8. How do Organisms Reproducer ? SEBA/ASSEB Class 10 Science– Important Questions and Answers | Assam HSLC

SEBA/ASSEB Class 10 Science Chapter 8: How do Organisms Reproducer ? Important Questions and Answers | HSLC Assam

Chapter 8: How do Organisms Reproducer ?

Multiple Choose Question and Answer :

Question: Which among the following is not the function of testes at puberty?

(i) formation of germ cells             (ii) secretion of testosterone

(iii) development of placenta       (iv) secretion of estrogen

(a) (i) and (ii)         (b) (ii) and (iii)         (c) (iii) and (iv)        (d) (i) and (iv)

Answer: (c) (iii) and (iv)

[ The functions of the testes at puberty include the formation of germ cells (sperm), and the secretion of testosterone. ]

Question: The correct sequence of organs in the male reproductive system for transport of sperms is

(a) testis → vasdeferens → urethra      (b) testis → ureter → urethra

(c) testis → urethra → ureter                 (d) testis → vasdeferens → ureter

Answer: (a) Testis → Vas deferens → Urethra

[ Sperms are produced in the testes, travel through the vas deferens and exit through the urethra during ejaculation.]

Question: Which among the following diseases is not sexually transmitted?

(a) Syphillis        (b) Hepatitis        (c) HIV - AIDS     (d) Gonorrhoea

Answer: (b) Hepatitis

[ Hepatitis is not exclusively a sexually transmitted disease.]

Question: The process of giving rise to new individual organisms from the body parts of many fully differentiated organisms is known as : [SEBA 2023]

(a) Regeneration  (b) Budding  (c) Fragmentation   (d) Fission

Answer:  (c) Fragmentation.

[ Fragmentation is the process of giving rise to new individual organisms from the body parts of many fully differentiated organisms.]

Question: Which of the following statements are true for flowers?

(i) Flowers are always bisexual         (ii) They are the sexual reproductive organs

(iii) They are produced in all groups of plants       (iv) After fertilisation they give rise to fruits

(a) (i) and (iv)       (b) (ii) and (iii)        (c) (i) and (iii)         (d) (ii) and (iv)

Answer: (d) (ii) and (iv)

[ (ii) Flowers are the sexual reproductive organs. (iv) After fertilization, they give rise to fruits.

Flowers can be either bisexual (containing both male and female reproductive structures) or unisexual (containing either male or female reproductive structures) ]

Question:Binary fission occurs in : [SEBA 2023]

(a) Amoeba    (b) Paramoecium  (c)  Planaria    (d) All of these

Answer: (d) All of these.

[ Binary fission is a form of asexual reproduction in which a single organism divides into two equal and identical individuals.]

Question:   and  are the reproductive parts of a flower which contain the germ-cells . [SEBA 2023]

Answer:  Stamens and pistil .

[ Stamens and pistil are the reproductive parts of a flower which contain the germ-cells.]

Question: Asexual reproduction takes place through budding in [2025]

(a) yeast     (b) amoeba       (c) leishmania       (d) plasmodium

Answer: (a) yeast .      

Question: What happens when the egg is not fertilized ? [2025]

(a) Dies immediately  (b) Lives for about one day     (c) Lives for about one week    (d) All of the above

Answer: (b) Lives for about one day .

[When the egg (ovum) is not fertilized, it lives for about one day (approximately 24 hours) after ovulation]    

Question: Flowers of habisscus, mustard, etc.., contain both stamens and carpels. Therefore, they are [2025]

(a) unisexual       (b) bisexual    (c) grafting    (d)  fragmentation

Answer: (b) bisexual .    

Question: In the list of organisms given below, those that reproduce by the asexual method are

(i) banana           (ii) dog           (iii) yeast             (iv) Amoeba

(a) (ii) and (iv)         (b) (i), (iii) and (iv)            (c) (i) and (iv)           (d) (ii), (iii) and (iv)

Answer: (b) (i), (iii) and (iv)

[ The organisms that reproduce by the asexual method in the given list are: (i) Banana (through rhizomes or suckers) (iii) Yeast (through budding or fission) (iv) Amoeba (through binary fission) ]

Question: Single-celled animals like amoeba reproduce by the process of ………….. [2024]

(a) binary fission     (b) multiple fission     (c) budding     (d) fragmentation

Answer: (a) binary fission .     

