes place by collisions between sperms and eggs.
Types Of Organism
Depending upon the presence of reproducing organs the
organisms can be divided into two types:
1. Unisexual Organisms
2. Bisexual Organisms
1. Unisexual Organisms
An organism which has only one kind of reproductive organs
(male or female) in its body is called unisexual organisms. For
example, humans, frogs, birds, reptiles etc are all unisexual
organisms. In humans the males have only one reproductive
organ called testes and human female has only female
reproductive organs called ovaries in their bodies.
2. Bisexual Organisms (Hermaphrodites)
An organism, which has both male and female reproductive
organs in its body, is called a bisexual organism. The animals
like earthworms, tapeworms, leeches and starfish and most
flowering plants are bisexual organisms.
hormone called testosterone. Testes also make the male
gametes (sperms) from puberty onwards throughout the
whole life.
Advantage Of Sexual Reproduction
1.
2.
3.
4.
5.
Sexual reproduction leads to greater variety or population.
All the offsprings have genetic variation.
Sexual reproduction promotes diversity of characters in
the offsprings.
Sexual reproduction plays an important role in the origin
of new species having different characteristics.
Sexual reproduction leads to the continuous evolution of
various species to form better and still better organisms.
Human Reproductive System
Human males and females have different reproductive
systems. The reproductive systems in human beings become
functional at a definite age called puberty.
Puberty
The age at which the sex hormones or gametes begin to
produce and the boy/girl becomes sexually mature i.e.,
become able to reproduce is called puberty. Males attain
puberty at the age of 13 to 14 years. Females reach puberty at
an age of 10 to 12 years. In addition to producing gametes
male and female gonads (testes and ovaries) also produce and
secrete sex hormones with the start of puberty.
Testes produce male sex hormones called testosterone and
ovaries produce two female sex hormones called estrogen and
progesterone.
2. Scrotum
It is a small muscular pouch outside the abdominal cavity in
which the testes lie. Being outside the abdominal cavity the
temperature of scrotum is 1 to 3 degrees lower than the inside
body temperature. In this way the testes provide an optimal
temperature for the formation of sperms.
3. Epididymis
It is a coiled tube in which the sperms get stored temporarily
after their formation.
4. Vas Deferens (Sperm Duct)
Changes Taking Place After Puberty
Some changes are common to both boys and girls which are
as follows: (i) Thick hairs growing between armpits and the genital area
between thighs.
(ii) Hairs appear on legs and arms as well as on the face.
(iii) The skin becomes oily and pimples start appearing.
It is a long tube through which sperms are carried into an
organ called seminal vesicle.
Functions Of Sex Hormones
1. The sex hormones control the process of gametogenesis
i.e., production of gametes.
2. The sex hormones maintain the structure and functions of
accessory sex organs.
3. The sex hormones develop the secondary sex
characteristics.
It is an organ, which opens outside body. Sperms are carried
by urethra to penis in liquid called semen.
Male Reproductive System
The human male reproductive system consists of the following
organs:
1. Testes (Primary Reproductive organ in male)
2. Scrotum
3. Epididymis
4. Vas Deferens
5. Seminal Vesicles
6. Prostate Gland
7. Penis
1. Testes
Testes are the oval shaped organs, which lie outside the
abdominal cavity of a man. A man has two testes (singular
testis). The function of testes is to make the male sex
5. Seminal Vesicles And Prostate Gland
Seminal vesicle provides a fluid medium to the sperms called
semen and prostate gland provides nourishment to sperms.
6. Penis
Note
In males there is only one opening for the urine and sperms to
pass out from body.
Female Reproductive System
The human female reproductive system consists of the
following organs
1. Ovaries (Primary Reproductive Organ)
2. Fallopian Tubes (Oviduct)
3. Uterus
4. Cervix
5. Vagina
1. Ovaries
Ovaries are the oval shaped organs, which lie inside the
abdominal cavity of woman near the kidneys. A woman has
two ovaries. The function of the ovaries is to make female
gametes called eggs or ova and also to make two female sex
hormones estrogen and progesterone. Each ovary consists of
several thousand ovarian follicles (immature eggs). At puberty
these follicles mature to form the ripe eggs which are required
for fertilization
2. Fallopian Tubes
4.
fertilization. Thus fertilization of the ovum takes place in
the fallopian tube.
Then ovum divides rapidly by mitosis as it moves down
slowly in the fallopian tube and forms a hollow ball of
hundreds of cells.
Implantation
The hollow ball of cells now called an embryo sinks into the
soft and thick lining of the uterus and gets embedded in it.
The embedding of embryo in the thick lining of the uterus is
called implantation.
After implantation, a special tissue develops between the
uterus walls and the embryo called placenta. It is through
placenta that all the requirements of a developing embryo
(foetus) like nutrition, respiration and excretion etc. are met
from the mother’s body. The umbilical cord joins the embryo
to the placenta.
These are tubes, which lie just above the ovaries. The fallopian
tubes are not directly connected to ovaries but have a funnel
shaped opening covering the ovary. The ovum released by an
ovary goes into the fallopian tube through funnel shaped
opening. The fertilization of egg by a sperm takes place in
fallopian tubes.
3. Uterus (Womb)
It is a bag like organ, which is connected by two fallopian
tubes. The growth and development of a fertilized ovum into a
baby takes place in uterus.
4. Cervix
It is a narrow opening to which uterus is connected. It is
connected to another tubular structure called vagina, which
opens outside the body. It is meant to hold the developing
zygote in the uterus.
