How Do Organisms Reproduce Class 10 Exemplar




Multiple Choice Questions:

Q-1: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)


Asexual reproduction takes place without the process of gamete formation and only one parent is needed examples include Amoeba reproduce by finery fission (division of cell into two similar cells).

Yeast, reproduce by budding (small buds develop form body wall of parent that separate and grow further).

Banana, reproduce by vegetative propogation (vegetative parts of a plant such as root, stem, etc, can produce new plants).

In dog, sexual reproduction takes place, (i.e., it involves two sexes-male and female whose gametes fuse constituting sexual reproduction).

Q-2: 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

Solution: (c)

In a flower, the parts that produce male and female gametes are anther and over respectively. Stamen is the male reproductive unit of the flower. It contains a bilobed anther at the top which produce male gametes. Filament is the stalk of the stamen that supports anther.

Pistil (carpel) is the female reproductive part of the flower. It consists of ovary (forms ovules-female gametes), stigma (receives pollen) and style (elongated tube).

Q-3: 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, fertilisation

Solution: (c)

The correct sequence of events are

Seeding (ovule develops a tough coat and converts into a seed)

4:Off spring 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)

Solution: (a)

Offsprings have greater similarity as only one parent is involved in asexual reproduction thus no gametes one former. The basis of asexual reproduction is mitosis (division of nucleus into two identical daughter nuclei). Each daughter nucleus has same genetic make up because of replication of parental DNA. The new offsprings produced are called clones.

Q-5: Characters transmitted from parents to offspring are present in

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

Solution: (d)

Characters are transmitted from parents to offspring through genes. Genes are the hereditary units of the body in living organisms. Chromosomes in the nucleus of a cell contain information for the inheritance of features from parents in the form of DNA (Deoxyribonucleic acid). This DNA contains genes.

Q-6: Characters that are transmitted from parents to offspring during reproduction show

(a) only similarities with parents

(b) only variations with parents

(c) both similarities and variations with parents

(d) neither similarities nor variations

Solution: (c)

In sexual reproduction, the offsprings are not identical to the parents or to one another. This is because the offsprings receive some genes from mother and some from father.

Because of mixing of genes on re-establishment of number of chromosome is various different combinations, the offsprings show both similarities and variations with characters of parents.

Q-7: 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

Solution: (a)

Amoeba and yeast are unicellular while Spirogyra is multicellular. But all the feature of reproduce asexually.

Q-8: In Spirogyra, asexual reproduction takes place by

(a) breaking up of filaments into smaller bits

(b) division of a cell into two cells

(c) division of a cell into many cells

(d) formation of young cells from older cells

Solution: (a)

In Spirogyra, asexual reproduction takes place by fragmentation, i.e., organism simple breaks up into smaller pieces upon maturation. Each pieces grow into new individual without forming any gametes.

Q-9: 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

Solution: (d)

Multiple fission-organism divide into many daughter cells simultaneously e.g., Plasmodium

Budding-small bud develops on the cell wall of organism that separate and grow further, e.g., yeast.

Reduction division-meiosis is described as a process of reduction division. The number of chromosomes are reduced to half.

Binary fission-organisms divide into two daughter cells e.g., Amoeba.

Q-10: 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


The correct sequence of reproductive stages in flowering plants is the formation of gametes——> fusion of gametes to form zygote———–> develops into an embryo in the ovary———> ovule develops a tough coat and converts into a seed.

Q-11: The number of chromosomes in parents and offsprings of a particular species remains constant due to

(a) doubling of chromosomes after zygote formation

(b) halving of chromosomes during gamete formation

(c) doubling of chromosomes after gamete formation

(d) halving of chromosomes after gamete formation

Solution: (b)

The number of chromosomes in parents and offsprings of a particular species remains constant due to halving of chromosome during gamete formation.

The gametes are special type of cells which contain only half the amount of DNA as compared to normal cells of organism. So, when a male gamete combines with a female gamete during sexual reproduction, then the new cell ‘zygote’ will have normal amount of DNA.

Q-12: In Rhizopus, tubular thread-like structures bearing sporangia at their tips are called

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

Solution: (b)

The thread-like structures of the bread mould, Rhizopus are called hyphae. They tiny blobs present on them which contains cells or spores are sporangia. The spores eventually develop into new Rhizopus individuals, when they come in the contachment an other most surface.

Q-13: 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

Solution: (b)

In vegetative propagation, vegetative parts of a plant such as root, stem, leaf, etc., can produce new plants. Vegetative reproduction is seen in plants like orchids, ornamental plants, grasses, banana, rose, jasmine, etc.

Q-15: Factors responsible for the rapid spread of bread mould on slices of bread are

(i) Large number f of spores

(ii) Availability of moisture and nutrients in bread

(iii) Presence of tubular branched hyphae

(iv) presence of tubular branched hyphae

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

Solution: (c)

Under favourable conditions (like damp and warm conditions, nutrients), the air-borne spores land on food, germinate and produce new plants. These spores spread into air when spore case of plant containing hundreds of spores bursts.

