The correct option is (A) : Natural selection
Because bacteria can evolve resistance to streptomycin through a process known as natural selection, bacteria can proliferate in a solution containing streptomycin. Random mutations take place in the bacterium throughout this process, which leads to the development of antibiotic resistance. This allows it to keep growing in the medium. When under stress, such as when there is a nutritional shortage, induced mutation takes place. A population is split in half and reproductively separated from the other half through the process of reproductive isolation. Genetic diversity in a population is the product of genetic drift, which fixes harmful mutations. So, "natural selection" is the right response.
The given graph shows the range of variation among population members, for a trait determined by multiple genes. If this population is subjected to disruptive selection for several generations, which of the following distributions is most likely to result?
Read the following passage and answer the questions that follow. According to evolutionary theory, every evolutionary change involves the substitution of a new gene for the old one and the new allele arises from the old one. Continuous accumulation of changes in the DNA coding for proteins leads to evolutionary differences. The chemical composition of DNA is basically the same in all living beings, except for differences in the sequence of nitrogenous bases. Given below are percentage relative similarities between human DNA and DNA of other vertebrates:
(a) What is the term used for the substitution of a new gene for the old one and the new allele arising from the old one during evolutionary process?
(b) Which one of the following holds true for the data provided in the above table?
(c) [(i)] To which category of evolution (divergent or convergent) does the following relationship belong? Justify your answer.
Human and Rhesus Monkey
OR
[(ii)] Differentiate between Convergent and Divergent evolution.
Which of the following microbes is NOT involved in the preparation of household products?
A. \(\textit{Aspergillus niger}\)
B. \(\textit{Lactobacillus}\)
C. \(\textit{Trichoderma polysporum}\)
D. \(\textit{Saccharomyces cerevisiae}\)
E. \(\textit{Propionibacterium sharmanii}\)
A sphere of radius R is cut from a larger solid sphere of radius 2R as shown in the figure. The ratio of the moment of inertia of the smaller sphere to that of the rest part of the sphere about the Y-axis is :
Predict the major product $ P $ in the following sequence of reactions:
(i) HBr, benzoyl peroxide
(ii) KCN
(iii) Na(Hg), $C_{2}H_{5}OH$
AB is a part of an electrical circuit (see figure). The potential difference \(V_A - V_B\), at the instant when current \(i = 2\) A and is increasing at a rate of 1 amp/second is:
Charles Darwin - was a British naturalist who proposed the theory of biological evolution by natural selection. Darwin derived evolution as "descent with modification," the idea that species change gradually, give rise to new species and share a common ancestor. Darwin had proposed natural selection - the mechanism for evolution. Because resources are short in nature, organisms with heritable traits that favor survival and reproduction will lean to leave more offspring than their peers, causing the traits to rise in frequency over generations. The consequence of natural selection on populations is to become adapted, or increasingly well-suited, to their environments steadily. Natural selection entirely depends on the environment and needs existing heritable variation in a group.
Read More: Types of Natural Selection