VERY SHORT ANSWER TYPE QUESTIONS (1mark each)
1. Define reproduction.
Ans : It is the process of producing new organism of the same species by existing organisms of a species.
2. Define fertilization. Where the fertilization does takes place in human female?
Ans: in oviduct.
Ans: It is defined as the fusion of a male gamete( sperm) with a female gamete(ova) to form a zygote
during sexual reproduction.
The fertilization takes place in oviduct in human female
3. Name two type of reproduction. Ans-Two main type of reproductions is asexual reproduction and sexual
reproduction.
4. The anther contains: a...Sepal b. ovules c. carpel d.. Pollen grains
Ans –Pollen grains
5. What method will you use for growing jasmine and rose plant?
Ans: Artificial mode of vegetative reproduction-layering and grafting are use for growing jasmine and rose
plant.
6. Define menstruation.
Ans-The breakdown and removal of inner thick and soft lining of uterus along with blood vessels in the form
of veginal bleeding is called menstrual flow or menstruation.
7. Write the name of male and female reproductive part of a flower.
Ans: Male reproductive part is stamen, which consists of filament and anther. Female reproductive part is
carpel, which consists of ovary, style and stigma.
8. Define gestation period. What is the gestation period in human?
Ans—The time period from the development of foetus inside the uterus till birth is called gestation period. In
humans, the gestation period lasts for 9 months or 40 week or 280 days.
9. Why do testes in mammals descend in scrotum?
Ans-The location of the scrotum regulates the temperature of the testes because sperm formation requires
a lower temperature than the body temperature.
10. Name the type of fission carried out by Amoeba.
Ans-Amoeba reproduces by binary fission in which one cell divides into two daughter cells.
11. Name two sexually transmitted diseases.
Ans- Gonorrhea and syphilis.
12. What is vegetative propagation?
Ans-- The development of new plants from parts such as roots, stem and leaves, of the plant is called
vegetative propagation.
13. Name the male and female gonads and what are the products they produce.
Ans: Male gonads - Testes, Products-Hormone testosterone which stimulates the secretion of sperm from
testes.
Female gonads – ovaries, Products-hormones estrogen and progesterone, which stimulates the secretion
of eggs.
14. Which part of human female reproduction system is called ―birth canal‖ and the ―womb?
Ans –Vagina is called the birth canal and the uterus is called the womb
15. Write the full form of IUCD and AIDS,
Ans- (a) Intra Uterine Contraceptive Device (b) Acquired immune deficiency syndrome.
17. What is syngamy?
Ans: The fusion of one male gamete with an egg to form zygote is called syngamy.
18. What is advantage of fruit formation in plant?
Ans: Fruit formation helps in easy dispersal of seed.
19. What is ovulation?
Ans: The release of ovum or the egg from the ovary is called ovulation.
20. What is menopause?
Ans-The permanent stoppage of menstruation at age of 45-50 years is called menopause.
SHORT ANSWER TYPE QUESTIONS (Each of 2 marks)
1. What is the importation of DNA copying in reproduction?
Ans-DNA copying helps to pass on the parental body features to offspring’s. It produces
variations, which are useful for the survival of species over time.
2. Why is variation beneficial to the species but not necessarily for the individual?
Ans-Organisms are normally adopted to live in a particular kind of niche. In case of
alternation in the ecological conditions of that niche, the organisms would not be able to
survive. Only the variants’ the organisms resistant to changes would survive and grow
further. Thus variation is beneficial to the species not necessarily for the individual.
3.How does binary fission differ from multiple fission?
Ans-Binary fissions results in the formation of two equally sized daughter cells, whereas
multiple fission results in the formation of many daughter cells.
4. How will an organism be benefited if it reproduces through spores?
Ans-An organism if it reproduces through spores in the following ways:
a. Spores are formed in large number.
B.Spores have an outer thick wall that protect them in adverse conditions until they come in
contact with another moist surface and begin to grow.
5. Can you think of reasons why more complex organisms cannot give rise to new
individuals through regeneration?
Ans-More complex organisms cannot give rise to new individuals through regeneration
because:
i. There body is highly complicated.
ii. There are specific organ for specific functions.
iii. There is a labour division in the body of complex organisms.
iv. Regeneration is carried out by specialized cells which are not present in complex
organisms.