Q-15: Length of pollen tube depends on the distance between

(a) pollen grain and upper surface of stigma

(b) pollen grain on upper surface of stigma ovule

(c) pollen grain in anther and upper surface of stigma

(d) upper surface of stigma and lower part of style

Solution: (b)

Length of pollen tube depends on the distance between pollen grain on upper surface of stigma and ovule. A pollen grain falls on the stigma of the carpel, bursts, open and develops a pollen tube downwards through the style towards the ovule in the ovary.

Q-16: 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 fertilization they give rise to fruits

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

Solution: (d)

Flowers are the sexual reproductive organs of a plant. They are produced in angiosperms. Majority of flowers are bisexual. After fertilization, they give rise to fruits.

Q-17:Which among the following statements are true for unisexual flowers?

(i) They possess both stamen and pistil.

(ii) They posses either stamen or pistil.

(iii) They exhibit cross pollination.

(iv) Unisexual flowers possessing only stamens cannot produce fruits.

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

(c) (iii) and (iv)                     (d) (i) , (iii) and (iv)

Solution: (b)

The flowers are unisexual (papaya, watermelon) contains either stamens or carpels. Since, only one reproductive organ is present in them, they depend on cross pollination to form zygote and carpels are required for fertilization, so only one of them cannot produce fruits.

Q-18: Which among the following statements are true for sexual reproduction in flowering plants?

(i) It requires two types of gametes.

(ii) Fertilization is a compulsory event.

(iii) It always results in formation of zygote.

(iv) Offspring formed are clones.

(a) (i) and (iv)                           (b) (i), (ii) and (iv)

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

Solution: (c)

Sexual reproduction creates variation in organism. So, clones cannot be produced through it. Clones are identical copy of parent organism. Sexual reproduction reacts two type of gametes, i.e., male and female to form zygote after fertilization.

Q-19: In the figure the parts A, B and C are sequentially

Image- p-130, q-19

(a) cotyledon, plumule and radical                (b) plumule, radical and cotyledon

(c)plumule, cotyledon and radical                 (d) radical, cotyledon and plumule

Image- p-130, q-19

Solution: (c)

Plumule ‘A’ grows into shoots, cotyledon ‘B’ stores food and radical ‘C’ grow into roots.

Q-20: Offspring formed as a result of sexual reproduction exhibit more variations because

(a) sexual reproduction is a lengthy process

(b) genetic material comes from two parents of the same species

(c) genetic material comes from two parents of different species

(d) genetic material comes from many parents

Solution: (b)

Sexual reproduction occurs between two parents of the same species, not different species (Also, refer to Q. 6) thus creates new combinations of variants and each combination is novel.

Q-21:Reproduction is essential for living organisms to order to

(a) keep the individual organism alive

(b) fulfill their energy requirement

(c) maintain growth

(d) continue to species generation after generation

Solution: (d)

Reproduction is not essential for the survival of an individual, but it is an important function of a living being as it helps an organism to perpetuate its own kind.

Through this process, new individuals are produced, that grow and reproduce again, so as to continue the species generation after generation. Reproduction is a process to maintain the progeny of an organism.

Q-22: During adolescence, several changes occur in the human body. Mark one change associated with sexual maturation in boys

(a) loss of milk teeth                             (b) increase in height

(c) cracking of voice                              (d) weight gain

Solution: (c)

Cracking of voice is associated with second maturation is boys which occurs during adolescence. During teenage a new set of changes occurs in boys and girls. In boys there changes includes-growth of hairs on face, cracking of voice etc.

Loss of milk teeth, increase in height and weight gain are the normal process of growth in both boys and girls as the body grows older.

Q-23: In human females, an event that reflects onset of reproductive phase is

(a) growth of body                          (b) changes in hair pattern

(c) change in voice                          (d) menstruation


In early teenage girls should, breast size increased, with darkening of the skin of nipples at the tip of breasts. Also, girls begin to menstruate at around this time. In human females, this reflects onset of reproductive phase.

Q-24: In human males, the testes lie in the scrotum, because it helps in the

(a) process of mating                       (b) formation of sperm

(c) easy transfer of gametes           (d) All of these

Solution: (b)

Formation of germ cells or sperms takes place in the testes and it lies in the scrotum. In the scrotum (outside the abdominal cavity), the temperature is about 30C lower than the temperature of the body. Testes lie in the scrotum because the sperm formation require a lower temperature than the normal body temperature.

Q-25: Which among the following is not the function of tests at puberty?

(i) Formation of germs 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)

Solution: (c)

Development of placenta and secretion of estrogen are related to female reproductive system, hence are not the function of testes at puberty.

Q-26: The correct sequence of organs in the male reproductive system form transport of sperms is

(a) testis vas—> deferens—-> urethra      

(b) testis —->  ureter —-> urethra

(c) testis —->  urethra —->  ureter                           

(d) testis —->  vas deferens —->  ureter

Solution: (a)

Sperms formed in testis are delivered through the vas deferens which joins with another tube called urethra coming from the urinary bladder.

Q-27: Which among the following diseases is not sexually transmitted?

(a) Syphilis                               (b) Hepatitis

(c) HIV-AIDS                           (d) Gonorrhea

Solution: (b)

The diseases which are spread by sexual contact with in infected person are called sexually. Transmitted Diseasses or STC, e.g., gonorrhea, syphilis and AIDS. Hepatitis is a water borne viral disease which affects liver.