Answer : (a)

Answer : (a)

Answer : (c)

Answer : (d)

correct

Frequency of dominant allele (say p) = 0.4 Frequency of recessive allele (say q) = 1 – 0.4 = 0.6 ∴ Frequency of homozygous dominant individuals (AA) = p2 = (0.4)2 = 0.16 Frequency of heterozygous individuals (Aa) = 2pq = 2(0.4)(0.6) = 0.48 Frequency of homozygous recessive individuals (aa) = q2 = (0.6)2 = 0.36 Answer : (c)

The same structure developed along different directions due to adaptations to different needs. This is divergent evolution and these structures are homologous. Homology indicates common ancestry. Examples are vertebrate hearts or brains and forebrain. Eye of octopus, bat and man are examples of analogous organs showing convergent evolution. Answer : (d)

Bats, Cheetah and human (all mammals) share similarities in the pattern of bones of forelimbs. Though these forelimbs perform different functions in these animals, they have similar anatomical structure. Hence, in these animals, the same structure developed along different directions due to adaptations to different needs. This is divergent evolution and these structures are homologous. Answer : (c)

In 1953, S.L. Miller, an American scientist created similar conditions in a laboratory scale. He created electric discharge in a closed flask containing CH4, H2, NH3 and water vapour at 800°C Answer : (c)

According to Darwinism, fossils of organisms found in South America resemble fossils of Africa and Australia. Answer : (d)

Oparin of Russia and Haldane of England proposed that the first form of life could have come from pre-existing non-living organic molecules (e.g. RNA, protein, etc.) and that formation of life was preceded by chemical evolution. (iv)-(c). Hugo deVries based on his work on evening primrose brought forth the idea of mutations – large difference arising suddenly in a population. (iii)-(d). French naturalist Lamarck had said that evolution of life forms had occurred but driven by use and disuse of organs. (ii)-a. Darwinism is a theory of biological evolution developed by the English naturalist Charles Darwin (1809–1882) and others, stating that all species of organisms arise and develop through the natural selection of small, inherited variations that increase the individual's ability to compete, survive, and reproduce. (i)-b. Answer : (a)

To Cuvier, the difference in fossils from different strata were evidences for local catastrophic events such as droughts or floods was the first to demonstrate that the different strata of rock in the Paris basin each had its own mammal fauna. Furthermore, he showed that the lower a stratum was, the more different its fossil animals were from species living in the present. Yet Cuvier rejected the idea of organic evolution. He was an essentialist, convinced that plants and animals of all types were created for their particular roles and places in the world's environment, and that they were unchanging throughout their existence. There was no scale of perfection, in Cuvier's view, because each animal was perfectly adapted to its position in the natural world. He could see no evidence for a steady increase in complexity or perfection as claimed by those who believed in a "great chain of being." He said, catastrophic events had killed off all members of some species, and their fossils would no longer be seen in the rocks. Subsequently, he believed, the old species were replaced by new ones that repopulated Earth. Answer : (c)

Answer : (a)

Lamarck had said that evolution of life forms had occurred but driven by use and disuse of organs. He gave the examples of Giraffes who in an attempt to forage leaves on tall trees had to adapt by elongation of their necks. The development of flightless brids like an ostrich from flying ancestors is considered due to continued disuse of wings as they were found in well-protected areas with plenty of food. Weak progeny of Nobel laureate cannot be explained by lamarckism. Answer : (c)

During his journey Darwin went to Galapagos Islands. There he observed an amazing diversity of creatures. The process of evolution of different species in a given geographical area starting from a point and literally radiating to other areas of geography (habitats) is called adaptive radiation. Answer : (b)

Carbon-14 has a half-life of 5,730 ± 40 years—i.e., half the amount of the radioisotope present at any given time will undergo spontaneous disintegration during the succeeding 5,730 years. Answer : (c)

Archaeopteryx was first described as the 'missing link' between reptiles and birds in 1861 – and is now regarded as the link between dinosaurs and birds Answer : (b)

All the varieties of finches, Darwin conjectured, evolved on the island itself. From the original seed-eating features, many other forms with altered beaks arose, enabling them to become insectivorous and vegetarian finches. These finches orignated from south america mainland and radiating to Galapagos island. This process of evolution of different species in a given geographical area starting from a point and literally radiating to other areas of geography (habitats) is called adaptive radiation. Answer : (a)

Jack Hills, Australia, where rocks were found to contain the oldest known minerals on Earth, a 4.4 billion-year-old zircon. Answer : (c)

Phenomenon in which, the same structure developed along different directions due to adaptations to different needs. This is divergent evolution and these structures are homologous. Answer : (c)

Genetic drift describes random fluctuations in the numbers of gene variants in a population. Genetic drift takes place when the occurrence of variant forms of a gene, called alleles, increases and decreases by chance over time. Answer : (b)

Fossil found in Mandla district belongs to late jurrasic or cretaceous era. Discovery of 65-million-year-old dinosaur eggs was done . Fossil of this species was never before seen in India. Answer : (c)

The theory of recapitulation, also called the biogenetic law or embryological parallelism states that each embryo's developmental stage represents an adult form of an evolutionary ancestor. Answer : (b)

Natural selection is a process in which heritable variations enabling better survival are enabled to reproduce and leave greater number of progeny. It is main reason of evolution. Answer : (a)

