Class 10 Science - Chapter Life Processes NCERT Solutions | What are the necessary conditions for au

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

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?

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?

Define the principal focus of a concave mirror.

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?

In the Modern Periodic Table, which are the metals among the first ten elements?

The magnification produced by a plane mirror is +1. What does this mean?

Imagine that you are sitting in a chamber with your back to one wall. An electron beam, moving horizontally from back wall towards the front wall, is deflected by a strong magnetic field to your right side. What is the direction of magnetic field?

You must have seen tarnished copper vessels being cleaned with lemon or tamarind juice. Explain why these sour substances are effective in cleaning the vessels.

The gap between two neurons is called a

(a) dendrite.
(b) synapse.
(c) axon.
(d) impulse.

An electric lamp of 100 Ω, a toaster of resistance 50 Ω, and a water filter of resistance 500 Ω are connected in parallel to a 220 V source. What is the resistance of an electric iron connected to the same source that takes as much current as all three appliances, and what is the current through it?

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

    K,     C,      AI,      Si,      Ba.

What is the principle of an electric motor?