Class 10 Science - Chapter Heredity and Evolution NCERT Solutions | Why are human beings who look so differe

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

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

A man with blood group A marries a woman with blood group O and their daughter has blood group O. Is this information enough to tell you which of the traits – blood group A or O – is dominant? Why or why not?

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?

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?

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

Compare and contrast fossil fuels and the Sun as direct sources of energy.

How does chemical coordination take place in animals?

Explain the mechanism of the cleaning action of soaps.

You are given kerosene, turpentine and water. In which of these does the light travel fastest? Use the information given in Table 10.3.

Which of the following terms does not represent electrical power in a circuit?

(a) I²R          (b) IR²          (c) VI          (d) V²/R

Name two energy sources that you would consider to be renewable. Give reasons for your choices.

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

One-half of a convex lens is covered with a black paper. Will this lens produce a complete image of the object? Verify your answer experimentally. Explain your observations.

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