Question: Vegetative propagation refers to formation of new plants from

(a) stem, roots and flowers      (b) stem, roots and leaves

(c) stem, flowers and fruits      (d) stem, leaves and flowers

Answer: (b) Stem, roots, and leaves

[ Vegetative propagation refers to the formation of new plants from structures such as stems, roots, and leaves.]

Question: In a flower, the parts that produce male and female gametes (germ cells) are

(a) stamen and anther       (b) filament and stigma

(c) anther and ovary          (d) stamen and style

Answer: (c) Anther and ovary

[ In a flower, the parts that produce male and female gametes (germ cells) are the anther and the ovary.]

Question: Which of the following is the correct sequence of events of sexual reproduction in a flower?

(a) pollination, fertilisation, seedling, embryo        (b) seedling, embryo, fertilisation, pollination

(c) pollination, fertilisation, embryo, seedling         (d) embryo, seedling, pollination, fertilization

Answer: (c) Pollination, fertilisation, embryo, seedling

Question: Offspring formed by asexual method of reproduction have greater similarity among themselves because

(i) asexual reproduction involves only one parent

(ii) asexual reproduction does not involve gametes

(iii) asexual reproduction occurs before sexual reproduction

(iv) asexual reproduction occurs after sexual reproduction

(a) (i) and (ii)          (b) (i) and (iii)           (c) (ii) and (iv)        (d) (iii) and (iv)

Answer: (a) (i) and (ii)

[ Offspring formed by asexual reproduction have greater similarity among themselves because: (i) Asexual reproduction involves only one parent. (ii) Asexual reproduction does not involve gametes, and there is no mixing of genetic material from different individuals. ]

Question: Characters transmitted from parents to offspring are present in

(a) cytoplasm       (b) ribosome        (c) golgi bodies        (d) genes

Answer: (d) Genes

[ Characters transmitted from parents to offspring are present in genes. ]

Question: The anther contains ……………….. [2024]

(a) sepals    (b) ovules     (c) carpels     (d) pollen grains

Answer: (d) pollen grains

[The anther contains pollen grains.]

Question: In Rhizopus, tubular thread-like structures bearing sporangia at their tips are called

(a) filaments        (b) hyphae          (c) rhizoids           (d) roots

Answer: (b) Hyphae

[ In Rhizopus, tubular thread-like structures bearing sporangia at their tips are called hyphae. ]

Question: A feature of reproduction that is common to Amoeba, Spirogyra and Yeast is that

(a) they reproduce asexually               (b) they are all unicellular

(c) they reproduce only sexually         (d) they are all multicellular

Answer: (a) They reproduce asexually

[ A feature of reproduction that is common to Amoeba, Spirogyra, and Yeast is that they reproduce asexually.]

Question: Which of the following is not a part of the female reproductive system of human beings ? [SEBA 2024]

(a) Ovary      (b) Uterus    (c) Vas deferens    (d) Fallopian tube

Answer: (c) Vas deferens.

Question: The correct sequence of reproductive stages seen in flowering plants is

(a) gametes, zygote, embryo, seedling       (b) zygote, gametes, embryo, seedling

(c) seedling, embryo, zygote, gametes       (d) gametes, embryo, zygote, seedling

Answer: (a) Gametes, zygote, embryo, seedling

Question: The ability of a cell to divide into several cells during reproduction in Plasmodium is called

(a) budding         (b) reduction division        (c) binary fission        (d) multiple fission

Answer: (d) Multiple fission

[ The ability of a cell to divide into several cells during reproduction in Plasmodium is called multiple fission. ]

Question: Which of the following is an example of reproduction by binary fission?

(a) Hydra       (b) Amoeba        (c) Rhizopus        (d) Planaria

Answer: (b) Amoeba.

Question: Which of the following organisms reproduces by budding?

(a) Leishmania         (b) Plasmodium           (c) Hydra           (d) Spirogyra

Answer: (c) Hydra.