6. .Why vegetative reproduction is practiced for growing some type of plants?
Ans-Vegetative reproduction is practiced in some types of plants due the following reasons:
1. The plants which do not produce viable seeds are propagated by vegetative
propagation such as banana, orange and rose.
2. Plants raised by vegetative propagation bear flower and fruit earlier than
those produce from seeds.
3. Seedless fruits are produced by vegetative propagation.
7. Why is DNA copying an essential part of the process of reproduction?
Ans-a) DNA copying provides cellular apparatus in the daughter cells.
b)DNA copying is essential for obtaining exact body design.
c) It is essential for inheritance of features from parents to offspring.
8. . What are the changes seen in girl’s at the time of puberty?
Ans-Various changes take place in girl’s body at the time of puberty :
a)Thick hair growth in the arm pit and genital area.
b) Oily skin and appearance of pimples
c) breast size begins to increase
d) Girls begins to menstruates etc.
9. . What is the role of the seminal vesicles and the prostate gland?
Ans—The secretion of seminal vesicles activates and nourishes the sperms whereas the
secretion of prostate gland contributes the mortality and fertility of sperms.
10. How is the process of pollination different from fertilization?
Ans-Pollination is the process of transfer of pollen grains from anther to stigma whereas
fertilization is the process of fusion of male gamete with a female gamete to form zygote.
11.How does the embryo get nourishment inside the mother’s body?
Ans-The embryo gets nourishment inside the mother’s body through placenta.This tissue
contains villi on the embryo’s side and is surrounded by blood from the mother’s side.
Substances like glucose and oxygen pass from the mother’s blood to the embryo through
villi.
12.If a women is using copper –Twill it help in protecting her from sexually transmitted
diseases?
Ans-No, because copper-T helps in preventing pregnancy ,but not provide protection against
sexually transmitted diseases.
13.Show by a series of labeled diagram, the manner in which reproduction in Hydra.
Ans-Hydra reproduces by budding using the regenerative cells. A bud develops as a
outgrowth in hydra due to repeated cell division of specific site, when full mature, the bud
detaches from the parent’s body and develop into new individuals.
14.Describe regeneration. Fig-
Ans-It is ability of a fully differentiate organisms to give rise to new individual from its body
parts. For example-Hydra and Planaria. If Hydra is cut into two or more pieces grow into new
and complete Hydra .This is known as regeneration.
15.Define the terms unisexual and bisexual flowers by giving one example of each.
Ans-Unisexual flower means flower which contain only one sex organs either stamen or
carpel but not both.ex-papaya, watermelon. Bisexual flower means flowe which contain both
stamen and carpels. Ex- hibiscus.
16.Leaves of the bryophyllum fallen on the ground produce new plants whereas the leaves
of rose donot. Why?
Ans-Leaf of bryophyllum show vegetative propagation in plants where a part of the body
becomes detached and develop into a new supporting plant..Here leaves of bryophyllum
having plantlets along the margine of the leaf, while this structure is absent in rose plant.
Q.17. Why does menstruation occur?
Ans. The removal of the inner, thick and soft lining of the uterus along with its blood vessels
as well as blood in the form of vaginal bleeding is called menstruation. In humans after a girl
attains puberty ovaries start producing mature ovum every month and also uterus lining gets
thickened to receive zygote. When the uterus does not receive any zygote then
menstruation occurs to excrete lining of uterus and degenerating ovum.
Q. 18. What are the different methods of contraception?
Ans. The different methods of controlling the child birth are –
(1) Hormonal methods: Various kinds of pills containing hormones which prevent the release
of egg from the ovary, without interfering with other phases of menstrual cycle, are taken
orally.
(2) Barrier method: These are the physical and chemical barriers which prevent the sperms
meeting the egg. Physical devices such as condoms, diaphragms and cervical caps are
used.
(3) Intrauterine Devices: Commonly called as I.U.Ds, they are the devices made of plastics
and come in different shapes. The most commonly among these is copper- ‘T’. These
devices are placed inside the uterine cavity and permanently kept there. It prevents the
implantation in the uterus.
(4) Surgical methods. The surgical methods are safe and permanent.
(i) Vasectomy. In this operation, a small piece of vas deferens is cut and removed and the
two ends of the cut vas deferens are tied.
