REPRODUCTION
6
CHAPTER
Binary Fission :
CONTENTS
When one mature unicellular organism like
Reproduction Amoeba splits into two daughter individuals, the
process is called binary fission.
Asexual reproduction This type of reproduction occurs when
environmental conditions are most favourable
Sexual reporoduction
Sexual reproduction in Human
1
Development of Embryo
Gestation & Child birth
Metamorphosis
2
REPRODUCTION
The process by which living organisms produce Parent Cell
offsprings of their own kind is called Division of
reproduction. Nucleus
3
Types of reproduction :
Asexual reproduction
Sexual reproduction
Daughter Cell Daughter Cell
ASEXUAL REPRODUCTION
This occurs without involving sex organs.
Asexual reproduction requires only one parent for
multiplication and formation of new offsprings. It 4 5
does not require both male and female parents. It
is the simplest form of reproduction and is
commonly found in unicellular organisms (hydra, In Amoeba, the nucleus first divides into two
nuclei. Then the cytoplasm divides into two parts,
Amoeba, Paramecium) and lower animals like
each containing a nucleus. A constriction
starfish, sponges and worms
develops in the body which gradually deepens to
The various methods of asexual reproduction form two daughter amoebae. This type of
commonly found in animals are as follows : reproduction is binary fission.
, Budding : External fertillization : When the eggs are
In this type of reproduction, as seen in hydra, a fertilized outside the body of the female, it is
small outgrowth appears on the body of the called external fertilization. Fertilization in
organism. This outgrowth is called a bud. The animals like frog and fish is external. In these
nucleus of the parent body divides into two and organisms, the eggs are discharged ouside the
one nucleus goes into the bud. The bud grows and body, i.e., in water. On these eggs, the male
finally gets detached from the parent body of discharges the sperms to fertilize them
hydra and begins to live as an independent
individual SEXUAL REPRODUCTION IN HUMAN
The Male Reproductive System :
The male reproductive system of humans consists
of the following organs
Kidney
Bud
Since new individuals develop from the bud in Bladder
Prostate gland
hydra, this type of reproduction is called budding Vas deferens
Besides these two processes, there are other Cowper's gland
Urethra
methods of asexual reproduction which you will
study in your higher classes. Testis
SEXUAL REPRODUCTION
This is one of the most common methods of Penis Scrotum
reproduction, found in most animals including
human beings. In sexual reproduction, two
parents, one male and the other female, are Testies :
required. Each parent produces reproductive cells There is a pair of testes which lie outside the body
called gametes. The male gamete is called a within the scrotum. They produce millions of
sperm. and the female gamete is known as an egg sperms
or ovum. Vas Deferens (Sperm duct) :
Those organisms which produce only one type of Vas deferens are two in numbers. This duct
gamete are called unisexual, e.g. dogs, cat, fish, connects each testies to the urethra. It carries
man, birds, reptiles sperms to the urethra along with the secretion of
reproductive glands. This mixture of sperms and
Those organisms which have both the male and secretions is called semen.
female sex organs in their body are called
bisexual or hermaphrodite, e.g. earthworm, leech, Urerthra :
hydra. The two vas deferens open into the urethra and
pass through the penis.
Fertilisation :
Penis :
The prosess of fusion of the sperm with the ovum is Urethra leads to a muscular organ called penis. It
called fertilization. Zygote is formed after is used to deliver semen into the vagina of the
fertilization. female during mating. It is used to pass urine as
Types of fertilisation : well
There are two types of fertilization in animals
Sperms :
Internal fertilization : When the fertilization The sexual maturity in human males is attained
occurs inside the body of female, as it happens in around the age of 14 to 15 years.
humans, it is called internal fertilization. Internal Sperms are produced in millions by the testes.
fertilization takes place in most of higher animals, They are very small in size. Each sperm consists
e.g. birds, mammals. of a head, a middle piece and a tail. Sperms swim
in semen with the help of a tail.
