Who introduced the idea of a spontaneous generation ?
The doctrine of spontaneous generation was coherently synthesized by Aristotle, who compiled and expanded the work of earlier natural philosophers and the various ancient explanations for the appearance of organisms, and was taken as scientific fact for two millennia.
Spontaneous generation of bacteria from decomposing broth was disproved in 1860 by :
The principle of sterilization is based upon experiments carried by :
Sterilization is the killing or removal of all microorganisms, including bacterial spores, which are highly resistant.It was carried by L.Pasteur.
Life was created by some supernatural power. This theory is :
In creationism, special creation is a theological doctrine which states that the universe and all life in it originated in its present form by unconditional fiat or divine decree.
About how long ago was the earth formed ?
Earth was formed about 4.6 billion years ago.
Modern theory of origin of life was propounded by :
Modern Theory or Oparin-Haldane Theory of Origin of Life:
According to this theory life originated on early earth through physico-chemical processes of atoms combining to form molecules, molecules in turn reacting to produce inorganic and organic compounds. Organic compounds interacted to produce all types of macromolecules which organised to form the first living system or cells.
Which of the following gas was absent on primitive earth :
The primitive atmosphere of the earth was devoid of oxygen. Components of prebiotic atmosphere were water vapour, methane, CO, hydrogen, nitrogen, ammonia, etc. As the earth cooled down, water wapor condensed to form oceans.
Which English scientist worked on origin of life and finally settled in India :
John Burdon Sanderson Haldane FRS, nicknamed "Jack" or "JBS", was a British-Indian scientist known for his work in the study of physiology, genetics, evolutionary biology, and mathematics.He worked on the origin of life.
Nucleoprotoeins most probably gave the first sign of :
The giant nucleoprotein molecules were formed by the union of nucleic acid and protein molecules. These nucleoprotein particles were described as free living genes. Nucleoproteins gave most probably the first sign of life.
Life originated :
There is no life in moon due to the absence of :
Moon is a natural satellite of earth but life on the moon is not possible as on the earth because of many reasons. Firstly, there is no water on the moon, which is the first and foremost requirement for the life. Life first started on the earth because of water and if no water we can imagine no life.
Homologous organ are :
Homology refers to similar structures with dissimilar functions, but with similar origin and architecture.
Example of homologous organs are :
Which of the following are homologous structures :
Nails of humans and claws of cat: These are homologous organs as they have similar structure but perform different function.
Evolution of diversified species due to environmental changes is called :
Divergent evolution is the process whereby groups from the same common ancestor evolve and accumulate differences, resulting in the formation of new species.
Divergent evolution may occur as a response to changes in abiotic factors, such as a change in environmental conditions, or when a new niche becomes available. Alternatively, divergent evolution may take place in response to changes in biotic factors, such as increased or decreased pressure from competition or predation.
Wings of birds and butterflies are :
Wings of butterfly and wings of a bird , they both are analogus organs . Wings of butterfly does not have hollow bones wheres birds have hollow bones attached to its feathers and they are used from protecting it from cold also.
Which of the following is a vestigial structure in man ?
Which of the following is not a vestigial organ in man :
Peripatus is a connecting link between :
Peripatus is a primitive arthropod having joined paired legs, compound eyes and tracheas like other arthropods but also displays certain annelidan characteristics, such as worm-like segmented body, non-chitinous cuticle and segmental nephridia.It forms a connecting link between Annelida and Arthropoda.
A connecting link between Protozoa and Porifera is :
Proterospongia is considered as a connecting link between protozoa and the porifera because it has both protozoan and poriferan characters like it is a colonial protozoan and its cells are similar to collar cells of sponges.
Which one represents a connecting link as an evidence from comparative anatomy in favour of organic evolution ?
Fossil remains of Archaeopteryx indicate that :
"Ontogeny repeats phylogeny" was coined by :
"Ontogeny recapitulates phylogeny" is a catchy phrase coined by Ernst Haeckel, a 19th century German biologist and philosopher to mean that the development of an organism (ontogeny) expresses all the intermediate forms of its ancestors throughout evolution (phylogeny). His theory was later proved wrong, but the catch phrase remains.
Study of human evolution is under :
The study of human evolution involves several scientific disciplines, including physical anthropology, primatology, archaeology, paleontology, neurobiology, ethology, linguistics, evolutionarypsychology, embryology and genetics.
Evolution of man is believed to have taken place in :
Humans first evolved in Africa, and much of human evolution occurred on that continent. The fossils of early humans who lived between 6 and 2 million years ago come entirely from Africa.
The main advantage of bipedal locomotion is :
The clear advantage of bipedalism was the possibility for ancient hominin species to use their hands. With the evolution of bipedalism, this special advantage was evolved only by the primates. This advantage offered a benefit that overcame the fatal disadvantage of slow speed.