A Mendelian experiment consisted of breeding tall pea plants bearing violet flowers with short pea plants bearing white flowers. The progeny all bore violet flowers, but almost half of them were short. This suggests that the genetic make-up of the tall parent can be depicted as
(a) TTWW
(b) TTww
(c) TtWW
(d) TtWw
(c) TtWW
According to the law of dominance, Mendel showed that the one allele is dominant over the another one (expressed allele is known as dominant allele or unexpressed one is recessive). As shown in this question, the all progeny bears violet flowers but half of them are short, this means that the violet colour flowers are dominant and the dwarf flower which contains white flower is a recessive trait.
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 gap between two neurons is called a
(a) dendrite.
(b) synapse.
(c) axon.
(d) impulse.
Which part of the brain maintains posture and equilibrium of the body?
What are the different ways in which glucose is oxidised to provide energy in various organisms?
What would be the consequences of a deficiency of haemoglobin in our bodies?
Do basic solutions also have H+(aq) ions? If yes, then why are these basic?
How does binary fission differ from multiple fission?
What is an homologous series? Explain with an example.
Why do you think that there should be equitable distribution of resources? What forces would be working against an equitable distribution of our resources?
Why do ionic compounds have high melting points?
What does one mean by exothermic and endothermic reactions? Give examples.