Class 10 Science - Chapter Heredity and Evolution NCERT Solutions | A man with blood group A marries a woman

Outline a project which aims to find the dominant coat colour in dogs.

How is the sex of the child determined in human beings?

How do Mendel’s experiments show that traits are inherited independently?

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?

Explain how sexual reproduction gives rise to more viable variations than asexual reproduction. How does this affect the evolution of those organisms that reproduce sexually?

Explain the terms analogous and homologous organs with examples.

How do Mendel’s experiments show that traits may be dominant or recessive?

How does the creation of variations in a species promote survival?

Will geographical isolation be a major factor in the speciation of an organism that reproduces asexually? Why or why not?

Why are traits acquired during the life-time of an individual not inherited?

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?

What is the importance of DNA copying in reproduction?

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?

An object 5 cm in length is held 25 cm away from a converging lens of focal length 10 cm. Draw the ray diagram and find the position, size and the nature of the image formed.

What is the role of the seminal vesicles and the prostate gland?

What are the two properties of carbon which lead to the huge number of carbon compounds we see around us?

People use a variety of methods to wash clothes. Usually after adding the soap, they ‘beat’ the clothes on a stone, or beat it with a paddle, scrub with a brush or the mixture is agitated in a washing machine. Why is agitation necessary to get clean clothes?

What will happen if a solution of sodium hydrocarbonate is heated? Give the equation of the reaction involved.

Why do HCl, HNO₃, etc., show acidic characters in aqueous solutions while solutions of compounds like alcohol and glucose do not show acidic character?

What will happen if we kill all the organisms in one trophic level?

What do you mean by a precipitation reaction? Explain by giving examples.

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

An atom has electronic configuration 2, 8, 7.

   (a)  What is the atomic number of this element?
   (b)  To which of the following elements would it be chemically similar? (Atomic numbers are given in parentheses.)
          N(7)      F(9)      P(15)      Ar(18)