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Jurassic period of the Mesozoic era characterized by?
Jurassic period of Mesozoic era characterized presence of Gymnosperms as dominant plant and first birds evolved from reptiles. Dianasours are also a kind of reptiles.
Organic compounds first evolved in earth required for origin of life were_____.
The organic compounds first evolved in earth required for origin of life were proteins and nucleic acids. Proteins are made of amino acids arranged in different order and DNA and RNA are nucleic acids.
Adaptive radiation does not confirm _______
Which of the following bird will be called most successfully evolved?
An organism that lays 5 eggs, hatch the 5 eggs to reproduce 5 offspring can be considered as most evolved out of the other given condition. Least evolved organism lays more egg but produce only a few offspring.
By studying analogous structures we look for ______.
Analogous organs are those organs which have the same function but are quite different in their fundamental structure and embryonic origin. For example, the wing of an insect and the wing of a bird are analogous organs. Both these organs are used for flying in the air but they re very different in structure. An insect wing is an extension of the integument whereas a bird wing is formed of limb bones covered with flesh, skin, and feathers. Each has evolved from a separate ancestral population as a means of a more efficient mode of locomotion. Similarity developed in distantly related groups as an adaptation for the same function is called analogy or convergent evolution.
Thus, the correct answer is option B.
Which one of the following is incorrect about the characteristics of protobionts (coacervates and microspheres) as envisaged in the abiogenic origin of life?
The correct option is Option B.
A protobiont is an aggregate of abiotically produced organic molecules surrounded by a membrane or a membrane-like structure. Protobionts exhibit some of the properties associated with life, including simple reproduction, metabolism and excitability, as well as the maintenance of an internal chemical environment different from that of their surroundings. It has been suggested that they are a key step in the origin of life on earth. Experiments by Sidney W. Fox and Aleksandr Oparin have demonstrated that they may be formed spontaneously, in conditions similar to the environment thought to exist on an early Earth.
Protobionts are excitable, metabolically active, inaccurately reproducing protein clusters. These clusters form when their protein parts are mixed with cold water: they self-assemble into microspheres. Protobionts also can release voltage like a neuron because some protobionts store energy through a similar method of membrane potential as organelles. If coated with a semipermeable membrane, a protobiont will swell and contract osmotically when in solutions of differing salt concentrations. The protobiont shares its weak catabolic capabilities with the liposome. They were partially isolated from the environment, but they could not separate combinations of molecules from the surroundings. Other statements are correct and only option B is incorrect.
An important evidence in favour of organic evolution is the occurrence of
There are many evidences that favor the organic evolution of life. According to this concept life originate from pre-existing organisms by evolution in cousr of time. Homologous and vestigial organs hit the uses of different organs in different organism for different purpose.
Assertion: The earliest organisms that appeared on the earth were non-green and presumably anaerobes.
Reason: The first autotrophic organisms were the chemo-autotrophs that never released oxygen.
The earliest organisms that appeared on the earth were non-green and presumably anaerobes. The first autotrophic organisms were the chemo-autotrophs that never released oxygen. Both the statements are correct but reason does not explain the assertion.
According to Neo-Darwinism, natural selection operates through_______.
According to Neo-Darwinism, natural selection operates through differential reproduction. During sexual reproduction gametes are formed by meiosis division in which crossing over brings about change in traits that leads to variation for natural selection.
Vermiform appendix in man, nictitating membrane and wisdom teeth are ______.
Vermiform appendix in man, nictitating membrane and wisdom teeth are vestigial organs of human beings. These organs are functional in our ancestors but in present human beings they have become functionless and only present as remain.
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