Class 10 Science - Chapter Control and Coordination NCERT Solutions | What is the need for a system of control

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?

How is oxygen and carbon dioxide transported in human beings?

Compare the power used in the 2 Ω resistor in each of the following circuits:

(i) a 6 V battery in series with 1 Ω and 2 Ω resistors, and (ii) a 4 V battery in parallel with 12 Ω and 2 Ω resistors.

Where should an object be placed in front of a convex lens to get a real image of the size of the object?

(a) At the principal focus of the lens
(b) At twice the focal length
(c) At infinity
(d) Between the optical centre of the lens and its principal focus.

A convex lens forms a real and inverted image of a needle at a distance of 50 cm from it. Where is the needle placed in front of the convex lens if the image is equal to the size of the object? Also, find the power of the lens.

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

Write equations for the reactions of

   (i) iron with steam
   (ii) calcium and potassium with water.

Fresh milk has a pH of 6. How do you think the pH will change as it turns into curd? Explain your answer.

Explain why the planets do not twinkle.

The anther contains

(a) sepals.
(b) ovules.
(c) pistil.
(d) pollen grains.

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