(ii) Tubectomy. In this operation, fallopian tubes are cut, tied with nylon thread to close the
passage, which prevents the passage of eggs.
Q.19. How are the modes of reproduction different in unicellular and multicellular organisms?
Ans. Unicellular organisms contain only one cell so they reproduce by asexual reproduction.
Example: budding, binary and multiple-fission are some of the asexual methods. Multicellular
organisms which have complex body designs (have organ systems) ex. Humans, animals,
plants reproduce sexually.
Q.20. How does reproduction help in providing stability to populations of species?
Ans. Reproduction is the process through which an organism produces new organism of its
own kind.
It is necessary because in a population organisms die due to old age or disease thus it
keeps the number of organisms in a population constant and provides stability to a
population.
SHORT ANSWER TYPE QUESTIONS(3 Marks each)
1.What is advantages of sexual reproduction over asexual reproduction?
Ans-a) Sexual reproduction plays a prominent role in evolution of new species whereas
asexual reproduction does not.
b)Sexual reproduction provides opportunity for new combination of gens and thus causes
genetic variation. This is not applicable by asexual reproduction.
2.What are function performed by testis in human beings.?
Ans-The testis produces sperms and secrets the hormone testosterone ,which regulates the
formation of sperms and brings about changes in appearance seen in boys at the time of
puberty.
3.Why does menstruation occur?
Ans- Every month as one of the ovaries releases ovum,the uterine wall thickens and
prepares itself for receiving the developing zygote.If the fertilization of the ovum does not
take place, the lining of uterine wall slowly breaks and menstruation occurs.
4. Differentiate between natural and artificial vegetative propagation.
Ans
Natural propagation Artificial propagation
1. New parts are obtained by 1.New plants obtained from vegetative propagation
Parts of the old plants. Like cutting, layering and grafting artificially.
2.Better quality of plant cannot 2.Better quality of the plant can be maintained.
be develop.
5.Draw a diagram of a flower to show its male and female reproductive parts. Label on it : a.-
the ovary b- the anther c- the filament d- the stigma .
Ans- fig—
6.Desribe the fertilization in flower .
Ans—Pollination is followed by fertilization in plants after pollen lands on the sutable stigma,
it has to reach the female germ cells in the ovary. The pollen tube grows out of the pollen
grain through the style to reach the ovary . After fertilization zygote divide several times to
form an embryo within the ovule .The ovules than develop a tough coat and gets converted
into seed. The seed contain a future embryo which converted into a seedlings.
7. What is meant by pollination? How it takes place?
Ans—It is transfer of pollen grains from the anther of the stamen to stigma of a carpel .The
pollen grains are transferred by many agents like insects, birds mans wind etc.
8.What is ‘vegetative propagation’? Write two examples where it is used. State two reasons
of practicing vegetative propagation for giving same types of plants.
Ans-Vegetative reproduction means production of new plants from the parts of the old plant
like stem roots and leaves without the help of reproductive organs.
Reason of practicing vegetative propagation-a .It is cheaper, easier more rapid method of
propagation. b . The traits of a parents plants are preserved by vegetative priopragation.
9. Illustrate the following with the help of suitable diagram:
a) Regeneration in Planaria.
b) Budding in Hydra.
Ans-Fig
Regeneration is ability of a fully differentiated organism to give rise to new individual from its
lost body parts. For ex-in Planaria ,it can be cut into number of pieces and each pieces
grows into complete organism. In Budding a small part of the body of the parent grows out
as a ‘bud’ which than detaches and become a new organism. For ex- In Hydra bud develop
as an outgrowth due to repeated cell division, when fully mature it detach from parent body
and develop into new individual.
10. .Give differences between asexual and sexual reproduction.
Ans-
Asexual Reproduction Sexual Reproduction
1.Only one parent is involved in asexual
reproduction.
1.Two organisms, one male and one female
are involved.
2. Gametes are not formed. 2. Gametes are formed .
3. Offspring’s formed are genetically identical
to the parent.
Offspring’s formed are genetically different
from their parents.
11. Give a short account of menstruation in females.
Ans—The breakdown and removal of the inner thick and soft lining of the uterus along with
its blood vessels in the form of vaginal bleeding is called menstruation. The series of cyclic
changes involves the formation of follicles, preparation of uterine wall for implantation
,ovulation ,secretion of nutritive fluid by mature endometrium. In absence of fertilization , the
uterine wall collapse and leads to discharge of blood and mucus with unfertilized egg.
