50 questions · timed · auto-graded
Similarity in structural design indicates towards a common ancestry.
Igneous rocks are formed from lava and hence no fossil can be found in them. Metamorphic rocks can be made from igneous or sedimentary rocks. Hence, ‘a’ is the correct answer.
Explanation:
Cretaceous period was the last and the longest segment of the mesozoic era. It lasted approx. 79 million years ago. During this time, reptiles were large in number and were dominant.
Explanation:
The animals or plants that evolve same structure along different directions due to adaptations to different needs is known as divergent or homologous evolution and it shows common ancestry. The thorn and tendrils of Bougainvillea and Cucurbita represent homology.
Explanation:
Precambrian is one of the four eras in earth's geological history.
Precambrian actually meant period before the Cambrian period of the Palaeozoic era.
Precambrian is divided into three periods- Azoic (no life), Archaeozoic (invisible life) and Proterozoic (age of early life).
It is believed that life appeared in Archeozoic period of Precambrian era.
Explanation:
An eon is the largest timespan in the geological timeline. An eon is subdivided into eras.
The Azoic Era was the oldest and long-lasting stage in the development of earth. There was no evidence of life in this era.
The Azoic era is the era when origin of the continental shelf occurred.
The continental shelf (Pangaea) was formed by the silica rich granite rocks of less density.
Explanation:
The conditions to maintain the Hardy-Weinberg equilibrium are no mutation, no gene flow, large population size, random mating, and no natural selection.
The Hardy-Weinberg equilibrium can be disrupted by deviations from any of its five main underlying conditions.
Hence, Under which condition, Hardy Weinberg's law is violated Natural selection, Mutation and Immigration and genetic drift.
So, the correct answer is 'All of the above'.
Explanation:
Homo erectus was a erect man from middle Pleistocene epoch. It lived from 1.7 to 0.25 million years ago. One of the important species of Homo erectus was the Peking man or Homo erectus pekinensis also called as Homo erectus sinanthropus or Sinanthropus pekinensis.
Explanation:
The structures which are similar in their morphology, anatomy, genetics and embryology but dissimilar in their function are called as homologous organs. Many mammals have similar limb structures. The flipper of a whale, the wing of a bat, and the leg of a cat are all very similar to the human arm.
Divergent evolution is the accumulation of differences between groups, which can lead to the formation of new species, usually a result of diffusion of the same species to different and isolated environments, which blocks the gene flow among the distinct populations allowing differentiated fixation of characteristics through genetic drift and natural selection.
Explanation:
When two animals/plants belonging to two distinct lineages of evolution, exhibit similarities with respect to adaptation to a certain environmental condition is called convergent evolution.
Example, wings of birds and insects, they have different structures internally but perform the same function, that is adaptation to aerial habitat.
Explanation:
In the early decades of the twentieth century, J.B.S. Haldane and Alexander Oparin independently set forth similar ideas concerning the conditions required for the origin of life on Earth. Both suggested that organic molecules could be formed from non organic materials in presence of an external energy source and that the primitive atmosphere was reducing and contained Ammonia and water vapour, among other gases.
Oparin suggested that organic compounds could have undergone a series of reactions leading to more complex molecules. He proposed that the molecules formed colloid aggregate or coacervates, in an aqueous environment. Haldane hypothesized that the oceans served as a huge cooking pot, powered by the sun or lighting, chemical reactions could occur in an aqueous environment to form a huge diversity of organic compounds.
Haldane coined the term 'prebiotic soup' that consisted of an abundance of methane, ammonia and water. The first organic molecules thought to have formed was Hydrocarbon chains, which were composed solely of hydrogen atoms bonded to carbon atoms. Hydrocarbons provided the foundation framework for the formation of more complex organic molecules, such as simple amino acids.
Lichens do not possess roots and hence air is their primary source for most elements. They will not grow in the areas that are polluted. So, lichen is used as a reliable indicator of atmospheric pollution.
Industrial melanism is not a mean character but is acquired by most of the individuals. Hence, it is an example of directional change.
Animal husbandry and plant breeding programmes need human intervention and desirable characters are introduced in plants and animals through manipulation. Hence, these are examples of artificial selection.
Explanation:
During human evolution, several species and subspecies roamed on earth and lived together and also possibly exchanged genes, thus, obscuring the exact lineage which ultimately evolved into modern humans, but Homo erectus that lived around middle Pleistocene, are thought of as the direct line that evolved into modern man. The most important subspecies of Homo erectus are Java man, Peking man and Heidelberg man.