Will geographical isolation be a major factor in the speciation of a self-pollinating plant species? Why or why not?
No, geographical isolation will not be the major factor in the speciation of the self pollinating plant species because geographical isolation is the part of the reproductive isolation which occurs before the mating of the individuals. Geographical isolation is the separation of a group of related organisms by physical barriers like sea, mountain, desserts etc. In the self pollinating plants new variants or new traits are not formed, only homozygous will form, but in cross pollination variations can evolve. So, geographical isolation cannot be the major factor in the speciation of self pollinating plants.
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?
An electric oven of 2 kW power rating is operated in a domestic electric circuit (220 V) that has a current rating of 5 A. What result do you expect? Explain.
Why should curd and sour substances not be kept in brass and copper vessels?
What is the far point and near point of the human eye with normal vision?
Fresh milk has a pH of 6. How do you think the pH will change as it turns into curd? Explain your answer.
Name two safety measures commonly used in electric circuits and appliances.
Find the power of a concave lens of focal length 2 m.
We wish to obtain an erect image of an object, using a concave mirror of focal length 15 cm. What should be the range of distance of the object from the mirror? What is the nature of the image? Is the image larger or smaller than the object? Draw a ray diagram to show the image formation in this case.
In the Modern Periodic Table, which are the metals among the first ten elements?
A solar water heater cannot be used to get hot water on
(a) a sunny day. (b) a cloudy day.
(c) a hot day. (d) a windy day.
What changes would you suggest in your home in order to be environment-friendly?