12. Describe why :
a) Scrotum remains outside the body of human males ?
b) Some plants are propagated only by vegetative propagation ?
Ans—a) Scrotum are located outside the body of human male because sperm formation
requires lower temperature than the normal body temperature .
b) Some plants are propagated only by vegetative propagation because they have lost the
capacity to produce seeds .ex-Banana, orange, Jasmine etc.
13. How does reproduction help in providing stability to populations of species ?
Ans-Niche is a place or position suitable for an organism .The DNA copying during
reproduction helps in the maintenance of the body design features that allow the organism to
use the particular niche.This is how reproduction helps in providing stability to population of
species.
LONG ANSWER TYPE QUESTIONS (5 Marks Each )
14.Draw a diagram of human female reproduction system.
.Draw a labeled diagram of longitudinal section of pistil of flower showing germination of
pollen grains on the stigma.
Ans-Fig
16. .Describe a neat and well labeled diagram of male reproductive system in human.
Ans
17. Describe the changes taking place in female reproductive organs every month
Or What will happen if ovum is not fertilized? Describe the events in a sequence wise
manner.
Or Why does menstruation occur?Ans-Cyclic changes taking place in the reproductive
organs of non pregnant women are termed as menstrual cycle. They take place if the ovum
is not fertilized .I mportant events in sexual cycle of females:
Ovulation-Release of mature ovum from the ovary.
Menstruation-Degeneration and removal of inner thickened lining of uterus along with blood
after every 28 days, through the vaginal canal Both these events stop if pregnancy occurs
and are resumed after the child birth: If fertilization does not occur, both the processes keep
occurring periodically every month.
18.How do following organisms reproduce?
a)Amoeba
Ans-binary fission
b) Planaria
Ans-fragmantation, regeneration, transverse binary fission
c) Yeast
Ans-budding ,spore formation
d) Frog
Ans-Sexual
e)Rose
Ans-grafting, cutting
f) Bacteria
Ans-binary fission, spore formation
1. Define reproduction.
Ans : It is the process of producing new organism of the same species by existing organisms of a species.
2. Define fertilization. Where the fertilization does takes place in human female?
Ans: in oviduct.
Ans: It is defined as the fusion of a male gamete( sperm) with a female gamete(ova) to form a zygote
during sexual reproduction.
The fertilization takes place in oviduct in human female
3. Name two type of reproduction. Ans-Two main type of reproductions is asexual reproduction and sexual
reproduction.
4. The anther contains: a...Sepal b. ovules c. carpel d.. Pollen grains
Ans –Pollen grains
5. What method will you use for growing jasmine and rose plant?
Ans: Artificial mode of vegetative reproduction-layering and grafting are use for growing jasmine and rose
plant.
6. Define menstruation.
Ans-The breakdown and removal of inner thick and soft lining of uterus along with blood vessels in the form
of veginal bleeding is called menstrual flow or menstruation.
7. Write the name of male and female reproductive part of a flower.
Ans: Male reproductive part is stamen, which consists of filament and anther. Female reproductive part is
carpel, which consists of ovary, style and stigma.
8. Define gestation period. What is the gestation period in human?
Ans—The time period from the development of foetus inside the uterus till birth is called gestation period. In
humans, the gestation period lasts for 9 months or 40 week or 280 days.
9. Why do testes in mammals descend in scrotum?
Ans-The location of the scrotum regulates the temperature of the testes because sperm formation requires
a lower temperature than the body temperature.
10. Name the type of fission carried out by Amoeba.
Ans-Amoeba reproduces by binary fission in which one cell divides into two daughter cells.
11. Name two sexually transmitted diseases.
Ans- Gonorrhea and syphilis.
12. What is vegetative propagation?
Ans-- The development of new plants from parts such as roots, stem and leaves, of the plant is called
vegetative propagation.
13. Name the male and female gonads and what are the products they produce.
Ans: Male gonads - Testes, Products-Hormone testosterone which stimulates the secretion of sperm from
testes.
Female gonads – ovaries, Products-hormones estrogen and progesterone, which stimulates the secretion
of eggs.
