Class 10 Science - Chapter Control and Coordination NCERT Solutions | What is the difference between a reflex

Draw the structure of a neuron and explain its function.

Which signals will get disrupted in case of a spinal cord injury?

How does chemical coordination take place in animals?

Compare and contrast nervous and hormonal mechanisms for control and coordination in animals.

Why is the use of iodised salt advisable?

The brain is responsible for

(a) thinking.
(b) regulating the heart beat.
(c) balancing the body.
(d) all of the above.

How do we detect the smell of an agarbatti (incense stick)?

How do auxins promote the growth of a tendril around a support?

Which part of the brain maintains posture and equilibrium of the body?

How does our body respond when adrenaline is secreted into the blood?

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 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?

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 curd and sour substances not be kept in brass and copper vessels?

What are the limitations of extracting energy from—

   (a) the wind?          (b) waves?          (c) tides?

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?

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

Define 1 dioptre of power of a lens.

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

Describe the structure and functioning of nephrons.

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?