Class 10 Science - Chapter Life Processes NCERT Solutions | Why is diffusion insufficient to meet th

How is the amount of urine produced regulated?

What criteria do we use to decide whether something is alive?

What are the different ways in which glucose is oxidised to provide energy in various organisms?

The breakdown of pyruvate to give carbon dioxide, water and energy takes place in

        (a) cytoplasm.               (c) chloroplast.
        (b) mitochondria.           (d) nucleus.

What are the differences between autotrophic nutrition and heterotrophic nutrition?

What are outside raw materials used for by an organism?

What are the components of the transport system in highly organised plants?

What would be the consequences of a deficiency of haemoglobin in our bodies?

What advantage over an aquatic organism does a terrestrial organism have with regard to obtaining oxygen for respiration?

Where do plants get each of the raw materials required for photosynthesis?

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

What is a good source of energy?

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?

What is the importance of DNA copying in reproduction?

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?

Show how you would connect three resistors, each of resistance 6 Ω, so that the combination has a resistance of (i) 9 Ω, (ii) 4 Ω.

Explain the following.

(a) Why is the tungsten used almost exclusively for filament of electric lamps?
(b) Why are the conductors of electric heating devices, such as bread-toasters and electric irons, made of an alloy rather than a pure metal?
(c) Why is the series arrangement not used for domestic circuits?
(d) How does the resistance of a wire vary with its area of cross-section?
(e) Why are copper and aluminium wires usually employed for electricity transmission?

What is a good source of energy?

Give the names of two energy sources that you would consider to be exhaustible. Give reasons for your choices.

Why is sodium kept immersed in kerosene oil?

What is the need for a system of control and coordination in an organism?

How much energy is given to each coulomb of charge passing through a 6 V battery?

Why are coils of electric toasters and electric irons made of an alloy rather than a pure metal?

Nitrogen (atomic number 7) and phosphorus (atomic number 15) belong to group 15 of the Periodic Table. Write the electronic configuration of these two elements. Which of these will be more electronegative? Why?

In the electrolytic refining of a metal M, what would you take as the anode, the cathode and the electrolyte?