14. Which part of human female reproduction system is called ―birth canal‖ and the ―womb?
Ans –Vagina is called the birth canal and the uterus is called the womb
15. Write the full form of IUCD and AIDS,
Ans- (a) Intra Uterine Contraceptive Device (b) Acquired immune deficiency syndrome.
17. What is syngamy?
Ans: The fusion of one male gamete with an egg to form zygote is called syngamy.
18. What is advantage of fruit formation in plant?
Ans: Fruit formation helps in easy dispersal of seed.
19. What is ovulation?
Ans: The release of ovum or the egg from the ovary is called ovulation.
20. What is menopause?
Ans-The permanent stoppage of menstruation at age of 45-50 years is called menopause.
SHORT ANSWER TYPE QUESTIONS (Each of 2 marks)
1. What is the importation of DNA copying in reproduction?
Ans-DNA copying helps to pass on the parental body features to offspring’s. It produces
variations, which are useful for the survival of species over time.
2. Why is variation beneficial to the species but not necessarily for the individual?
Ans-Organisms are normally adopted to live in a particular kind of niche. In case of
alternation in the ecological conditions of that niche, the organisms would not be able to
survive. Only the variants’ the organisms resistant to changes would survive and grow
further. Thus variation is beneficial to the species not necessarily for the individual.
3.How does binary fission differ from multiple fission?
Ans-Binary fissions results in the formation of two equally sized daughter cells, whereas
multiple fission results in the formation of many daughter cells.
4. How will an organism be benefited if it reproduces through spores?
Ans-An organism if it reproduces through spores in the following ways:
a. Spores are formed in large number.
B.Spores have an outer thick wall that protect them in adverse conditions until they come in
contact with another moist surface and begin to grow.
5. Can you think of reasons why more complex organisms cannot give rise to new
individuals through regeneration?
Ans-More complex organisms cannot give rise to new individuals through regeneration
because:
i. There body is highly complicated.
ii. There are specific organ for specific functions.
iii. There is a labour division in the body of complex organisms.
iv. Regeneration is carried out by specialized cells which are not present in complex
organisms.
6. .Why vegetative reproduction is practiced for growing some type of plants?
Ans-Vegetative reproduction is practiced in some types of plants due the following reasons:
1. The plants which do not produce viable seeds are propagated by vegetative
propagation such as banana, orange and rose.
2. Plants raised by vegetative propagation bear flower and fruit earlier than
those produce from seeds.
3. Seedless fruits are produced by vegetative propagation.
7. Why is DNA copying an essential part of the process of reproduction?
Ans-a) DNA copying provides cellular apparatus in the daughter cells.
b)DNA copying is essential for obtaining exact body design.
c) It is essential for inheritance of features from parents to offspring.
8. . What are the changes seen in girl’s at the time of puberty?
Ans-Various changes take place in girl’s body at the time of puberty :
a)Thick hair growth in the arm pit and genital area.
b) Oily skin and appearance of pimples
c) breast size begins to increase
d) Girls begins to menstruates etc.
9. . What is the role of the seminal vesicles and the prostate gland?
Ans—The secretion of seminal vesicles activates and nourishes the sperms whereas the
secretion of prostate gland contributes the mortality and fertility of sperms.
10. How is the process of pollination different from fertilization?
Ans-Pollination is the process of transfer of pollen grains from anther to stigma whereas
fertilization is the process of fusion of male gamete with a female gamete to form zygote.
11.How does the embryo get nourishment inside the mother’s body?
Ans-The embryo gets nourishment inside the mother’s body through placenta.This tissue
contains villi on the embryo’s side and is surrounded by blood from the mother’s side.
Substances like glucose and oxygen pass from the mother’s blood to the embryo through
villi.
12.If a women is using copper –Twill it help in protecting her from sexually transmitted
diseases?
Ans-No, because copper-T helps in preventing pregnancy ,but not provide protection against
sexually transmitted diseases.
13.Show by a series of labeled diagram, the manner in which reproduction in Hydra.
Ans-Hydra reproduces by budding using the regenerative cells. A bud develops as a
outgrowth in hydra due to repeated cell division of specific site, when full mature, the bud
detaches from the parent’s body and develop into new individuals.
