Class 10 Science - Chapter Heredity and Evolution NCERT Solutions | How is the equal genetic contribution of

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?

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

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

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?

The anther contains

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

Redraw the circuit of Question 1, putting in an ammeter to measure the current through the resistors and a voltmeter to measure the potential difference across the 12 Ω resistor. What would be the readings in the ammeter and the voltmeter?

Why do you think the noble gases are placed in a separate group?

How is the process of pollination different from fertilisation?

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

Draw a labelled diagram of the longitudinal section of a flower.

Find out, from Table 10.3, the medium having highest optical density. Also find the medium with lowest optical density.

     Table 10.3 Absolute refractive index of some material media

How does the embryo get nourishment inside the mother’s body?

The kidneys in human beings are a part of the system for

   (a) nutrition.                  (c) excretion.
   (b) respiration.              (d) transportation.

How is the concentration of hydronium ions (H₃O⁺) affected when a solution of an acid is diluted?