Only variations that confer an advantage to an individual organism will survive in a population. Do you agree with this statement? Why or why not?
Variations are the difference among the individuals of species or their offsprings. We are agreeable to this statement that only variations can confer an advantage to an individual organism that will survive in a population. Not all living organisms have equal chances of survival in the environment. The living organisms must change their characters or adapt their characters according to the changing environment, and those who will not adapt, they will not survive. So, the chances of survival only depend on the variations in environment.
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?
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.
An object is placed at a distance of 10 cm from a convex mirror of focal length 15 cm. Find the position and nature of the image.
In the electrolytic refining of a metal M, what would you take as the anode, the cathode and the electrolyte?
Why is respiration considered an exothermic reaction? Explain.
Which part of the brain maintains posture and equilibrium of the body?
What is the role of the acid in our stomach?
Compute the heat generated while transferring 96000 coulomb of charge in one hour through a potential difference of 50 V.
How does the electronic configuration of an atom relate to its position in the Modern Periodic Table?
A shiny brown coloured element ‘X’ on heating in air becomes black in colour. Name the element ‘X’ and the black coloured compound formed.
Imagine that you are sitting in a chamber with your back to one wall. An electron beam, moving horizontally from back wall towards the front wall, is deflected by a strong magnetic field to your right side. What is the direction of magnetic field?