Class 10 Science - Chapter How do Organism Reproduce? NCERT Solutions | What could be the reasons for adopting c

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?

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

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?

Compare and contrast bio-mass and hydro electricity as sources of energy.

What is meant by saying that the potential difference between two points is 1 V?

What is the role of the acid in our stomach?

Will current flow more easily through a thick wire or a thin wire of the same material, when connected to the same source? Why?

A piece of wire of resistance R is cut into five equal parts. These parts are then connected in parallel. If the equivalent resistance of this combination is R′, then the ratio R/R′ is –

(a) 1/25        (b) 1/5        (c) 5        (d) 25

What is the function of digestive enzymes?

Use the data in Table 12.2 to answer the following –

(a) Which among iron and mercury is a better conductor?
(b) Which material is the best conductor?

A positively-charged particle (alpha-particle) projected towards west is deflected towards north by a magnetic field. The direction of magnetic field is

   (a) towards south                 (b) towards east
   (c) downward                       (d) upward

Why is the amount of gas collected in one of the test tubes in Activity 1.7 double of the amount collected in the other? Name this gas.

What are the components of the transport system in human beings? What are the functions of these components?