Question: The transfer of pollen grains from the anther to the stigma is called:

(a) Fertilisation         (b) Pollination           (c) Germination          (d) Implantation

Answer: (b) Pollination.

Question: Which part of a flower develops into a fruit after fertilisation?

(a) Ovule            (b) Ovary           (c) Stigma          (d) Anther

Answer: (B) Ovary.

Question: Which of the following is the male reproductive part of a flower?

(a) Pistil            (b) Ovary            (c) Stamen            (d) Stigma

Answer: (c) Stamen.

Question: In human beings, fertilisation normally takes place in the:

(a) Uterus          (b) Ovary             (c) Oviduct             (d) Vagina

Answer: (c) Oviduct (fallopian tube).

Question: Which hormone is primarily responsible for the development of male secondary sexual characteristics?

(a) Oestrogen          (b) Testosterone           (c) Insulin            (d) Thyroxine

Answer: (b) Testosterone.

Question: Which contraceptive method also helps reduce the risk of sexually transmitted infections (STIs)?

(a) Oral contraceptive pills            (b) Copper-T              (c) Condom              (d) Tubectomy

Answer: (c) Condom.

Question: Vegetative propagation in Bryophyllum takes place through:

(a) Roots           (b) Stems                 (c) Leaves            (d) Flowers

Answer: (c) Leaves.

Question: The main advantage of sexual reproduction is that it:

(a) Produces genetically identical offspring      (b) Requires only one parent in all cases

(c) Creates variations among offspring               (d) Does not involve gametes

Answer: (c) Creates variations among offspring.

Question: Which structure produces sperms in human males?

(a) Prostate gland         (b) Testes         (c) Vas deferens           (d) Urethra

Answer:  (b) Testes.

Question: The implantation of the embryo takes place in the:

(a) Ovary         (b) Oviduct           (c) Uterine lining       (d) Cervix

Answer: (c) Uterine lining.

Assertion and Reasoning Questions

(A) Both Assertion and Reason are true, and Reason is the correct explanation of Assertion.

(B) Both Assertion and Reason are true, but Reason is not the correct explanation of Assertion.

(C) Assertion is true, but Reason is false.

(D) Assertion is false, but Reason is true.

Question: Assertion: Sexual reproduction produces variations among offspring.

Reason: DNA copying during reproduction is not always perfectly accurate, and sexual reproduction combines genetic material from two parents.

Answer: (A) Both statements are true, and the Reason correctly explains the Assertion.

Question: Assertion: Binary fission in Leishmania occurs in a definite plane.

Reason: Leishmania has a whip-like structure at one end and its body organisation determines the plane of division.

Answer:  (A) Both statements are true, and the Reason correctly explains the Assertion.

Question: Assertion: Pollination and fertilisation are the same process.

Reason: Pollination is the transfer of pollen grains from the anther to the stigma, whereas fertilisation involves the fusion of male and female gametes.

Answer: (D) The Assertion is false, but the Reason is true.

Question: Assertion: The uterus provides a suitable environment for the development of the embryo.

Reason: After fertilisation, the embryo gets implanted in the lining of the uterus.

Answer:  (A) Both statements are true, and the Reason correctly explains the Assertion.

Question: Assertion: Vegetative propagation produces offspring that are generally genetically similar to the parent.

Reason: Vegetative propagation involves the formation of new plants from vegetative parts without the fusion of gametes.

Answer:  (A) Both statements are true, and the Reason correctly explains the Assertion.

Question: Assertion: Condoms help prevent unwanted pregnancy and reduce the risk of sexually transmitted infections.

Reason: Condoms act as a physical barrier that reduces the chances of sperm entering the female reproductive tract and of infection transmission.

Answer:  (A) Both statements are true, and the Reason correctly explains the Assertion.

Question: Assertion: The testes are located outside the abdominal cavity in the scrotum.

Reason: Sperm formation requires a temperature slightly lower than the normal body temperature.

Answer:  (A) Both statements are true, and the Reason correctly explains the Assertion.

Question: Assertion: DNA copying during reproduction is always perfectly accurate.

Reason: Small errors during DNA copying can produce variations among offspring.