6
CHAPTER
Binary Fission :
CONTENTS
When one mature unicellular organism like
Reproduction Amoeba splits into two daughter individuals, the
process is called binary fission.
Asexual reproduction This type of reproduction occurs when
environmental conditions are most favourable
Sexual reporoduction
Sexual reproduction in Human
1
Development of Embryo
Gestation & Child birth
Metamorphosis
2
REPRODUCTION
The process by which living organisms produce Parent Cell
offsprings of their own kind is called Division of
reproduction. Nucleus
3
Types of reproduction :
Asexual reproduction
Sexual reproduction
Daughter Cell Daughter Cell
ASEXUAL REPRODUCTION
This occurs without involving sex organs.
Asexual reproduction requires only one parent for
multiplication and formation of new offsprings. It 4 5
does not require both male and female parents. It
is the simplest form of reproduction and is
commonly found in unicellular organisms (hydra, In Amoeba, the nucleus first divides into two
nuclei. Then the cytoplasm divides into two parts,
Amoeba, Paramecium) and lower animals like
each containing a nucleus. A constriction
starfish, sponges and worms
develops in the body which gradually deepens to
The various methods of asexual reproduction form two daughter amoebae. This type of
commonly found in animals are as follows : reproduction is binary fission.
, Budding : External fertillization : When the eggs are
In this type of reproduction, as seen in hydra, a fertilized outside the body of the female, it is
small outgrowth appears on the body of the called external fertilization. Fertilization in
organism. This outgrowth is called a bud. The animals like frog and fish is external. In these
nucleus of the parent body divides into two and organisms, the eggs are discharged ouside the
one nucleus goes into the bud. The bud grows and body, i.e., in water. On these eggs, the male
finally gets detached from the parent body of discharges the sperms to fertilize them
hydra and begins to live as an independent
individual SEXUAL REPRODUCTION IN HUMAN
The Male Reproductive System :
The male reproductive system of humans consists
of the following organs
Kidney
Bud
Since new individuals develop from the bud in Bladder
Prostate gland
hydra, this type of reproduction is called budding Vas deferens
Besides these two processes, there are other Cowper's gland
Urethra
methods of asexual reproduction which you will
study in your higher classes. Testis
SEXUAL REPRODUCTION
This is one of the most common methods of Penis Scrotum
reproduction, found in most animals including
human beings. In sexual reproduction, two
parents, one male and the other female, are Testies :
required. Each parent produces reproductive cells There is a pair of testes which lie outside the body
called gametes. The male gamete is called a within the scrotum. They produce millions of
sperm. and the female gamete is known as an egg sperms
or ovum. Vas Deferens (Sperm duct) :
Those organisms which produce only one type of Vas deferens are two in numbers. This duct
gamete are called unisexual, e.g. dogs, cat, fish, connects each testies to the urethra. It carries
man, birds, reptiles sperms to the urethra along with the secretion of
reproductive glands. This mixture of sperms and
Those organisms which have both the male and secretions is called semen.
female sex organs in their body are called
bisexual or hermaphrodite, e.g. earthworm, leech, Urerthra :
hydra. The two vas deferens open into the urethra and
pass through the penis.
Fertilisation :
Penis :
The prosess of fusion of the sperm with the ovum is Urethra leads to a muscular organ called penis. It
called fertilization. Zygote is formed after is used to deliver semen into the vagina of the
fertilization. female during mating. It is used to pass urine as
Types of fertilisation : well
There are two types of fertilization in animals
Sperms :
Internal fertilization : When the fertilization The sexual maturity in human males is attained
occurs inside the body of female, as it happens in around the age of 14 to 15 years.
humans, it is called internal fertilization. Internal Sperms are produced in millions by the testes.
fertilization takes place in most of higher animals, They are very small in size. Each sperm consists
e.g. birds, mammals. of a head, a middle piece and a tail. Sperms swim
in semen with the help of a tail.