5. Vagina
Gestation
The time period from the fertilization upto the birth of baby is
called gestation. The average gestation period in humans is
about 280 days or 3 months 10 days or 40 weeks.
Note
In woman, the urinary opening and the vaginal openings are
separate.
Parturition
During the gestation period the foetus grows to become a
baby. Birth begins when strong muscles in the walls of the
uterus start to contract. The contraction of uterus muscles
gradually pushes the baby out of the mother’s body through
vagina or birth canal. This process is called parturition
commonly called labour. The average weight of newborn baby
is about 3.5 kg.
Complete Process Of Reproduction In Humans
Sexual Cycle In Females: Menstruation
Vagina receives the penis for putting sperms into woman’s
body. It is also called birth canal because it is through this
passage the baby is born after the completion of development
inside the uterus of mother.
Reproduction in humans takes place in the in the following
steps.
Ovulation
Release of an ovum or egg from an ovary is called ovulation.
The ovulation takes place in the mid of the sexual cycle.
Fertilization
In human beings internal fertilization takes place. The process
occurs as follows:
1.
2.
3.
The sperms made in testes of male are introduced in the
vagina of female through penis during copulation. In this
way millions of sperms are released into vagina at one
time. The sperms are highly active and moving.
The sperms then move up through cervix into the uterus.
From uterus the sperms pass into the fallopian tube. One
of the fallopian tubes contains an ovum released by an
ovary during ovulation. Only one sperm fuses with the
ovum in the fallopian tube to form a zygote. This is called
The sexual cycle in females is called menstruation cycle or
menstruation. It occurs as follows: 1. When a girl reaches puberty at the age of about 12 years,
the sex hormones released into her blood cause some of
the ova in her ovaries to become mature.
2. Usually one mature ovum is released from the ovary into
the fallopian tube once every 28 days.
3. Before ovulation the inner lining of the uterus becomes
thick and spongy and full of tiny blood vessels and
prepares itself to receive the fertilized egg.
4. If the ovum does not get fertilized due to the nonavailability of sperms in the female body then the thick
and soft inner lining of uterus is no longer needed and
hence it breaks. So, the thick and soft inner lining of
uterus along with the blood vessels and dead ovum comes
out of vagina in the form of bleeding called menstruation.
5. Menstruation usually occurs 14 days after ovulation and
usually lasts for about 2 to 5 days.
6. This cycle of menstruation is repeated again and again in
a female after 28 days and is controlled by hormones till
menopause.
Menarche
The beginning of menstruation at puberty is called menarche.
Menopause
The age at which the menstruation stops and a female loses
her ability to bear children is called menopause.
Note
Menstruation also stops temporarily when a female gets
pregnant.
Population Control
Contraception
For the prevention of pregnancy in women as population is
increasing rapidly it is necessary to take birth control
measures, family planning measures or population control
measures. All birth control measures can be broadly divided
into three categories: 1. Barrier Method
2. Chemical Method
3. Surgical Method
1. Barrier Method
In the barrier methods of preventing pregnancy, the physical
devices such as condoms and diaphragms (cervical caps) are
used. Condoms are used by males and females use
diaphragms. These devices prevent the sperms from meeting
the ovum by acting as a barrier between them.
2. Chemical Method
In the chemical methods of preventing pregnancy the females
use two types of pills.
1. Oral Pills
2. Vaginal Pills
(i) Oral Pills
It contains hormones, which stop the ovaries from
releasing eggs into the fallopian tubes. These are also
called oral contraceptives (OC)
(ii) Vaginal Pills
It contains chemicals called spermicidal which kill sperms.
3. Surgical Methods
Surgical methods of birth control are available for both male
and female.
(i) Surgical Method For Males
In males a small portion of sperm duct is removed by surgical
operation and both the cut ends are tied (legated) properly.
This prevents the sperms from coming out. This is called
vasectomy. Another method is called castration in which
testes are removed by surgical methods.
(ii) Surgical Method For Female
In females a small portion of the fallopian tubes is removed by
surgical operation and the cut ends are tied (legated). This
prevents the ovum from entering into the fallopian tube. This
is called tubectomy. Another method is called ovariectomy
in which ovaries of female are removed by surgical methods.
Intra Uterine Contraceptive Device (IUCD)
An intra uterine device copper – T is placed inside the uterus
prevents the implantation of fertilized egg in the uterus.
Sexually Transmitted Diseases
There are mainly four sexually transmitted diseases, which
are: 1.
2.
3.
4.
Syphilis
Gonorrohoea
Trichomoniases
AIDS
1. Syphilis
Bacterial Disease – Bacterium Treponema Allidium
Symptoms
1. Lesions in mucus membrane of urinogenital tract and oral
cavity.
2. Incubation period – about 34 weeks. It can be controlled
by antibiotics.
2. Gonorrohoea
Bacterial Disease – Bacterium Neisseria Gonorrhoea
Symptoms
1. Inflammation of mucus membrane of urinogenital tract
2. Burning sensation during urination
3. Can lead to female sterility or arthritis.
3. Trichiomoniases
Protozoan Disease
Symptoms
1. Burning sensation during urination.
2. Passing of urethral discharge containing pus
3. Sores in the genitals.
All the above diseases are curable by antibiotics.
4. AIDS (Viral Disease - Virus HIV)
Symptoms
1. Damages Immune System of Body.
2. A person becomes weak.
3. Body is not protected against diseases.
It is an incurable disease.