How Do Organisms Reproduce?


Name the two types of germ-cells present in human beings. How do they structurally differ from each other? Give two differences.


The two types of germ-cells present in human beings are sperm and ova. The sperm of human have either X or Y chromosome. The ova always carry X chromosome. The sperm is structurally long with a tail. The ova is round in structure.


How Do Organisms Reproduce?

Q 1.

How is the process Of pollination different from fertilization ?

Q 2.

Write any two differences between binary fission and multiple fission in a tabular form as observed in cells of organisms.

Q 3.

What are the different methods of contraception?

Q 4.

What is regeneration? State a reason why a more complex organism cannot give rise to new individuals through this method.

Q 5.

Define the term puberty. List two  changes observed in girls at the time of puberty.

Q 6.

State the method used for growing rose plants.

Q 7.

Which of the following is not a pan Of the female reproductive system in human beings ?
(a) Ovary
(b) Uterus
(c) Vas deferens
(d) Fallopian tube

Q 8.

(a) In the human body what is the role of
(i) seminal vesicles, and (ii) prostate gland?
(b) List two functions performed by testis in human beings.

Q 9.

(a) Name the parts labelled A, B, C, D and E.
(b) Where do the following functions occur?
(i) Production of an egg
(ii) Fertilisation
(iii) Implantation of zygote.
(c) What happens to the lining of uterus:
(i) before release of a fertilised egg?
(ii) if no fertilisation occurs?

Q 10.

What is the role of the seminal vesicles and the prostate gland ?

Q 11.

What are the advantages of sexual reproduction over asexual reproduction?

Q 12.

Why does menstruation occur?

Q 13.

List and explain in brief three methods  of contraception.

Q 14.

How will an organism be benefited if it reproduces through spores?

Q 15.

How does reproduction help in providing stability to populations Of species?

Q 16.

State in brief the changes that take place in a fertilised egg (zygote) till birth of the child in the human female reproductive system. What happens to the egg when it is not fertilised?

Q 17.

Define the terms unisexual and bisexual giving one example of each.

Q 18.

Name the largest cell present in the human body.

Q 19.

List any three differences between pollination and fertilisation.

Q 20.

What does HIV stand for? Is AIDS an infectious disease? List any four modes of spreading AIDS.

Q 21.

Describe in brief the role of (i) testis (ii) seminal vesicle, (iii) vas deferens, (iv) ureter and (v) prostate gland in human male reproductive system.

Q 22.

State one genetically different feature between sperms and eggs of humans. What is its consequence?

Q 23.

Why is variation beneficial to the species but not necessarily for the individual?

Q 24.

How does the embryo get nourishment inside the Mother’s body?

Q 25.

What are the functions performed by the testes in human beings?

Q 26.

What is reproduction? What are its two types? Which one of the two confers new characteristics on the offsprings and how?

Q 27.

List two advantages of vegetative  reproduction practised in case of an orange plant.

Q 28.

How does growing embryo get nutrition from the mother’s blood?

Q 29.

Differentiate between ‘self-pollination’ and ‘cross-pollination’. Describe double fertilisation in plants.

Q 30.

(a) Draw a diagram showing germination of pollen on stigma of a flower.
(b) Label pollen grain, male germ- cells, pollen tube and female germ-cell in the above diagram.
(c) How is zygote formed?

Q 31.

Expand AIDS. List any four methods of prevention (control) of AIDS.

Q 32.

Draw a diagram of a human female reproductive system and label the part
(i) that produces egg
(ii) where fusion of egg and sperm take place
(iii) where zygote is implanted
What happens to human egg when it is not fertilised?

Q 33.

(a) Explain the terms:
(i) Implantation (ii) Placenta
(b) What is the average duration of human pregnancy?

Q 34.

Explain vegetative propagation with the help of two examples. List two advantages of vegetative propagation.

Q 35.

(a) Explain the role of placenta in the development of human embryo.
(b) Give example of two bacterial and two viral sexually transmitted diseases. Name the most effective contraceptive which prevents spread of such diseases.

Q 36.

Name the two types of germ-cells present in human beings. How do they structurally differ from each other? Give two differences.

Q 37.

What is the effect of DNA copying which is not perfectly accurate on the reproduction process?

Q 38.

Draw a longitudinal section of a flower and label the following parts:
(i) Part that produces pollen grain.
(ii)Part that transfers male gametes to the female gametes.
(iii) Part that is sticky to trap the pollen grain.
(iv) Part that develops into a fruit.

Q 39.

a) List any four reasons for adopting contraceptive methods.
(b) If a woman is using Copper-T, will it help in protecting her from sexually transmitted diseases? Why?  

Q 40.

With the help of suitable diagrams, explain the various steps of budding in Hydra.

Q 41.

What could be the reasons for adopting contraceptive methods?

Q 42.

List any four modes of asexual reproduction.

Q 43.

Name one sexually transmitted disease each caused due to bacterial infection and viral infection. How can these be prevented?

Q 44.

Why is DNA copying an essential part of the process of reproduction?

Q 45.

“DNA copies generated during  reproduction will be similar but may not be identical to the original.” Justify this statement.

Q 46.

Why is DNA copying an essential part of the process of reproduction?

Q 47.

List two advantages of practising vegetative propagation in plants. Select two plants raised by this method from the list given below:
Banana, Gram, Pea, Rose, Tomato, Wheat.

Q 48.

Can you think of reasons why more complex organisms cannot give rise to new individuals through regeneration?

Q 49.

Asexual reproduction takes place through budding in :
(a) Amoeba
(b) Yeast
(c) Plasmodium
(d) Leishmania.

Q 50.

How are the modes for reproduction different in unicellular and multicellular organisms ?