Class 10 Science - Chapter How do Organism Reproduce? NCERT Solutions | How does the embryo get nourishment insi

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

Draw a labelled diagram of the longitudinal section of a flower.

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

Why does menstruation occur?

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

Asexual reproduction takes place through budding in

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

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

What are the advantages of sexual reproduction over asexual reproduction?

What is the importance of DNA copying in reproduction?

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

Did Döbereiner’s triads also exist in the columns of Newlands’ Octaves? Compare and find out.

What is a good source of energy?

Why is diffusion insufficient to meet the oxygen requirements of multi-cellular organisms like humans?

What are trophic levels? Give an example of a food chain and state the different trophic levels in it.

What changes can you make in your habits to become more environment-friendly?

What is the difference between a reflex action and walking?

If a trait A exists in 10% of a population of an asexually reproducing species and a trait B exists in 60% of the same population, which trait is likely to have arisen earlier?

Why should a magnesium ribbon be cleared before burning in air?

Define the principal focus of a concave mirror.

You have been provided with three test tubes. One of them contains distilled water and the other two contain an acidic solution and a basic solution, respectively. If you are given only red litmus paper, how will you identify the contents of each test tube?

How would these advantages differ from the advantages of using a long-term perspective in managing our resources?

What are alloys?

What would you observe when zinc is added to a solution of iron(II) sulphate? Write the chemical reaction that takes place.

Explain the mechanism of the cleaning action of soaps.

The position of three elements A, B and C in the Periodic Table are shown below –

      Group 16          Group 17
            -                       -
            -                       A
            -                       -
            B                      C

(a) State whether A is a metal or non-metal.
(b) State whether C is more reactive or less reactive than A.
(c) Will C be larger or smaller in size than B?
(d) Which type of ion, cation or anion, will be formed by element A?

Metal compound A reacts with dilute hydrochloric acid to produce effervescence. The gas evolved extinguishes a burning candle. Write a balanced chemical equation for the reaction if one of the compounds formed is calcium chloride.

The autotrophic mode of nutrition requires

         (a) carbon dioxide and water.         (c) sunlight.
         (b) chlorophyll.                                (d) all of the above.

Use Mendeléev’s Periodic Table to predict the formulae for the oxides of the following elements:

    K,     C,      AI,      Si,      Ba.

Which of the following lenses would you prefer to use while reading small letters found in a dictionary?

(a) A convex lens of focal length 50 cm.
(b) A concave lens of focal length 50 cm.
(c) A convex lens of focal length 5 cm.
(d) A concave lens of focal length 5 cm.

Explain the underlying principle and working of an electric generator by drawing a labelled diagram. What is the function of brushes?