Q3 of 16 Page 136

Match the following :

1. Lamarck- (d) theory of inheritance of acquired characters


Explanation- Lamarck had given the theory of inheritance of acquired characters. According to him depending on the use and misuse of the organ, new needs changes in the traits of the organism takes place. The organism acquires these traits according to the organ he is using most or using least. He thought these acquired traits are transferred to the next generation and depending on these concepts he had given the theory of inheritance of acquired characters.


2. Darwin- (c) Theory of natural selection


Explanation- Darwin had given the theory of natural selection. According to him nature selects and favors the survival of those organisms which have advantageous variations which help the organism to get adapt in the changing environment and these advantageous variations are selected and are inherited by the next generation. Those variations which do not provide any survival advantage are not selected by nature.


3. Hugo De Vries- (b) Mutation theory


Explanation-Hugo De Vries was the one who had given the concept of mutation. He suggested that there are variations (changes in the genetic makeup of an organism) which are caused due to sudden changes in the genetic makeup. He termed the variations caused by sudden changes in genetic makeup as Mutation.


4. Oparin- (e) Theory of chemical evolution


Explanation- This theory was an answer to the question that how life originated on the earth and was given by both Oparin and Haldane independently. According to his theory initially on earth, there was no oxygen and life had arisen due to various chemical changes over here. He suggested that solar radiations, ultraviolet lights, and lightning had caused these chemical reactions due to which life was aroused.


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