Choose the most appropriate answer: (a) | Class 8 Science Chapter Reproduction in Animals, Reproduction in Animals NCERT Solutions

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

Indicate whether the following statements are True (T) or False (F):
(a) Oviparous animals give birth to young ones.                                    ( )
(b) Each sperm is a single cell.                                                              ( )
(c) External fertilization takes place in frog.                                           ( )
(d) A new human individual develops from a cell called gamete.          ( )
(e) Egg laid after fertilization is made up of a single cell.                       ( )
(f) Amoeba reproduces by budding.                                                       ( )
(g) Fertilization is necessary even in asexual reproduction.                  ( )
(h) Binary fission is a method of asexual reproduction.                         ( )
(i) A zygote is formed as a result of fertilization.                                    ( )
(j) An embryo is made up of a single cell.                                              ( )

In which female reproductive organ does the embryo get embedded?

Describe the process of fertilization in human beings.

How is an embryo developed?

How are test tube babies born?

Give the full form of IVF.

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.

Differentiate between internal fertilization and external fertilization.

Explain the importance of reproduction in organisms.

Describe with the help of a diagram an instrument which can be used to detect a charged body.

Sketch larynx and explain its function in your own words.

Arrange the following boxes in proper order to make a flow chart of sugarcane crop production.

Make a labelled diagram of a candle flame.

The following Table shows the total power shortage in India from 1991– 1997. Show the data in the form of a graph. Plot shortage percentage for the years on the Y-axis and the year on the X-axis.

Describe the construction of a kaleidoscope.

Make sketches of animal and plant cells. State three differences between them.

What is a constellation? Name any two constellations.

Complete the crossword with the help of clues given below:
Across
1. This is necessary for photosynthesis.
3. Term for component present in the cytoplasm.
6. The living substance in the cell.
8. Units of inheritance present on the chromosomes.

Down
1. Green plastids.
2. Formed by collection of tissues.
4. It separates the contents of the cell from the surrounding medium.
5. Empty structure in the cytoplasm.
7. A group of cells.

Make a sketch of the human nerve cell. What function do nerve cells perform?

What is menstruation? Explain.

Do all the stars in the sky move? Explain.

Should the handle and bristles of a tooth brush be made of the same material? Explain your answer.

Suggest three measures to protect ourselves from lightning.

Explain how the use of CNG in automobiles has reduced pollution in our cities.

Fill in the blanks:

(a) Microorganisms can be seen with the help of a ____________.
(b) Blue green algae fix __________ directly from air to enhance fertility of soil.
(c) Alcohol is produced with the help of __________.
(d) Cholera is caused by __________.

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

‘Avoid plastics as far as possible’. Comment on this advice.

Select the correct word from the following list and fill in the blanks.
                 float, water, crop, nutrients, preparation

(a) The same kind of plants grown and cultivated on a large scale at a place is called _____________.
(b) The first step before growing crops is _____________ of the soil.
(c) Damaged seeds would _____________ on top of water.
(d) For growing a crop, sufficient sunlight and _____________ and _____________ from the soil are essential.

A blacksmith hammers a hot piece of iron while making a tool. How does the force due to hammering affect the piece of iron?