26. The distance between bacterial genes as determined from interrupted mating experiments are measured in units of
(1) cM                (2) minutes
(3) bp                (4) micrometers

The distance between bacterial genes as determined from interrupted mating experiments is measured in units of minutes.

Explanation of options:
(1) cM (centiMorgan) is a unit used in genetic mapping of eukaryotic chromosomes based on recombination frequency, not bacterial gene mapping.
(2) Minutes is the correct unit in bacterial interrupted mating experiments because the gene distance is measured by the time taken for gene transfer during conjugation.
(3) bp (base pairs) is a physical length unit of DNA but not used in interrupted mating to measure gene distance.
(4) Micrometers is a unit of physical length and not relevant for genetic distance measurement in this context.

In interrupted mating experiments, bacterial conjugation is stopped at different time intervals to observe the order and time at which donor genes enter the recipient cell. The time taken for a gene to transfer is proportional to its distance from the origin of transfer on the bacterial chromosome. This time unit (minutes) is thus the map unit for the bacterial chromosome, typically spanning about 100 minutes, indicating the relative position of genes.​​

Introduction:
Bacterial genetics uses interrupted mating experiments to map genes on the chromosome by measuring the time taken during conjugation for genes to transfer between cells. Unlike eukaryotic genetic maps that use centiMorgans, bacterial gene distance measurement relies on minutes to indicate gene location relative to the origin of transfer. This time-based mapping provides a clear understanding of bacterial chromosome structure and gene order.

This approach is crucial for studying bacterial gene linkage, ordering, and genetic recombination, enabling scientists to construct accurate genetic maps and facilitating deeper insights into bacterial genetics and molecular biology. The use of minutes as a unit reflects the direct relationship between transfer time and gene position on the circular bacterial chromosome.​​

Thus, the correct answer is (2) minutes.