Answer: (D) The Assertion is false, but the Reason is true.

Very Short Question and Answer :

Question: What is cross-pollination ? [1M SEBA 2018]

Answer: Cross-pollination is the transfer of pollen grains from the anther of a flower of one plant to the stigma of a flower of another plant of the same species.  

Question:  Where is the zygote located in the flower after fertilization?

Answer: After fertilization, the zygote in the flower is located within the ovule , which is found inside the ovary of the pistil.

Question:  What is reproduction?

Answer: Reproduction is the biological process by which living organisms produce new individuals of their own kind.

Question:  What is the basic event in reproduction that produces variations?

Answer: Small inaccuracies during DNA copying can produce variations. Sexual reproduction also combines genetic material from two parents, increasing variation.

Question:  Name the two main types of reproduction.

Answer: Asexual reproduction and sexual reproduction.

Question:  What is binary fission?

Answer: Binary fission is a type of asexual reproduction in which one parent cell divides into two daughter cells.

Question: What is budding? Give one example.

Answer: Budding is a type of asexual reproduction in which a small outgrowth develops on the parent and grows into a new individual. Example: Hydra.

Question: What is vegetative propagation?

Answer:  Vegetative propagation is a type of asexual reproduction in which new plants develop from vegetative parts such as roots, stems or leaves.

Question: Name the male and female reproductive parts of a flower.

Answer:  The male reproductive part is the stamen, and the female reproductive part is the pistil (carpel).

Question: Define fertilisation.

Answer:  Fertilisation is the fusion of male and female gametes to form a zygote.

Question: What is menstruation?

Answer:  Menstruation is the periodic shedding of the uterine lining along with blood and tissue when fertilisation and pregnancy do not occur.

Question: Name the hormone responsible for the development of female secondary sexual characteristics.

Answer:  Oestrogen.

Question: What is implantation?

Answer:  Implantation is the attachment of the developing embryo to the lining of the uterus.

Question: Name any two sexually transmitted infections (STIs).

Answer:  Gonorrhoea and syphilis.

Question: What is the function of the placenta?

Answer:  The placenta supplies oxygen and nutrients to the developing embryo and helps remove its waste products.

Question: Name one surgical method of contraception in males and females.

Answer: Male: Vasectomy and Female: Tubectomy.

Short Question and Answer :

Question: Differentiate between asexual reproduction and sexual reproduction.

Answer: The difference between Asexual Reproduction and Sexual Reproduction

Asexual Reproduction	Sexual Reproduction
(a) Only one parent is involved.	(a) Two parents are usually involved.
(b) Gametes are not formed.	(b) Gametes are formed.
(c) It involves no fusion of gametes.	(c) It involves the fusion of male and female gametes.
(d) The offspring are genetically identical to the parent.	(d) The offspring are genetically different from the parents.
Examples: Amoeba ,Hydra and Yeast.	Examples: Humans and Frog .

Question: Differentiate between binary fission and multiple fission.

Answer: The different between binary fission and multiple fission.

Binary Fission	Multiple Fission
(a) In this process, the parent cell divides into two daughter cells.	(a) In this process, the parent cell divides into many daughter cells simultaneously.
(b) The nucleus divides once, followed by the division of the cytoplasm.	(b) The nucleus divides repeatedly into many nuclei, and then the cytoplasm divides.
(c) Daughter cells are released immediately after division.	(c) Daughter cells are released only when conditions become favourable.
Examples: Amoeba, Paramecium and Leishmania	Examples: Plasmodium

Question: Describe the process of budding in hydra.  [2M SEBA 2016]

Answer: In Hydra, a small outgrowth called a bud develops on the parent's body by repeated cell division. The bud grows into a miniature Hydra, develops tentacles and eventually detaches from the parent body to become a new independent individual. This is an asexual mode of reproduction.

Q5. Why is vegetative propagation preferred for growing some plants?

Answer: Vegetative propagation is preferred because:

(i) It helps grow plants that do not produce viable seeds.

(ii) It produces new plants that are genetically similar to the parent plant and allows them to grow faster than plants grown from seeds.

Question: State two functions of the testes in human males.