14.Describe regeneration. Fig-
Ans-It is ability of a fully differentiate organisms to give rise to new individual from its body
parts. For example-Hydra and Planaria. If Hydra is cut into two or more pieces grow into new
and complete Hydra .This is known as regeneration.
15.Define the terms unisexual and bisexual flowers by giving one example of each.
Ans-Unisexual flower means flower which contain only one sex organs either stamen or
carpel but not both.ex-papaya, watermelon. Bisexual flower means flowe which contain both
stamen and carpels. Ex- hibiscus.
16.Leaves of the bryophyllum fallen on the ground produce new plants whereas the leaves
of rose donot. Why?
Ans-Leaf of bryophyllum show vegetative propagation in plants where a part of the body
becomes detached and develop into a new supporting plant..Here leaves of bryophyllum
having plantlets along the margine of the leaf, while this structure is absent in rose plant.
Q.17. Why does menstruation occur?
Ans. The removal of the inner, thick and soft lining of the uterus along with its blood vessels
as well as blood in the form of vaginal bleeding is called menstruation. In humans after a girl
attains puberty ovaries start producing mature ovum every month and also uterus lining gets
thickened to receive zygote. When the uterus does not receive any zygote then
menstruation occurs to excrete lining of uterus and degenerating ovum.
Q. 18. What are the different methods of contraception?
Ans. The different methods of controlling the child birth are –
(1) Hormonal methods: Various kinds of pills containing hormones which prevent the release
of egg from the ovary, without interfering with other phases of menstrual cycle, are taken
orally.
(2) Barrier method: These are the physical and chemical barriers which prevent the sperms
meeting the egg. Physical devices such as condoms, diaphragms and cervical caps are
used.
(3) Intrauterine Devices: Commonly called as I.U.Ds, they are the devices made of plastics
and come in different shapes. The most commonly among these is copper- ‘T’. These
devices are placed inside the uterine cavity and permanently kept there. It prevents the
implantation in the uterus.
(4) Surgical methods. The surgical methods are safe and permanent.
(i) Vasectomy. In this operation, a small piece of vas deferens is cut and removed and the
two ends of the cut vas deferens are tied.
(ii) Tubectomy. In this operation, fallopian tubes are cut, tied with nylon thread to close the
passage, which prevents the passage of eggs.
Q.19. How are the modes of reproduction different in unicellular and multicellular organisms?
Ans. Unicellular organisms contain only one cell so they reproduce by asexual reproduction.
Example: budding, binary and multiple-fission are some of the asexual methods. Multicellular
organisms which have complex body designs (have organ systems) ex. Humans, animals,
plants reproduce sexually.
Q.20. How does reproduction help in providing stability to populations of species?
Ans. Reproduction is the process through which an organism produces new organism of its
own kind.
It is necessary because in a population organisms die due to old age or disease thus it
keeps the number of organisms in a population constant and provides stability to a
population.
SHORT ANSWER TYPE QUESTIONS(3 Marks each)
1.What is advantages of sexual reproduction over asexual reproduction?
Ans-a) Sexual reproduction plays a prominent role in evolution of new species whereas
asexual reproduction does not.
b)Sexual reproduction provides opportunity for new combination of gens and thus causes
genetic variation. This is not applicable by asexual reproduction.
2.What are function performed by testis in human beings.?
Ans-The testis produces sperms and secrets the hormone testosterone ,which regulates the
formation of sperms and brings about changes in appearance seen in boys at the time of
puberty.
3.Why does menstruation occur?
Ans- Every month as one of the ovaries releases ovum,the uterine wall thickens and
prepares itself for receiving the developing zygote.If the fertilization of the ovum does not
take place, the lining of uterine wall slowly breaks and menstruation occurs.
4. Differentiate between natural and artificial vegetative propagation.
Ans
Natural propagation Artificial propagation
1. New parts are obtained by 1.New plants obtained from vegetative propagation
Parts of the old plants. Like cutting, layering and grafting artificially.
2.Better quality of plant cannot 2.Better quality of the plant can be maintained.
be develop.
5.Draw a diagram of a flower to show its male and female reproductive parts. Label on it : a.-
the ovary b- the anther c- the filament d- the stigma .
Ans- fig—
6.Desribe the fertilization in flower .
