A study found that children with light-coloured eyes are likely to have parents with light-coloured eyes. On this basis, can we say anything about whether the light eye colour trait is dominant or recessive? Why or why not?
On the basis of the above information, we cannot say that light eye colour is a dominant trait or a recessive trait. The light eye colour trait can be dominant or as well as may be recessive. If the child has LL genotype, parents could have light coloured eyes with homozygous LL genotype. And, if the child has ll genotype, parents could have light coloured eyes with homozygous ll. So, as a conclusion we cannot find that light coloured eyes traits can be dominant or recessive, for this we should have at least data of three generations.
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?
Why is sodium kept immersed in kerosene oil?
How can three resistors of resistances 2 Ω, 3 Ω, and 6 Ω be connected to give a total resistance of (a) 4 Ω, (b) 1 Ω?
Why does the Sun appear reddish early in the morning?
Two circular coils A and B are placed closed to each other. If the current in the coil A is changed, will some current be induced in the coil B? Give reason.
In the refining of silver, the recovery of silver from silver nitrate solution involved displacement by copper metal. Write down the reaction involved.
What are the environmental consequences of the increasing demand for energy? What steps would you suggest to reduce energy consumption?
What would be the consequences of a deficiency of haemoglobin in our bodies?
What can you as an individual do to reduce your consumption of the various natural resources?
Why do we apply paint on iron articles?
The kidneys in human beings are a part of the system for
(a) nutrition. (c) excretion.
(b) respiration. (d) transportation.