What is a gene? (AI 2014)
A gene is a piece of DNA located on a chromosome that controls the synthesis of a certain protein that controls a particular trait or characteristic of an organism.
Name the information source for making proteins in the cells. (Delhi 2014)
The information needed to make proteins is found in the deoxyribonucleic acid (DNA) found in the chromosomes of the cell nucleus.
A Mendelian experiment consisted of breeding pea plants bearing violet flowers with pea plants bearing white flowers. What will be the result in F1 progeny? (AI 2018)
According to the Mendelian experiment, violet colour (VV) is a dominant trait while white colour (vv) is a recessive trait. Hence, the colour of the flower in F1 progeny will be violet (Vv).
Assertion (A) : The sex of a child in human beings will be determined by the type of chromosome he/she inherits from the father. Reason (R) : A child who inherits ‘X’ chromosome from his father would be a girl (XX), while a child who inherits a ‘Y’ chromosome from the father would be a boy (XY). (a) Both (A) and (R) are true and (R) is the correct explanation of the assertion (A). (b) Both (A) and (R) are true, but (R) is not the correct explanation of the assertion (A). (c) (A) is true, but (R) is, false. (d) (A) is false, but (R) is true. (AI 2020)
(a) Both (A) and (R) are true and (R) is the correct explanation of the assertion (A).
“Only variations that confer an advantage to an individual organism will survive in a population.” Justify this statement. (Foreign 2011)
Variations are structural, functional, or behavioural variations from the established norms in living things. Variations that are inherited take a role in evolution. Darwin proposed that individuals with advantageous variants are weeded out by natural selection. Such an organism will endure, multiply more, and create more offspring. As a result, valuable variants develop throughout nature.
All the variations in a species do not have equal chances of survival. Why? (Foreign 2014)
In the environment they live in, not all varieties have an equal chance of surviving. Different people might benefit in different ways depending on the types of variations. The organisms that are best suited to their environment will survive.
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?
It is true that only differences provide individuals of organisms a chance to live in a group. For instance, if bacteria find themselves in a situation where the ambient temperature suddenly rises, changes that boost their heat resistance can be quite helpful for survival. This will determine whether the bacteria survives or perishes.
How is the equal genetic contribution of male and female parents ensured in the progeny?
By inheriting an equal number of chromosomes from both parents, kids are guaranteed to have genetic contributions from both male and female parents. Chromosomes come in 23 pairs, however not all of them are coupled. The 22 pairings are known as autosomes, while the final pair, which consists of one pair, is known as the …
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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?
Because of the following factors, sexual reproduction leads to numerous viable variations: (a) A mistake in DNA copying (though it was rare) At the moment sex cells develop, paternal and maternal chromosomes are randomly segregated. (c) When gametes are formed, homologous chromosomes exchange genetic material. (d) Variations accumulated as a result of reproduction over many …
What evidence do we have for the origin of life from inanimate matter?
The experiment carried out in 1953 by Stanley L. Miller and Harold C. Urey proved that life originated from inanimate elements. They made an artificial atmosphere that resembled that of the early planet; it contained ammonia, hydrogen, and other gases believed to have existed during the prehistoric era of the world. The temperature of this …
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