Ans—Pollination is followed by fertilization in plants after pollen lands on the sutable stigma,
it has to reach the female germ cells in the ovary. The pollen tube grows out of the pollen
grain through the style to reach the ovary . After fertilization zygote divide several times to
form an embryo within the ovule .The ovules than develop a tough coat and gets converted
into seed. The seed contain a future embryo which converted into a seedlings.
7. What is meant by pollination? How it takes place?
Ans—It is transfer of pollen grains from the anther of the stamen to stigma of a carpel .The
pollen grains are transferred by many agents like insects, birds mans wind etc.
8.What is ‘vegetative propagation’? Write two examples where it is used. State two reasons
of practicing vegetative propagation for giving same types of plants.
Ans-Vegetative reproduction means production of new plants from the parts of the old plant
like stem roots and leaves without the help of reproductive organs.
Reason of practicing vegetative propagation-a .It is cheaper, easier more rapid method of
propagation. b . The traits of a parents plants are preserved by vegetative priopragation.
9. Illustrate the following with the help of suitable diagram:
a) Regeneration in Planaria.
b) Budding in Hydra.
Ans-Fig
Regeneration is ability of a fully differentiated organism to give rise to new individual from its
lost body parts. For ex-in Planaria ,it can be cut into number of pieces and each pieces
grows into complete organism. In Budding a small part of the body of the parent grows out
as a ‘bud’ which than detaches and become a new organism. For ex- In Hydra bud develop
as an outgrowth due to repeated cell division, when fully mature it detach from parent body
and develop into new individual.
10. .Give differences between asexual and sexual reproduction.
Ans-
Asexual Reproduction Sexual Reproduction
1.Only one parent is involved in asexual
reproduction.
1.Two organisms, one male and one female
are involved.
2. Gametes are not formed. 2. Gametes are formed .
3. Offspring’s formed are genetically identical
to the parent.
Offspring’s formed are genetically different
from their parents.
11. Give a short account of menstruation in females.
Ans—The breakdown and removal of the inner thick and soft lining of the uterus along with
its blood vessels in the form of vaginal bleeding is called menstruation. The series of cyclic
changes involves the formation of follicles, preparation of uterine wall for implantation
,ovulation ,secretion of nutritive fluid by mature endometrium. In absence of fertilization , the
uterine wall collapse and leads to discharge of blood and mucus with unfertilized egg.
12. Describe why :
a) Scrotum remains outside the body of human males ?
b) Some plants are propagated only by vegetative propagation ?
Ans—a) Scrotum are located outside the body of human male because sperm formation
requires lower temperature than the normal body temperature .
b) Some plants are propagated only by vegetative propagation because they have lost the
capacity to produce seeds .ex-Banana, orange, Jasmine etc.
13. How does reproduction help in providing stability to populations of species ?
Ans-Niche is a place or position suitable for an organism .The DNA copying during
reproduction helps in the maintenance of the body design features that allow the organism to
use the particular niche.This is how reproduction helps in providing stability to population of
species.
LONG ANSWER TYPE QUESTIONS (5 Marks Each )
14.Draw a diagram of human female reproduction system.
.Draw a labeled diagram of longitudinal section of pistil of flower showing germination of
pollen grains on the stigma.
Ans-Fig
16. .Describe a neat and well labeled diagram of male reproductive system in human.
Ans
17. Describe the changes taking place in female reproductive organs every month
Or What will happen if ovum is not fertilized? Describe the events in a sequence wise
manner.
Or Why does menstruation occur?Ans-Cyclic changes taking place in the reproductive
organs of non pregnant women are termed as menstrual cycle. They take place if the ovum
is not fertilized .I mportant events in sexual cycle of females:
Ovulation-Release of mature ovum from the ovary.
Menstruation-Degeneration and removal of inner thickened lining of uterus along with blood
after every 28 days, through the vaginal canal Both these events stop if pregnancy occurs
and are resumed after the child birth: If fertilization does not occur, both the processes keep
occurring periodically every month.
18.How do following organisms reproduce?
a)Amoeba
Ans-binary fission
b) Planaria
Ans-fragmantation, regeneration, transverse binary fission
c) Yeast
Ans-budding ,spore formation
d) Frog
Ans-Sexual
e)Rose
Ans-grafting, cutting
f) Bacteria
Ans-binary fission, spore formation
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