Answer: The two functions of the testes in human males are:

(a) The testes produce male gametes called sperms.

(b) They secrete the male sex hormone testosterone, which helps in the development of male secondary sexual characteristics.

Question: What are the functions of the ovaries in human females?

Answer: The functions of the ovaries in human females are :

(i) The ovaries produce female gametes called ova (eggs).

(ii) They secrete hormones such as oestrogen and progesterone, which regulate reproductive development and the menstrual cycle.

Question:  Write the technique of tissue culture used by the plant breeders. [2M SEBA 2017]

Answer: In tissue culture, new plants are grown by removing tissue or separating cells from the growing tip of a plant. These cells are placed in an artificial medium where they divide rapidly to form a small group of cells called callus. The callus is then transferred to another medium containing hormones for growth and differentiation. The plantlets are finally placed in soil to grow into mature plants. This technique produces many disease-free plants from one parent and is commonly used for ornamental plants.

Question: Describe the process of fission in unicellular organisms.  [2M SEBA 2017]

Answer: Fission is a type of asexual reproduction in which a unicellular organism divides to form two or more new organisms. In binary fission, the parent cell divides into two daughter cells, as seen in Amoeba. In multiple fission, the parent cell divides into many daughter cells at the same time, as seen in Plasmodium.

Question: What is the importance of DNA copy in reproduction ? [2M 2019]

Answer: DNA copying is important in reproduction because it transfers the genetic information from parents to offspring. It ensures the basic body design of the offspring remains similar to that of the parents. However, small variations may occur during DNA copying, which help organisms adapt to changing environmental conditions and play an important role in the evolution of species.

Question: How does reproduction help in maintaining stability to the populations of a species ? [SEBA 2019]

Answer: The reproduction helps maintain the stability of a species by ensuring the continuation of its population. It produces new individuals to replace those that die. Variations produced during reproduction help some organisms survive changes in the environment, thereby maintaining the existence of the species over generations.

Question: How reproduction through spores is beneficial for an organism ? [2M2020]

Answer: The reproduction through spores is beneficial because spores are covered by a thick protective wall that helps them survive unfavourable conditions. Under favourable conditions, the spores germinate and develop into new organisms.

Question: How does spirogyra reproduce ? [2M 2020]

Answer: Spirogyra reproduces by fragmentation. When its filament breaks into smaller pieces, each fragment grows into a new individual under favourable conditions.

Question: How does menstruation occur ? [2020]

Answer:  Menstruation occurs when the egg released by the ovary is not fertilized. The thickened uterine lining slowly breaks and comes out through the vagina as blood and mucous. This cycle takes place roughly every month and is known as menstruation.

Question: How does a unisexual flower differ from a bisexual flower ? Give one example each for both the types. [2M 2021]

Answer: The difference between a unisexual flower and a bisexual flower is :

Unisexual Flower	Bisexual Flower
A flower that contains either stamens or carpels is called a unisexual flower. Example: Papaya or watermelon.	A flower that contains both stamens and carpels is called a bisexual flower. Example: Hibiscus or mustard.

Question: Give the names of two agents that help in cross-pollination. How do a seed and a fruit develop ? [2M 2021]

Answer: The names of two agents that help in cross-pollination are wind and insects.

After fertilisation, the fertilised egg (zygote) develops into an embryo and the ovule develops into a seed. The ovary develops into a fruit.

Long Question and Answer :

Question: Draw a labeled diagram of longitudinal section of an idea flower . [3M 2017]

Answer: The diagram of longitudinal section of an idea flower: 

Question: What is Pollination ? Is there any difference between pollination and fertilization ? How does self-pollination differ from cross pollination ? [3M SEBA 2020]

Answer: Pollination is the transfer of pollen grains from the anther to the stigma of a flower.

Yes. Pollination is the transfer of pollen grains from the anther to the stigma, whereas fertilisation is the fusion of the male and female gametes to form a zygote.

The difference between self-pollination and cross pollination :

Self-pollination	Cross pollination
The transfer of pollen grains from the anther to the stigma of the same flower or another flower on the same plant is called self-pollination .	The transfer of pollen grains from the anther of one flower to the stigma of a flower on another plant of the same species is called cross-pollination.

