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What does the one-gene, one-enzyme hypothesis state?
a. Genes are composed of stretches of DNA.
b. Genes are made of protein.
c. Genes code for ribozymes.
d. A single gene codes for a single protein.
Introduction:
Gene expression is a process by which the genetic information from the DNA (deoxyribonucleic acid) is copied to RNA (ribonucleic acid), that functions to translate it into proteins by the process of translation. Proteins are coded by genes present on the chromosomes. Enzymes are proteins having complex structures. Their enzymatic activity is determined by their complex globular structures. They function to accelerate the speed of any chemical reaction. They act on a substrate and converts it into product. They are not used up in the reaction they catalyze, but they can be recycled in the process so that they can catalyze a new round of reaction.
Answer to Problem 1TYK
Correct answer:
The hypothesis of one-gene one-enzyme states that a single protein is encoded by a single gene.
Explanation of Solution
Justification/ Explanation for the correct answer:
Option (d) is given that a single gene is meant for coding a single protein. One gene one enzyme hypothesis was given in 1941 by Edward Tatum and George wells beadle. The theory says that one gene is responsible for the expression of one enzyme that catalyzes a single step of a metabolic pathway. Hence, option (d) is correct.
Explanation for the incorrect answers:
Option (a) is given that the hypothesis one gene one enzyme states that genes are made of stretches of DNA. However, this is not so, as the hypothesis says that one gene is responsible for the coding and expression of one protein or enzyme. So, it is an incorrect option.
Option (b) is given that one-gene one-enzyme tells that proteins forms the genes. This is not the meaning of the hypothesis given because these are the genes which are present as information in the DNA and are first transcribed into RNA and then translated into proteins. So, it is an incorrect option.
Option (c) is given that one-gene one-enzyme hypothesis states that the ribozymes are encoded by the genes. Ribozymes are the enzymes that catalyzes particular type of chemical reactions. They are not the proteins but they are the RNA molecules. So, it is an incorrect option.
Hence, options (a), (b), and (c) are incorrect.
Therefore, it can be concluded that the hypothesis one-gene one-enzyme states that a single protein is encoded by a single gene and that single protein will take part in one reaction of the metabolic pathway.
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Chapter 16 Solutions
Biological Science
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