Oparin suggested chemogeny i.e., chemical origin of life. They suggested that from simple compounds like methane, ammonia, complex organic compounds wew fromed gradually. Coacervates were non living colloidal aggregates of organic molecules. It was experimentally formed by Stanley Miller and Harold Urey. Answer : (d)

Evolution is the change in the characteristics of a species over several generations and relies on the process of natural selection. Darwin believed that continuous and useful variations constitute the raw material of evolution. Answer : (c)

Mesozoic is the second-to-last era of Earth's geological history, lasting about 252 to 66 million years ago. Mesozoic is also called the Age of Reptiles Answer : (a)

A bimodal distribution is a set of data that has two peaks (modes). The “bi” in bimodal distribution refers to “two” and modal refers to the peaks The normal distribution is a bell-shaped, symmetrical distribution in which the mean, median and mode are all equal In a skewed (unbalanced, lopsided) distribution, the mean is farther out in the long tail than is the median. Answer : (d)

Oparin of Russia and Haldane of England proposed that the first form of life could have come from pre-existing non-living organic molecules (e.g. RNA, protein, etc.) and that formation of life was preceded by chemical evolution, i.e., formation of diverse organic molecules from inorganic constituents. The conditions on earth were – high temperature, volcanic storms, reducing atmosphere containing CH4, NH3, etc. Answer : (a)

Fitness is the end result of the ability to adapt and get selected by nature and hence called, “Survival of the fittest through natural selection. Fitness is the potentiality of the selection and the organism’s response to it through genetic means. The stress of the environment in high altitude is to tide over “ hypoxia” through broadening their chests and increased volume of the lungs to utilize available less oxygen in more effective way through adaptation. Answer : (c)

The Gymnosperms and first toothed birds originated during the late Paleozoic era but flourished very well during early Mesozoic era. Triassic is early mesozoic era. Answer : (c)

Answer : (d)

Answer : (a)

Mutations are the ultimate source of genetic variation. deVries believed mutation caused speciation and hence called it saltation (single step large mutation). Answer : (a)

In allopatric speciation, groups from an ancestral population evolve into separate species due to a period of geographical separation. Answer : (a)

Answer : (c)

Oparin of Russia and Haldane of England proposed that the first form of life could have come from pre-existing non-living organic molecules (e.g. RNA, protein, etc.) and that formation of life was preceded by chemical evolution, i.e., formation of diverse organic molecules from inorganic constituents. The conditions on earth were – high temperature, volcanic storms, reducing atmosphere containing CH4, NH3, etc. In 1953, S.L. Miller, an American scientist created similar conditions in a laboratory scale. He created electric discharge in a closed flask containing CH4, H2, NH3 and water vapour at 800°C. Answer : (c)

Mesozoic is the second-to-last era of Earth's geological history, lasting about 252 to 66 million years ago. Mesozoic is also called the Age of Reptiles. Answer : (c)

The evolutionary lineage of the horse is among the best-documented in all paleontology the horse family remains the classic example of evolution. As more and more horse fossils have been found, some ideas about horse evolution have changed, but the horse family remains a good example of evolution Answer : (c)

It is the formation of species without geographical isolation and these species are called sympatric speciation. It is reproductive, behavioural and temporal isolation. Answer : (d)

New genes/alleles are added to the new population and these are lost from the old population. There would be a gene flow if this gene migration, happens multiple times. If the same change occurs by chance, it is called genetic drift. Genetic drift is most important in small populations. Answer : (b)

All the varieties of Darwin's finches, evolved on the island itself. From the original seed-eating features, many other forms with altered beaks arose, enabling them to become insectivorous and vegetarian finches. This process of evolution of different species in a given geographical area starting from a point and literally radiating to other areas of geography (habitats) is called adaptive radiation. Answer : (c)

Typically, genetic drift occurs in small populations, where infrequently occurring alleles face a greater chance of being lost. Answer : (a)

1. Hugo de Vries gave mutation theory. 2. Charles Darwin: Origin of species 3. "Philosophie Zoologique" is a 1809 book by Jean-Baptiste Lamarck. 4. The biogenetic law is a theory of development and evolution proposed by Ernst Haeckel in Germany in the 1860s. 5. Weismann proposed the theory of the continuity of germ-plasm, a theory of heredity. Answer : (a)

Sweet potato (root modification) and potato (stem modification) is another example for analogy. Answer : (b)

Geographic isolation is a common way for the process of speciation to begin. Answer : (a)

The theory of natural selection dwells on natural selection acting on favorable variations. In simple words, we can explain this by saying the survival of the fittest. Answer : (b)

They perform similar functions i.e. swimming. Hence, analogous structures are a result of convergent evolution - different structures evolving for the same function and hence having similarity. Answer : (d)

In 1828, while working at the University of Königsberg in Königsberg, Germany, Karl Ernst von Baer proposed four laws of animal development, which came to be called von Baer's laws of embryology. Answer : (a)

Oparin of Russia and Haldane of England proposed that the first form of life could have come from pre-existing non-living organic molecules (e.g. RNA, protein, etc.) and that formation of life was preceded by chemical evolution, i.e., formation of diverse organic molecules from inorganic constituents. The conditions on earth were – high temperature, volcanic storms, reducing atmosphere containing CH4, NH3, etc. Answer : (b)