Question: Draw a labeled diagram of female reproductive system of human . [3M 2017]

Answer: The diagram of female reproductive system of human:

             

Question: What is the process of reproduction in amoeba ? What are the advantage of sexual reduction over asexual reproduction?  [3M SEBA 2018]

Answer: Amoeba reproduces asexually by the process of binary fission.

Sexual reproduction produces variations in the offspring, which help them adapt to changing environmental conditions. These variations increase the chances of survival of a species and play an important role in evolution. Therefore, sexual reproduction has an advantage over asexual reproduction, as it produces genetic variations among the offspring.

Question: Describe the process of sexual reproduction in flowering plants.  [3M SEBA 2019]

Answer: The sexual reproduction in flowering plants begins with pollination, in which pollen grains are transferred from the anther to the stigma. A pollen tube grows through the style towards the ovule. The male gamete travels through the pollen tube and fuses with the female gamete to form a zygote. This process is called fertilisation. The zygote develops into an embryo, the ovule becomes a seed, and the ovary develops into a fruit.

Question: What are sporangia ? are they involved in the reproduction of any organisms ? What do they contain that eventually can develop into a new individual ?  [2025 3M]

Answer: Sporangia are knob-like structures found in Rhizopus (bread mould) .

Yes, they are involved in reproduction.

They contain spores, which are tiny reproductive units. When these spores are released, they land on favourable surfaces and germinate to develop into a new individual (new Rhizopus) .

Question: What is variation ? How does sexual reproduction give rise to more viable variations than asexual reproduction ? Why is it beneficial to the species but not necessarily for the individual ? [2025 3M]

Answer: Variation refers to the differences in characteristics or traits among individuals of the same species.

In sexual reproduction, DNA from two parents combines and producing new combinations of traits. Therefore, it creates more variations than asexual reproduction, where offspring are almost identical to the parent.

Variations help a species survive environmental changes and increase its chances of survival. However, a variation may not always be beneficial to an individual.

Question: Describe the process of sexual reproduction in flowering plants.

Answer: In flowering plants, sexual reproduction involves pollination and fertilisation. Pollen grains from the anther are transferred to the stigma through pollination, which may be self or cross pollination. The pollen grain then germinates and forms a pollen tube that carries the male gamete to the ovule in the ovary. There, the male gamete fuses with the female gamete (egg) to form a zygote. This fusion is called fertilisation and the zygote develops into an embryo inside the seed.

Question: Explain the functions of the main parts of the human male reproductive system.

Answer: The human male reproductive system consists of testes, vas deferens, seminal vesicles, prostate gland and penis. The testes produce sperms and secrete the hormone testosterone. The vas deferens carries sperms to the urethra. The seminal vesicles and prostate gland add their secretions to make the semen, which nourishes and helps the sperms to swim. The penis delivers semen into the female's body during sexual intercourse.

Question: Describe the functions of the main parts of the human female reproductive system.

Answer: The human female reproductive system consists of ovaries, oviducts (fallopian tubes), uterus and vagina. The ovaries produce the female gamete (egg) and secrete hormones like oestrogen and progesterone. The oviducts carry the egg from the ovary to the uterus, and fertilisation takes place here. The uterus receives the fertilised egg and provides nourishment for the developing embryo. The vagina receives sperms during intercourse and serves as the birth canal during childbirth.

Question: Explain the changes that occur during puberty in human beings.

Answer: Puberty is the period during which a child’s body undergoes changes and becomes capable of reproduction. In boys, the voice deepens, facial and body hair grows and the testes start producing sperms. In girls, breasts develop, hips widen and menstruation begins. These changes are caused by sex hormones, mainly testosterone in boys and oestrogen in girls.

Question: Explain how the embryo receives nourishment inside the mother's body.

Answer: After fertilisation, the embryo gets embedded in the lining of the uterus. A special structure called the placenta develops between the embryo and the uterine wall. The placenta has villi that provide a large surface area for the exchange of food, oxygen and waste materials between the mother's blood and the embryo's blood. Thus, the embryo receives nourishment from the mother through the placenta.

---

Posted 2 weeks ago