Class 8 Science - Chapter Reproduction in Animals NCERT Solutions | Give two difference between a zygote and

What is metamorphosis? Give examples.

Define asexual reproduction. Describe two methods of asexual reproduction in animals.

How are test tube babies born?

Complete the cross-word puzzle using the hints given below

Across
    1. The process of the fusion of the gametes.
    6. The type of fertilization in hen.
    7. The term used for bulges observed on the sides of the body of Hydra.
    8. Eggs are produced here.

Down
    2. Sperms are produced in these male reproductive organs.
    3. Another term for the fertilized egg.
    4. These animals lay eggs.
    5. A type of fission in amoeba.

How are babies produced through IVF technique? What are such babies called?

Differentiate between internal fertilization and external fertilization.

Describe the process of fertilization in human beings.

In which female reproductive organ does the embryo get embedded?

How is an embryo developed?

Explain the importance of reproduction in organisms.

Which of the following can be beaten into thin sheets?
  (a) Zinc     (b) Phosphorus     (c) Sulphur     (d) Oxygen

Fill in the blanks
(a) Most liquids that conduct electricity are solutions of , ______________ and ______________.
(b) The passage of an electric current through a solution causes ______________ effects.
(c) If you pass current through copper sulphate solution, copper gets deposited on the plate connected to the terminal of the battery.
(d) The process of depositing a layer ofany desired metal on another material by means of electricity is called .

Give two examples each of situations in which you push or pull to change the state of motion of objects.

Fill in the blanks:
(a) Friction opposes the _____________ between the surfaces in contact with each other.
(b) Friction depends on the _____________ of surfaces.                                                                                                                                                                      (c) Friction produces __________.
(d) Sprinkling of powder on the carrom board ________ friction.
(e) Sliding friction is ___________ than the static friction.

List conditions under which combustion can take place.

Indicate whether the following statements are True (T) or False (F).
(a) Unicellular organisms have one-celled body. (T/F)
(b) Muscle cells are branched. (T/F)
(c) The basic living unit of an organism is an organ. (T/F)
(d) Amoeba has irregular shape. (T/F)

Which of the following cannot be charged easily by friction?
(a) A plastic scale
(b) A copper rod
(c) An inflated balloon
(d) A woollen cloth.

Fill in the blanks:
(a) A place where animals are protected in their natural habitat is called                  .
(b) Species found only in a particular area is known as                          .
(c) Migratory birds fly to far away places because of                     changes.

Suppose you are in a dark room. Can you see objects in the room? Can you see objects outside the room. Explain.

What are the different ways in which water gets contaminated ?

Explain the difference between the thermoplastic and thermosetting plastics.

What is the term used for secretions of endocrine glands responsible for changes taking place in the body?

Explain why a charged balloon is repelled by another charged balloon whereas an uncharged balloon is attracted by another charged balloon?

It is difficult to burn a heap of green leaves but dry leaves catch fire easily. Explain.

Prepare a Table having two columns depicting names of endocrine glands and hormones secreted by them.

Write notes on—
(a) Adam’s apple.
(b) Secondary sexual characters.
(c) Sex determination in the unborn baby.

When the free ends of a tester are dipped into a solution, the magnetic needle shows deflection. Can you explain the reason?

Answer in brief:
(a) Why should we conserve biodiversity?
(b) Protected forests are also not completely safe for wild animals. Why?
(c) Some tribals depend on the jungle. How?
(d) What are the causes and consequences of deforestation?
(e) What is Red Data Book?
(f) What do you understand by the term migration?

Name the microorganisms which can fix atmospheric nitrogen in the soil.

Write a paragraph in your own words on each of the following.
  (a) Preparation of soil                 (b) Sowing
  (c) Weeding                                (d) Threshing