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Introduction:
The genes that are involved in the regulation of the lactose
Answer to Problem 1TYK
Correct answer:
Genes involved in the metabolism of the lactose are considered to be an operon because they are controlled by the same promoter. The operon is the gene segment, which is controlled by the same promoter.
Explanation of Solution
Explanation/Justification for the correct answer:
Option (d) gives that the genes are all controlled by the same promoter. The entire structural genes that encode enzymes required to use lactose as an energy source lie adjacent to each other in the lactose (or lac) operon under the control of a single lac promoter. Hence, Option (d) is correct.
Explanation for incorrect answers:
Option (a) gives that the genes occupy adjacent locations on the E. coli chromosome. The gene sequence, which regulates the metabolism of the lactose, is not located adjacently; they are located on the same DNA (deoxyribonucleic acid) sequence. So, it is an incorrect option.
Option (b) gives that the genes have a similar function. The genes that are involved in the metabolism of the lactose have different functions. They are involved in the secretion of different enzymes. So, it is an incorrect option.
Option (c) gives that the genes are all required for normal cell functioning. These genes are not required for the normal metabolism of the lactose in the cell. The operons are only responsible for the regulation of the genes. So, it is an incorrect option.
Hence, options (a), (b), and (c) are incorrect.
All the genes involved in the metabolism of the lactose are controlled by the same promoter and are called operon.
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Biology (MindTap Course List)BiologyISBN:9781337392938Author:Eldra Solomon, Charles Martin, Diana W. Martin, Linda R. BergPublisher:Cengage Learning