What is meant by selective breeding

Selective  breeding also artifical selection . Selective breeding is the process is used by humans beings to produce new organisms with desirable characteristics.

Example: The cattles produces a huge amount of milk. It mens that the meat we eat is the selective breeding of  ships ,chikens, pig and dogs etc.

a catalyst

Explanation:

Catalyst is a substance that influences the rate of reaction without being consumed in the reaction. They increase the rate of reaction by decreasing the activation energy of the reaction. In biological system, enzymes are referred to as biological catalyst or biocatalyst. They are generally protein in nature and are very specific for their substrate. They also increases the rate of biological reaction by forming enzyme-substrate complex.

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